Science.gov

Sample records for 1-2 ghz band

  1. Inter-spin distance determination using L-band (1-2 GHz) non-adiabatic rapid sweep electron paramagnetic resonance (NARS EPR)

    PubMed Central

    Kittell, Aaron W.; Hustedt, Eric J.; Hyde, James S.

    2014-01-01

    Site-directed spin-labeling electron paramagnetic resonance (SDSL EPR) provides insight into the local structure and motion of a spin probe strategically attached to a molecule. When a second spin is introduced to the system, macromolecular information can be obtained through measurement of inter-spin distances either by continuous wave (CW) or pulsed electron double resonance (ELDOR) techniques. If both methodologies are considered, inter-spin distances of 8 to 80 Å can be experimentally determined. However, there exists a region at the upper limit of the conventional X-band (9.5 GHz) CW technique and the lower limit of the four-pulse double electron-electron resonance (DEER) experiment where neither method is particularly reliable. The work presented here utilizes L-band (1.9 GHz) in combination with non-adiabatic rapid sweep (NARS) EPR to address this opportunity by increasing the upper limit of the CW technique. Because L-band linewidths are three to seven times narrower than those at X-band, dipolar broadenings that are small relative to the X-band inhomogeneous linewidth become observable, but the signal loss due to the frequency dependence of the Boltzmann factor, has made L-band especially challenging. NARS has been shown to increase sensitivity by a factor of five, and overcomes much of this loss, making L-band distance determination more feasible [1]. Two different systems are presented and distances of 18–30 Å have been experimentally determined at physiologically relevant temperatures. Measurements are in excellent agreement with a helical model and values determined by DEER. PMID:22750251

  2. A cooled 1-2 GHz balanced HEMT amplifier

    NASA Astrophysics Data System (ADS)

    Padin, Stephen; Ortiz, Gerardo G.

    1991-07-01

    The design details and measurement results for a cooled 1-GHz-bandwidth L-band HEMT amplifier are presented. The HEMT noise parameters were measured at a physical temperature of 12 K, and a balanced configuration was adopted. This has the advantage of providing a good input match even though the amplifiers in the two arms of the balanced circuit are poorly matched. However, there are disadvantages. The loss of the input hybrid degrades the noise temperature and coupling errors in the hybrids, and differences between the amplifiers reduce the gain and result in a noise contribution from the input load. In the amplifier described, these effects degrade the noise temperature by less than 1 K. The amplifier uses commercially available packaged HEMT devices. At a physical temperature of 12 K the amplifier achieves noise temperatures between 3 and 6 K over the 1-2-GHz band. The associated gain is about 20 dB.

  3. 14/12-GHz-band satellite communication services

    NASA Astrophysics Data System (ADS)

    Hayashi, Kunihiro; Nagaki, Kiyoaki; Mori, Yasuo

    1990-01-01

    Three new systems for integrated TV-relay services have been developed: Satellite Video Comunication Service (SVCS) and Satellite Digital Communication Service (SDCS), with Japan's 14/12-GHz-band commercial communication satellites. These systems have been in commercial use since May 1989. Usually SVCS and SDCS have been provided using Ka-band (30/20 GHz-band) of CS-2 and Cs-3. This paper provides an overview of the design, the performance, and the systems of the new 14/12-GHz-band satellite communication services.

  4. Ka-band (32 GHz) allocations for deep space

    NASA Technical Reports Server (NTRS)

    Degroot, N. F.

    1987-01-01

    At the 1979 World Administrative Conference, two new bands were allocated for deep space telecommunications: 31.8 to 32.3 GHz, space-to-Earth, and 34.2 to 34.7 GHz, Earth-to-space. These bands provide opportunity for further development of the Deep Space Network and its support of deep space research. The history of the process by which JPL/NASA developed the rationale, technical background, and statement of requirement for the bands are discussed. Based on this work, United States proposals to the conference included the bands, and subsequent U.S. and NASA participation in the conference led to successful allocations for deep space telecommunications in the 30 GHz region of the spectrum. A detailed description of the allocations is included.

  5. 77 FR 45558 - 4.9 GHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-01

    ... to the 5 GHz band widely used by unlicensed Wi-Fi networks. We seek comment on whether expanding... Rulemaking Proceedings, 63 FR 24121, May 1 (1998). Electronic Filers: Comments may be filed electronically... broadband network, technical rule changes, aeronautical mobile operations, interoperability standards,...

  6. 77 FR 45503 - 4.9 GHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-01

    ...-4990 MHz (4.9 GHz) band applicants from certified frequency coordination. Next, the Commission corrects.... Finally, the Commission corrects minor errors in the Public Safety Pool Frequency Table and associated... print, audio cassette, and Braille) are available to persons with disabilities or by sending an email...

  7. Ka-band (32 GHz) benefits to planned missions

    NASA Technical Reports Server (NTRS)

    Hansen, D. M.; Kliore, A. J.

    1987-01-01

    The benefits of using 32 GHz downlinks for a set of deep space missions, as well as the implications to radio science and the Deep Space Network (DSN) are documented. The basic comparison is between the use of the current X-band (8.4 GHz) and a 32 GHZ (Ka-band) downlink. There was shown to be approximately an 8 dB (about 600%) link advantage for 32 GHz. This 8 dB advantage would be able to either reduce mission cost or improve mission science return. Included here are studies on how the 8 dB advantage would be used for the Cassini and Mars Sample Return missions. While the work is preliminary, it shows that the 8 dB advantage can be exploited to provide large benefits to future deep space missions. There can be significant mass and/or power savings to the spacecraft, which can translate into cost savings. Alternatively, the increased downlink telecommunications performance can provide a greater science return.

  8. 30/20 GHz and 6/4 GHz band transponder development for communications satellite CS-3

    NASA Astrophysics Data System (ADS)

    Tanaka, Masayoshi; Nakamura, Makoto; Okamoto, Teruki; Kumazawa, Hiroyuki

    The next phase communications satellite CS-3 will be launched in 1988 as a successor to CS-2. The CS-3 is composed of two 6/4 GHz band and ten 30/20 GHz band transponders and its mission life is seven years. This paper describes the newly developed CS-3 transponder, especially a 4 GHz band 7 watt GaAs FET amplifier, Ka-band frequency single-conversion, a 30 GHz band low noise amplifier, and a 20 GHz band 10 watt TWTA. The introduction of these new technologies contributes significantly to reducing the CS-3 transponder weight and size, and to improving performance characteristics and insuring a long life.

  9. 47 CFR 101.97 - Future licensing in the 18.30-19.30 GHz band.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Future licensing in the 18.30-19.30 GHz band. 101.97 Section 101.97 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Relocation from the 18.58-19.30 Ghz Band § 101.97 Future licensing in the 18.30-19.30 GHz band. (a) All...

  10. 47 CFR 101.97 - Future licensing in the 18.30-19.30 GHz band.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Future licensing in the 18.30-19.30 GHz band. 101.97 Section 101.97 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Relocation from the 18.58-19.30 Ghz Band § 101.97 Future licensing in the 18.30-19.30 GHz band. (a) All...

  11. 47 CFR 101.97 - Future licensing in the 18.30-19.30 GHz band.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Future licensing in the 18.30-19.30 GHz band. 101.97 Section 101.97 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Relocation from the 18.58-19.30 Ghz Band § 101.97 Future licensing in the 18.30-19.30 GHz band. (a) All...

  12. 47 CFR 101.97 - Future licensing in the 18.30-19.30 GHz band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Future licensing in the 18.30-19.30 GHz band. 101.97 Section 101.97 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Relocation from the 18.58-19.30 Ghz Band § 101.97 Future licensing in the 18.30-19.30 GHz band. (a) All...

  13. A 250 GHz Photonic Band Gap Gyrotron Amplifier

    NASA Astrophysics Data System (ADS)

    Nanni, Emilio A.; Lewis, Samantha M.; Shapiro, Michael A.; Temkin, Richard J.

    2012-10-01

    Initial results for a high power 250 GHz gyrotron traveling wave tube (gyro-TWT) amplifier will be presented. The amplifier uses a novel photonic band gap (PBG) interaction circuit that confines the TE03-like mode for operation. Stability from oscillations in lower order modes is provided by the PBG circuit. At 26.6 kV and 0.25 A the gyro-TWT operates with peak small signal gain of 27.3 dB at 251 GHz. The instantaneous -3 dB bandwidth of the amplifier at peak gain is 0.4 GHz. The amplifier can be tuned for operation from 245-254 GHz. A peak output power of 7.5 W has been measured. Experimental results taken over a wide range of parameters, 15-30 kV and 0.25-0.5 A, show good agreement with a theoretical model in the small signal gain regime. The theoretical model incorporates cold test measurements for the transmission line, input coupler, PBG waveguide and mode converter.

  14. Radar response to vegetation. II - 8-18 GHz band

    NASA Technical Reports Server (NTRS)

    Ulaby, F. T.; Bush, T. F.; Batlivala, P. P.

    1975-01-01

    The results of experimental studies on the backscattering properties of corn, milo, soybeans, and alfalfa are presented. The measurements were made during the summer of 1973 over the 8-18 GHz frequency band. The data indicate that soil moisture estimation is best accomplished at incidence angles near nadir with lower frequencies while crop discrimination is best accomplished using two frequencies at incidence angles ranging from 30 deg to 65 deg. It is also shown that temporal plant morphology variations can cause extreme variations in the values of the scattering coefficients. These morphological changes can be caused by growth, heavy rain, and in the case of alfalfa, harvesting.

  15. 47 CFR 25.264 - Requirements to facilitate reverse-band operation in the 17.3-17.8 GHz band of 17/24 GHz...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Requirements to facilitate reverse-band operation in the 17.3-17.8 GHz band of 17/24 GHz Broadcasting-satellite Service and Direct Broadcast Satellite Service space stations. 25.264 Section 25.264 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES...

  16. 47 CFR 15.251 - Operation within the bands 2.9-3.26 GHz, 3.267-3.332 GHz, 3.339-3.3458 GHz, and 3.358-3.6 GHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Operation within the bands 2.9-3.26 GHz, 3.267-3.332 GHz, 3.339-3.3458 GHz, and 3.358-3.6 GHz. 15.251 Section 15.251 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission...

  17. 47 CFR 15.251 - Operation within the bands 2.9-3.26 GHz, 3.267-3.332 GHz, 3.339-3.3458 GHz, and 3.358-3.6 GHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Operation within the bands 2.9-3.26 GHz, 3.267-3.332 GHz, 3.339-3.3458 GHz, and 3.358-3.6 GHz. 15.251 Section 15.251 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission...

  18. 47 CFR 15.251 - Operation within the bands 2.9-3.26 GHz, 3.267-3.332 GHz, 3.339-3.3458 GHz, and 3.358-3.6 GHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Operation within the bands 2.9-3.26 GHz, 3.267-3.332 GHz, 3.339-3.3458 GHz, and 3.358-3.6 GHz. 15.251 Section 15.251 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission...

  19. 47 CFR 15.251 - Operation within the bands 2.9-3.26 GHz, 3.267-3.332 GHz, 3.339-3.3458 GHz, and 3.358-3.6 GHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Operation within the bands 2.9-3.26 GHz, 3.267-3.332 GHz, 3.339-3.3458 GHz, and 3.358-3.6 GHz. 15.251 Section 15.251 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission...

  20. 47 CFR 15.251 - Operation within the bands 2.9-3.26 GHz, 3.267-3.332 GHz, 3.339-3.3458 GHz, and 3.358-3.6 GHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Operation within the bands 2.9-3.26 GHz, 3.267-3.332 GHz, 3.339-3.3458 GHz, and 3.358-3.6 GHz. 15.251 Section 15.251 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission...

  1. 47 CFR 101.97 - Future licensing in the 18.30-19.30 GHz band.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Future licensing in the 18.30-19.30 GHz band... Relocation from the 18.58-19.30 Ghz Band § 101.97 Future licensing in the 18.30-19.30 GHz band. (a) All major....58-19.30 band after June 8, 2000 (with the exception of certain low power operations authorized...

  2. Amplifier Module for 260-GHz Band Using Quartz Waveguide Transitions

    NASA Technical Reports Server (NTRS)

    Padmanabhan, Sharmila; Fung, King Man; Kangaslahti, Pekka P.; Peralta, Alejandro; Soria, Mary M.; Pukala, David M.; Sin, Seth; Samoska, Lorene A.; Sarkozy, Stephen; Lai, Richard

    2012-01-01

    Packaging of MMIC LNA (monolithic microwave integrated circuit low-noise amplifier) chips at frequencies over 200 GHz has always been problematic due to the high loss in the transition between the MMIC chip and the waveguide medium in which the chip will typically be used. In addition, above 200 GHz, wire-bond inductance between the LNA and the waveguide can severely limit the RF matching and bandwidth of the final waveguide amplifier module. This work resulted in the development of a low-loss quartz waveguide transition that includes a capacitive transmission line between the MMIC and the waveguide probe element. This capacitive transmission line tunes out the wirebond inductance (where the wire-bond is required to bond between the MMIC and the probe element). This inductance can severely limit the RF matching and bandwidth of the final waveguide amplifier module. The amplifier module consists of a quartz E-plane waveguide probe transition, a short capacitive tuning element, a short wire-bond to the MMIC, and the MMIC LNA. The output structure is similar, with a short wire-bond at the output of the MMIC, a quartz E-plane waveguide probe transition, and the output waveguide. The quartz probe element is made of 3-mil quartz, which is the thinnest commercially available material. The waveguide band used is WR4, from 170 to 260 GHz. This new transition and block design is an improvement over prior art because it provides for better RF matching, and will likely yield lower loss and better noise figure. The development of high-performance, low-noise amplifiers in the 180-to- 700-GHz range has applications for future earth science and planetary instruments with low power and volume, and astrophysics array instruments for molecular spectroscopy. This frequency band, while suitable for homeland security and commercial applications (such as millimeter-wave imaging, hidden weapons detection, crowd scanning, airport security, and communications), also has applications to

  3. A 3.16-7 GHz transformer-based dual-band CMOS VCO

    NASA Astrophysics Data System (ADS)

    Zhu, Li; Zhigong, Wang; Zhiqun, Li; Qin, Li; Faen, Liu

    2015-03-01

    A dual-band, wide tuning range voltage-controlled oscillator that uses transformer-based fourth-order (LC) resonator with a compact common-centric layout is presented. Compared with the traditional wide band (VCO), it can double frequency tuning range without degrading phase noise performance. The relationship between the coupling coefficient of the transformer, selection of frequency bands, and the quality factor at each band is investigated. The transformer used in the resonator is a circular asymmetric concentric topology. Compared with conventional octagon spirals, the proposed circular asymmetric concentric transformer results in a higher quality-factor, and hence a lower oscillator phase noise. The VCO is designed and fabricated in a 0.18-μm CMOS technology and has 75% wide tuning range of 3.16-7.01 GHz. Depending on the oscillation frequency, the VCO current consumption is adjusted from 4.9 to 6.3 mA. The measured phase noises at 1 MHz offset from carrier frequencies of 3.1, 4.5, 5.1, and 6.6 GHz are -122.5, -113.3, -110.1, and -116.8 dBc/Hz, respectively. The chip area, including the pads, is 1.2 × 0.62 mm2 and the supply voltage is 1.8 V. Project supported by the National High Technology Research and Development Program of China (No. 2011AA10305) and the National Natural Science Foundation of China (No. 60901012).

  4. SINGLE LOOP - MULTI GAP RESONATOR FOR WHOLE BODY EPR IMAGING OF MICE AT 1.2 GHZ

    PubMed Central

    Petryakov, Sergey; Samouilov, Alexandre; Kesselring, Eric; Wasowicz, Tomasz; Caia, George L.; Zweier, Jay L.

    2009-01-01

    For whole body EPR imaging of small animals, typically low frequencies of 250–750 MHz have been used due to the microwave losses at higher frequencies and the challenges in designing suitable resonators to accommodate these large lossy samples. However, low microwave frequency limits the obtainable sensitivity. L-band frequencies can provide higher sensitivity, and have been commonly used for localized in vivo EPR spectroscopy. Therefore, it would be highly desirable to develop an L-band microwave resonator suitable for in vivo whole body EPR imaging of small animals such as living mice. A 1.2 GHz 16 gap resonator with inner diameter of 43 mm and 48 mm length was designed and constructed for whole body EPR imaging of small animals. The resonator has good field homogeneity and stability to animal induced motional noise. Resonator stability was achieved with electrical and mechanical design utilizing a fixed position double coupling loop of novel geometry, thus minimizing the number of moving parts. Using this resonator, high quality EPR images of lossy phantoms and living mice were obtained. This design provides good sensitivity, ease of sample access, excellent stability and uniform B1 field homogeneity for in vivo whole body EPR imaging of mice at 1.2 GHz. PMID:17625940

  5. A Ka-band (32 GHz) beacon link experiment (KABLE) with Mars Observer

    NASA Technical Reports Server (NTRS)

    Riley, A. L.; Hansen, D. M.; Mileant, A.; Hartop, R. W.

    1987-01-01

    A proposal for a Ka-Band (32 GHz) Link Experiment (KABLE) with the Mars Observer mission was submitted to NASA. The experiment will rely on the fourth harmonic of the spacecraft X-band transmitter to generate a 33.6 GHz signal. The experiment will rely also on the Deep Space Network (DSN) receiving station equipped to simultaneously receive X- and Ka-band signals. The experiment will accurately measure the spacecraft-to-Earth telecommunication link performance at Ka-band and X-band (8.4 GHz).

  6. 47 CFR 15.257 - Operation within the band 92-95 GHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Operation within the band 92-95 GHz. 15.257 Section 15.257 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.257 Operation within the band 92-95 GHz. (a) Operation of devices under...

  7. 47 CFR 15.255 - Operation within the band 57-64 GHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Operation within the band 57-64 GHz. 15.255 Section 15.255 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.255 Operation within the band 57-64 GHz. (a) Operation under the provisions...

  8. New space research frequency band proposals in the 20- to 40.5-GHz range

    NASA Technical Reports Server (NTRS)

    Bishop, D. F.

    1991-01-01

    Future space research communications systems may require spectra above 20 GHz. Frequency bands above 20 GHz are identified that are suitable for space research. The selection of the proper bands depends on consideration of interference with other radio services, adequate bandwidths, link performance, and technical requirements for practical implementation.

  9. 77 FR 48097 - Operation of Radar Systems in the 76-77 GHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-13

    ... modify the emission limits for vehicular radar systems operating within the 76-77 GHz band. Specifically.... 15.253 of the rules for vehicular radar systems operating in the 76-77 GHz band. Vehicular radars can... (NPRM), 77 FR 35176, June 16, 2011, in which it sought public comment on proposed amendments to Sec....

  10. 76 FR 35176 - Operation of Radar Systems in the 76-77 GHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-16

    ... emission limits be modified for vehicular radar systems operating within the 76- 77 GHz band. Specifically... proposes to modify its rules for vehicular radar systems operating in the 76-77 GHz band as TMC requests... there is very little likelihood that vehicular radar systems operating at either the current or...

  11. 47 CFR 101.537 - 24 GHz band subject to competitive bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false 24 GHz band subject to competitive bidding. 101.537 Section 101.537 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES 24 GHz Service and Digital Electronic Message Service §...

  12. 75 FR 17349 - Operations of Wireless Communications Services in the 2.3 GHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-06

    ... December 2007, the Commission released a Notice of Proposed Rulemaking, 73 FR 2437 (January 15, 2008) (NPRM... COMMISSION 47 CFR Part 27 Operations of Wireless Communications Services in the 2.3 GHz Band AGENCY: Federal...) seeks comment on revising the performance requirements for the 2.3 GHz Wireless Communications...

  13. 0.9 GHz and 2.4 GHz dual-band SiGe HBT LNA

    NASA Astrophysics Data System (ADS)

    Zhiyi, Lu; Hongyun, Xie; Wenjuan, Huo; Wanrong, Zhang

    2013-02-01

    This paper presents design and implementation of a dual-band LNA using a 0.35 μm SiGe HBT process for 0.9 GHz GSM and 2.4 GHz WLAN applications. PCB layout parasitic effects have a vital effect on circuit performance and are accounted for using electro-magnetic (EM) simulation. Design considerations of noise decoupling, input/output impedance matching, and current reuse are described in detail. At 0.9/2.4 GHz, gain and noise figure are 13/16 dB and 4.2/3.9 dB, respectively. Both S11 and S22 are below -10 dB. Power dissipation is 40 mW at 3.5 V supply.

  14. 78 FR 21320 - Unlicensed National Information Infrastructure (U-NII) Devices in the 5 GHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-10

    ...This document proposes to amend the Commission's rules governing the operation of Unlicensed National Information Infrastructure (U-NII) devices in the 5 GHz band. The Commission has gained much experience with U-NII devices since it first made spectrum available in the 5 GHz band for U-NII in 1997. The Commission believes that the time is now right to revisit the rules. The initiation of this......

  15. Wireless Channel Characterization in the 5 GHz Microwave Landing System Extension Band for Airport Surface Areas

    NASA Technical Reports Server (NTRS)

    Matolak, David W.

    2007-01-01

    In this project final report, entitled "Wireless Channel Characterization in the 5 GHz Microwave Landing System Extension Band for Airport Surface Areas," we provide a detailed description and model representation for the wireless channel in the airport surface environment in this band. In this executive summary, we review report contents, describe the achieved objectives and major findings, and highlight significant conclusions and recommendations.

  16. Design and realization of a planar ultrawideband antenna with notch band at 3.5 GHz.

    PubMed

    Azim, Rezaul; Islam, Mohammad Tariqul; Misran, Norbahiah; Yatim, Baharudin; Arshad, Haslina

    2014-01-01

    A small antenna with single notch band at 3.5 GHz is designed for ultrawideband (UWB) communication applications. The fabricated antenna comprises a radiating monopole element and a perfectly conducting ground plane with a wide slot. To achieve a notch band at 3.5 GHz, a parasitic element has been inserted in the same plane of the substrate along with the radiating patch. Experimental results shows that, by properly adjusting the position of the parasitic element, the designed antenna can achieve an ultrawide operating band of 3.04 to 11 GHz with a notched band operating at 3.31-3.84 GHz. Moreover, the proposed antenna achieved a good gain except at the notched band and exhibits symmetric radiation patterns throughout the operating band. The prototype of the proposed antenna possesses a very compact size and uses simple structures to attain the stop band characteristic with an aim to lessen the interference between UWB and worldwide interoperability for microwave access (WiMAX) band. PMID:25133245

  17. Design and Development of Thermistor based Power Meter at 140 GHz Frequency Band

    NASA Astrophysics Data System (ADS)

    Roy, Rajesh; Kush, Abhimanyue Kumar; Dixit, Rajendra Prasad

    2011-12-01

    Design and development of thermistor based power meter at 140 gigahertz (GHz) frequency band have been presented. Power meter comprises power sensor, amplifier circuit and dialog based graphical user interface in visual C++ for the average power measurement. The output power level of a component or system is very critical design factor. Thus there was a need of a power meter for the development of millimeter wave components at 140 GHz frequency band. Power sensor has been designed and developed using NTC (Negative Temperature Coefficient) thermistors. The design aims at developing a direct, simple and inexpensive power meter that can be used to measure absolute power at 140 GHz frequency band. Due to absorption of 140 GHz frequencies, resistance of thermistor changes to a new value. This change in resistance of thermistor can be converted to a dc voltage change and amplified voltage change can be fed to computer through data acquisition card. Dialog based graphical user interface (GUI) has been developed in visual C++ language for average power measurement in dBm. WR6 standard rectangular waveguide is the input port for the sensor of power meter. Temperature compensation has been achieved. Moderate sensor return loss greater than 20 dB has been found over the frequency range 110 to 170 GHz. The response time of the power sensor is 10 second. Average power accuracy is better than ±0.25 dB within the power range from -10 to 10 dBm at 140 GHz frequency band.

  18. The Celestial Reference Frame at X/Ka-band (8.4/32 GHz)

    NASA Technical Reports Server (NTRS)

    Jacobs, C. S.; Clark, J. E.; Heflin, M. B.; Skjerve, L. J.; Sovers, O. J.; Garcia-Miro, C.; Moll, V. E.; Horiuchi, S.

    2011-01-01

    A celestial reference frame at X/Ka-band (8.4/32 GHz) has been constructed using fifty-one 24-hour sessions with the Deep Space Network. We report on observations which have detected 436 sources covering the full 24 hours of right ascension and declinations down to -45 deg. Comparison of this X/Ka-band frame to the S/X-band (2.3/8.4 GHz) ICRF2 shows wRMS agreement of 200 micro-arcsec in a cos delta and 290 micro-arcsec in delta. There is evidence for zonal errors at the 100 micro-arcsec level. Known errors include limited SNR, lack of phase calibration, troposphere mismodelling, and limited southern geometry. The motivations for extending the ICRF to frequencies above 8 GHz are to access more compact source morphology for improved frame stability, to provide calibrators for phase referencing, and to support spacecraft navigation at Ka-band.

  19. Feasiblity study for a 34 GHz (Ka band) gyroamplifier

    NASA Technical Reports Server (NTRS)

    Stone, D. S.; Bier, R. E.; Caplan, M.; Huey, H. E.; Pirkle, D. R.; Robinson, J. D.; Thompson, L.

    1984-01-01

    The feasibility of using a gyroklystron power tube as the final amplifier in a 400 kW CW 34 GHz transmitter on the Goldstone Antenna is investigated. A conceptual design of the gyroklystron and the transmission line connecting it with the antenna feed horn is presented. The performance characteristics of the tube and transmission line are compared to the transmitter requirements for a deep space radar system. Areas of technical risk for a follow-on hardware development program for the gyroklystron amplifier and overmoded transmission line components are discussed.

  20. 47 CFR 15.256 - Operation of level probing radars within the bands 5.925-7.250 GHz, 24.05-29.00 GHz, and 75-85 GHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Operation of level probing radars within the bands 5.925-7.250 GHz, 24.05-29.00 GHz, and 75-85 GHz. 15.256 Section 15.256 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.256 Operation...

  1. On-wafer vector network analyzer measurements in the 220-325 Ghz frequency band

    NASA Technical Reports Server (NTRS)

    Fung, King Man Andy; Dawson, D.; Samoska, L.; Lee, K.; Oleson, C.; Boll, G.

    2006-01-01

    We report on a full two-port on-wafer vector network analyzer test set for the 220-325 GHz (WR3) frequency band. The test set utilizes Oleson Microwave Labs frequency extenders with the Agilent 8510C network analyzer. Two port on-wafer measurements are made with GGB Industries coplanar waveguide (CPW) probes. With this test set we have measured the WR3 band S-parameters of amplifiers on-wafer, and the characteristics of the CPW wafer probes. Results for a three stage InP HEMT amplifier show 10 dB gain at 235 GHz [1], and that of a single stage amplifier, 2.9 dB gain at 231 GHz. The approximate upper limit of loss per CPW probe range from 3.0 to 4.8 dB across the WR3 frequency band.

  2. The Celestial Reference Frame at X/Ka-band (8.4/32 GHz)

    NASA Technical Reports Server (NTRS)

    Jacobs, C. S.; Clark, J. E.; Heflin, M. B.; Skjerve, L. J.; Sovers, O. J.; Garcia-Miro, C.; Moll, V. E.; Horiuchi, S.

    2010-01-01

    A celestial reference frame at X/Kaband (8.4/32 GHz) has been constructed using fiftyone 24-hour sessions with the Deep Space Network. We report on observations which have detected 436 sources covering the full 24 hours of right ascension and declinations down to -45 deg. Comparison of this X/Ka-band frame to the S/X-band (2.3/8.4 GHz) ICRF2 shows wRMS agreement of 200 micro-arcsec ( mu as) in alpha cos delta and 290 mu as in delta. There is evidence for zonal errors at the 100 mu as level. Known errors include limited SNR, lack of phase calibration, troposphere mismodelling, and limited southern geometry. The motivations for extending the ICRF to frequencies above 8 GHz are to access more compact source morphology for improved frame stability, to provide calibrators for phase referencing, and to support spacecraft navigation at Ka-band.

  3. 47 CFR 15.252 - Operation of wideband vehicular radar systems within the bands 16.2-17.7 GHz and 23.12-29.0 GHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Operation of wideband vehicular radar systems within the bands 16.2-17.7 GHz and 23.12-29.0 GHz. 15.252 Section 15.252 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission...

  4. 47 CFR 15.252 - Operation of wideband vehicular radar systems within the bands 16.2-17.7 GHz and 23.12-29.0 GHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Operation of wideband vehicular radar systems within the bands 16.2-17.7 GHz and 23.12-29.0 GHz. 15.252 Section 15.252 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission...

  5. 47 CFR 15.252 - Operation of wideband vehicular radar systems within the bands 16.2-17.7 GHz and 23.12-29.0 GHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Operation of wideband vehicular radar systems within the bands 16.2-17.7 GHz and 23.12-29.0 GHz. 15.252 Section 15.252 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission...

  6. 47 CFR 15.252 - Operation of wideband vehicular radar systems within the bands 16.2-17.7 GHz and 23.12-29.0 GHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Operation of wideband vehicular radar systems within the bands 16.2-17.7 GHz and 23.12-29.0 GHz. 15.252 Section 15.252 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission...

  7. 47 CFR 74.32 - Operation in the 17.7-17.8 GHz and 17.8-19.7 GHz bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Operation in the 17.7-17.8 GHz and 17.8-19.7 GHz bands. 74.32 Section 74.32 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES General; Rules Applicable to All...

  8. 47 CFR 74.32 - Operation in the 17.7-17.8 GHz and 17.8-19.7 GHz bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 4 2014-10-01 2014-10-01 false Operation in the 17.7-17.8 GHz and 17.8-19.7 GHz bands. 74.32 Section 74.32 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES General; Rules Applicable to All...

  9. Ka-band (32-GHz) performance of 70-meter antennas in the Deep Space Network

    NASA Technical Reports Server (NTRS)

    Imbriale, W. A.; Bhanji, A. M.; Blank, S.; Lobb, V. B.; Levy, R.; Rocci, S. A.

    1987-01-01

    Two models are provided of the Deep Space Network (DSN) 70 m antenna performance at Ka-band (32 GHz) and, for comparison purposes, one at X-band (8.4 GHz). The baseline 70 m model represents expected X-band and Ka-band performance at the end of the currently ongoing 64 m to 70 m mechanical upgrade. The improved 70 m model represents two sets of Ka-band performance estimates (the X-band performance will not change) based on two separately developed improvement schemes: the first scheme, a mechanical approach, reduces tolerances of the panels and their settings, the reflector structure and subreflector, and the pointing and tracking system. The second, an electronic/mechanical approach, uses an array feed scheme to compensate fo lack of antenna stiffness, and improves panel settings using microwave holographic measuring techniques. Results are preliminary, due to remaining technical and cost uncertainties. However, there do not appear to be any serious difficulties in upgrading the baseline DSN 70 m antenna network to operate efficiently in an improved configuration at 32 GHz (Ka-band). This upgrade can be achieved by a conventional mechanical upgrade or by a mechanical/electronic combination. An electronically compensated array feed system is technically feasible, although it needs to be modeled and demonstrated. Similarly, the mechanical upgrade requires the development and demonstration of panel actuators, sensors, and an optical surveying system.

  10. A Compact 5.5 GHz Band-Rejected UWB Antenna Using Complementary Split Ring Resonators

    PubMed Central

    Islam, M. M.; Faruque, M. R. I.; Islam, M. T.

    2014-01-01

    A band-removal property employing microwave frequencies using complementary split ring resonators (CSRRs) is applied to design a compact UWB antenna wishing for the rejection of some frequency band, which is meanwhile exercised by the existing wireless applications. The reported antenna comprises optimization of a circular radiating patch, in which slotted complementary SRRs are implanted. It is printed on low dielectric FR4 substrate material fed by a partial ground plane and a microstrip line. Validated results exhibit that the reported antenna shows a wide bandwidth covering from 3.45 to more than 12 GHz, with a compact dimension of 22 × 26 mm2, and VSWR < 2, observing band elimination of 5.5 GHz WLAN band. PMID:24971379

  11. A compact 5.5 GHz band-rejected UWB antenna using complementary split ring resonators.

    PubMed

    Islam, M M; Faruque, M R I; Islam, M T

    2014-01-01

    A band-removal property employing microwave frequencies using complementary split ring resonators (CSRRs) is applied to design a compact UWB antenna wishing for the rejection of some frequency band, which is meanwhile exercised by the existing wireless applications. The reported antenna comprises optimization of a circular radiating patch, in which slotted complementary SRRs are implanted. It is printed on low dielectric FR4 substrate material fed by a partial ground plane and a microstrip line. Validated results exhibit that the reported antenna shows a wide bandwidth covering from 3.45 to more than 12 GHz, with a compact dimension of 22 × 26 mm(2), and VSWR < 2, observing band elimination of 5.5 GHz WLAN band. PMID:24971379

  12. 4 GHz band FET amplifier with the noise temperature of 55K at -50 deg C

    NASA Astrophysics Data System (ADS)

    Nakazawa, T.; Ogiso, K.; Takeda, F.; Miyazaki, S.; Nara, A.

    A thermoelectrically cooled 4 GHz band FET amplifier with a noise temperature of 55K developed as a low noise amplifier for satellite communications earth stations is described. It is pointed out that the method of broadband noise matching is used in the design. The difference between the maximum and minimum noise temperature within the frequency band of the amplifier is 3 K, a value consistent with the theoretical value.

  13. 78 FR 59844 - Operation in the 57-64 GHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-30

    ... (NPRM), 72 FR 39588, July 19, 2007, in this proceeding in response to a petition for rule making from... From the Federal Register Online via the Government Publishing Office ] FEDERAL COMMUNICATIONS COMMISSION 47 CFR Parts 2 and 15 Operation in the 57-64 GHz Band AGENCY: Federal Communications...

  14. 75 FR 9850 - Tank Level Probing Radars in the Frequency Band 77-81 GHz

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-04

    ... Proceedings, 63 FR 24121 (1998). Electronic Filers: Comments may be filed electronically using the Internet by... marketing equipment that complies with these conditions (e.g., Endress+Hauser GmbH+Co. KG (Endress+Hauser... TLPR operation in the 77-81 GHz band, subject to certain conditions. Endress+Hauser filed in support...

  15. 47 CFR 15.257 - Operation within the band 92-95 GHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... section are subject to the radiofrequency radiation exposure requirements specified in 47 CFR 1.1307(b), 2...-95 GHz bands, the emission levels shall not exceed the following: (1) The average power density of... meters from the radiating structure, and the peak power density of any emission shall not exceed 18...

  16. Use of the 30/20 GHz band by multipurpose satellite systems

    NASA Astrophysics Data System (ADS)

    McNeil, Stephen; Mimis, Vassilios; Sahay, Vishnu; Bowen, Robert

    The World Administrative Radio Conference (WARC) held in 1992 allocated the bands 19.7-20.2 GHz and 29.5-30.0 GHz to both the Mobile Satellite Service (MSS) and the Fixed Satellite Service (FSS) on a co-primary basis. An economic and flexible solution for the provision of both services is to place both payloads on one spacecraft. Some of the proposed applications of such a hybrid satellite network are described. It also examines the facility for spectrum sharing between the various applications and discusses the impact on coordination. It is concluded that the coordination process would not be more onerous than traditional FSS inter-satellite coordination.

  17. Use of the 30/20 GHz band by multipurpose satellite systems

    NASA Technical Reports Server (NTRS)

    Mcneil, Stephen; Mimis, Vassilios; Sahay, Vishnu; Bowen, Robert

    1993-01-01

    The World Administrative Radio Conference (WARC) held in 1992 allocated the bands 19.7-20.2 GHz and 29.5-30.0 GHz to both the Mobile Satellite Service (MSS) and the Fixed Satellite Service (FSS) on a co-primary basis. An economic and flexible solution for the provision of both services is to place both payloads on one spacecraft. Some of the proposed applications of such a hybrid satellite network are described. It also examines the facility for spectrum sharing between the various applications and discusses the impact on coordination. It is concluded that the coordination process would not be more onerous than traditional FSS inter-satellite coordination.

  18. Sensitivity study of ice crystal optical properties in the 874 GHz submillimeter band

    NASA Astrophysics Data System (ADS)

    Tang, Guanglin; Yang, Ping; Wu, Dong L.

    2016-07-01

    Testing of an 874 GHz submillimeter radiometer on meteorological satellites is being planned to improve ice water content retrievals. In this paper we study the optical properties of ice cloud particles in the 874 GHz band. The results show that the bulk scattering and absorption coefficients of an ensemble of ice cloud particles are sensitive to the particle shape and effective diameter, whereas the latter is also sensitive to temperature. The co-polar back scattering cross-section is not sensitive to particle shape, temperature, and the effective diameter in the range of 50-200 μm.

  19. Preliminary assessment of RFI impacts on TDRSS in the 2- to 2.3 GHz band

    NASA Technical Reports Server (NTRS)

    Lyttle, J. D.

    1974-01-01

    A study was conducted of the radio frequency bands and radio frequency interference (RFI) impacts on the TDR satellite. Quick look evaluations were performed on RFI conditions in the 136 to 138 MHz and 400.5 to 401.5 MHz bands. An approximate chronological account of the investigations and the intermediate findings are presented. The preliminary results of RFI evaluations in the nominally 2 to 2.3 GHz band. An analysis of the time interaction of user satellites with microwave radio-relay type communications beams as a source of RFI is included.

  20. The 2.2 GHz Surface Acoustic Wave (SAW) oscillator development Ku-band frequency source development

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Two 2.2 GHz SAW oscillators using aluminum nitride on sapphire (AlN/Al2O3) delay lines were fabricated. The oscillators were electronically temperature compensated and characterized. One of the oscillators was used as the frequency reference for the Ku band source; the second oscillator is available for continued evaluation. A 15 GHz frequency source was designed and fabricated. The 15 GHz source consists of a Ku band FET oscillator which is phase locked to the frequency multiplied (X7) output of the 2.2 GHz SAW reference source. The Ku band source was built using microstrip circuit designs, which are hybrid compatible. Two wafer runs of 2.2 GHz TED devices were fabricated and evaluated. The devices were mounted on microstrip test substrates and evaluated as 15 GHz divide by 7 circuits. The device evaluation indicated that in their present form the TED is not a practical circuit element.

  1. A New E-Band (60 - 90 GHz) Fourier Transform Millimeter-Wave Spectrometer

    NASA Astrophysics Data System (ADS)

    Halfen, D. T.; Ziurys, L. M.

    2013-06-01

    An E-band (60 - 90 GHz) cavity Fourier transform millimeter-wave (FTmmW) spectrometer system has been built and used for molecular measurements for the first time. These frequencies are the highest acheived using cavity FTM/mmW techniques. This new system, implemented as a millimeter frequency band on the current FTMW spectrometer of the Ziurys group, utilizes waveguide for radiation propagation and commercial E-band doublers and quadruplers to achieve continuous operation from 60 to 90 GHz. This system also employs an ALMA Band 2 low-noise amplifier (LNA), designed by NRAO. The Fabry-Perot cavity consists of two 170 mm diameter mirrors with a radius of curvature of 840 mm and a separation of 700 mm. The Q factor of the system is around 100,000. Using this system, the N_{Ka,Kc} = 4_{04} → 3_{03} transition of ScC_2 near 62 GHz has been recorded for the first time. These data, as well as other molecular lines, will be presented.

  2. Switchable S = 1/2 and J = 1/2 Rashba bands in ferroelectric halide perovskites

    PubMed Central

    Kim, Minsung; Im, Jino; Freeman, Arthur J.; Ihm, Jisoon; Jin, Hosub

    2014-01-01

    The Rashba effect is spin degeneracy lift originated from spin–orbit coupling under inversion symmetry breaking and has been intensively studied for spintronics applications. However, easily implementable methods and corresponding materials for directional controls of Rashba splitting are still lacking. Here, we propose organic–inorganic hybrid metal halide perovskites as 3D Rashba systems driven by bulk ferroelectricity. In these materials, it is shown that the helical direction of the angular momentum texture in the Rashba band can be controlled by external electric fields via ferroelectric switching. Our tight-binding analysis and first-principles calculations indicate that and Rashba bands directly coupled to ferroelectric polarization emerge at the valence and conduction band edges, respectively. The coexistence of two contrasting Rashba bands having different compositions of the spin and orbital angular momentum is a distinctive feature of these materials. With recent experimental evidence for the ferroelectric response, the halide perovskites will be, to our knowledge, the first practical realization of the ferroelectric-coupled Rashba effect, suggesting novel applications to spintronic devices. PMID:24785294

  3. High-purity 60GHz band millimeter-wave generation based on optically injected semiconductor laser under subharmonic microwave modulation.

    PubMed

    Fan, Li; Xia, Guangqiong; Chen, Jianjun; Tang, Xi; Liang, Qing; Wu, Zhengmao

    2016-08-01

    Based on an optically injected semiconductor laser (OISL) operating at period-one (P1) nonlinear dynamical state, high-purity millimeter-wave generation at 60 GHz band is experimentally demonstrated via 1/4 and 1/9 subharmonic microwave modulation (the order of subharmonic is with respect to the frequency fc of the acquired 60 GHz band millimeter-wave but not the fundamental frequency f0 of P1 oscillation). Optical injection is firstly used to drive a semiconductor laser into P1 state. For the OISL operates at P1 state with a fundamental frequency f0 = 49.43 GHz, by introducing 1/4 subharmonic modulation with a modulation frequency of fm = 15.32 GHz, a 60 GHz band millimeter-wave with central frequency fc = 61.28 GHz ( = 4fm) is experimentally generated, whose linewidth is below 1.6 kHz and SSB phase noise at offset frequency 10 kHz is about -96 dBc/Hz. For fm is varied between 13.58 GHz and 16.49 GHz, fc can be tuned from 54.32 GHz to 65.96 GHz under matched modulation power Pm. Moreover, for the OISL operates at P1 state with f0 = 45.02 GHz, a higher order subharmonic modulation (1/9) is introduced into the OISL for obtaining high-purity 60 GHz band microwave signal. With (fm, Pm) = (7.23 GHz, 13.00 dBm), a microwave signal at 65.07 GHz ( = 9fm) with a linewidth below 1.6 kHz and a SSB phase noise less than -98 dBc/Hz is experimentally generated. Also, the central frequency fc can be tuned in a certain range through adjusting fm and selecting matched Pm. PMID:27505789

  4. Modeling, design, fabrication, and testing of InP Gunn devices in the D-band (110 GHz - 170 GHz)

    NASA Technical Reports Server (NTRS)

    Kamoua, R.; Eisele, H.; East, J. R.; Haddad, G. I.; Munns, G.; Sherwin, M.

    1992-01-01

    The development of fundamental Gunn sources for D-band frequencies requires improvements of doping profiles, processing technology, and circuit design. We have developed a technology for fabricating InP Gunn diodes using an InGaAs etch-stop layer between the InP substrate and the device layers. The epitaxial layers were grown by CBE. During device processing, the substrate is completely removed. Substrateless devices with an n(+) InGaAs cap layer are expected to have reduced contact and series resistances, and skin effect losses. This technology gives better uniformity and control of the device geometry across the processed chip. InP Gunn devices with a 1.7 micron long active region (doping : 9 x 10(exp 15) cm(exp -3)) have been mounted on copper heat sinks. Two tapered leads were then bonded to the diode and to four quartz standoffs. As a preliminary result, an output power of 13 mW at 82 GHz was obtained. Based on these RF measurements, we determine appropriate material parameters to be used in the Ensemble Monte Carlo model. Subsequently, we use this model to design and evaluate the performance of InP Gunn Devices for D-band frequencies. Using the same technology, we are currently processing Gunn devices with a 1 micron long active region for operation at higher frequencies.

  5. Dual band 550/1200 GHz wideband spectrometer for planetary observation

    NASA Astrophysics Data System (ADS)

    Schlecht, Erich T.; Jamnejad, Vahraz; Jarnot, Robert F.; Thomas, Bertrand; Raffanti, Rick; Lin, Robert

    2012-10-01

    NASA and ESA are planning missions to Jupiter and its moons. There is strong interest in a submillimeter/Terahertz spectroscopic heterodyne instrument covering the bands 520 to 600 GHz and 1100 to 1300 GHz. Therefore, we are developing a prototype instrument incorporating unique features not previously developed for planetary instrumentation. These include (1) extremely wide, rapid tunability. The Herschel/HIFI astronomical instrument, is also wideband, but far larger. It incorporates a 3.5 meter telescope on a spacecraft massing over three tons orbiting near Earth, versus our 20 kg Jupiter spectrometer. Hence, we have developed a wideband low-phase-noise synthesizer pumping two Schottky diode LO multiplier chains outputting 520 to 600 and 550 to 650 GHz. Also based on Schottky diodes are (b) 550 and 1200 GHz room temperature mixers. The high frequency mixer is subharmonically pumped; the lower balanced fundamental. To analyze the IF signals from the mixers, (c) ASIC based digital polyphase spectrometers consuming only a few Watts each are being incorporated into the instrument. Finally, since signals for both receivers come from one telescope, we include a new (d) compact dual band low-loss optical bench. It uses the fact that each receiver accepts one polarization, making a polarizing beam splitter sufficient to split the beam with minimal loss.

  6. Spectrum response and analysis of 77 GHz band collective Thomson scattering diagnostic for bulk and fast ions in LHD plasmas

    NASA Astrophysics Data System (ADS)

    Nishiura, M.; Kubo, S.; Tanaka, K.; Seki, R.; Ogasawara, S.; Shimozuma, T.; Okada, K.; Kobayashi, S.; Mutoh, T.; Kawahata, K.; Watari, T.; LHD Experiment Group; Saito, T.; Tatematsu, Y.; Korsholm, S. B.; Salewski, M.

    2014-02-01

    A collective Thomson scattering (CTS) diagnostic was developed and used to measure the bulk and fast ions originating from 180 keV neutral beams in the Large Helical Device (LHD). Electromagnetic waves from a gyrotron at 77 GHz with 1 MW power output function as both the probe and electron cyclotron heating beam. To clarify the diagnostic applicability of the gyrotron in the 77 GHz frequency band, we investigated the dependence of the probe and receiver beam trajectories in plasmas with high electron densities of (4-5) × 1019 m-3 and low electron densities of (1-2) × 1019 m-3. At high density, a stray radiation component was observed in the CTS spectrum whereas it was negligibly small at low density. The CTS spectrum was measured and analysed after the in situ beam alignment using a beam scan. Qualitatively, the CTS spectrogram shows consistent response to ion temperatures of 1-2 keV for electron densities of (1-2) × 1019 m-3 and electron temperatures of 2-4 keV. The measured CTS spectrum shows an asymmetric shape at the foot of the bulk-ion region during the injection of 180 keV fast ions. This shape is explained by the fast-ion distribution in the velocity space (v‖, v⊥) based on Monte Carlo simulation results. The analysis method of the CTS spectra is used to evaluate the ion temperature and fast-ion velocity distribution from the measured CTS data.

  7. Mars Reconnaissance Orbiter Ka-band (32 GHz) Demonstration: Cruise Phase Operations

    NASA Technical Reports Server (NTRS)

    Shambayati, Shervin; Morabito, David; Border, James S.; Davarian, Faramaz; Lee, Dennis; Mendoza, Ricardo; Britcliffe, Michael; Weinreb, Sander

    2006-01-01

    The X-band (8.41 GHz) frequency currently used for deep space telecommunications is too narrow (50 MHz) to support future high rate missions. Because of this NASA has decided to transition to Ka-band (32 GHz) frequencies. As weather effects cause much larger fluctuations on Ka-band than on X-band, the traditional method of using a few dBs of margin to cover these fluctuations is wasteful of power for Ka-band; therefore, a different operations concept is needed for Ka-band links. As part of the development of the operations concept for Ka-band, NASA has implemented a fully functioning Ka-band communications suite on its Mars Reconnaissance Orbiter (MRO). This suite will be used during the primary science phase to develop and refine the Ka-band operations concept for deep space missions. In order to test the functional readiness of the spacecraft and the Deep Space Network's (DSN) readiness to support the demonstration activities a series of passes over DSN 34-m Beam Waveguide (BWG) antennas were scheduled during the cruise phase of the mission. MRO was launched on August 12, 2005 from Kennedy Space Center, Cape Canaveral, Florida, USA and went into Mars Orbit on March 10, 2006. A total of ten telemetry demonstration and one high gain antenna (HGA) calibration passes were allocated to the Ka-band demonstration. Furthermore, a number of "shadow" passes were also scheduled where, during a regular MRO track over a Ka-band capable antenna, Ka-band was identically configured as the X-band and tracked by the station. In addition, nine Ka-band delta differential one way ranging ((delta)DOR) passes were scheduled. During these passes, the spacecraft and the ground system were put through their respective paces. Among the highlights of these was setting a single day record for data return from a deep space spacecraft (133 Gbits) achieved during one 10-hour pass; achieving the highest data rate ever from a planetary mission (6 Mbps) and successfully demonstrating Ka-band DDOR

  8. A 1.2--Millimeter Broad--Band Polarimeter

    NASA Astrophysics Data System (ADS)

    Glenn, Jason; Walker, Christopher K.; Young, Erick T.

    1996-05-01

    We describe a 1.2--millimeter polarimeter to be used on the Steward Observatory and Max--Planck--Institut fur Radioastronomie 10--meter Submillimeter Telescope Observatory. The construction, performance parameters, and scientific purpose of the instrument are presented. The detector is a Ge bolometer with a Si absorber operated in a cavity cooled to 0.36 K by a liquid He(3) refrigerator. The bandpass has a central wavelength of 1.2 mm and a width of 0.3 mm. The system noise equivalent power is 1.5*E(-14) W Hz(-{1/2}) at 20 Hz. Polarimetric modulation is accomplished with a room temperature, rotating Rexolite half-wave plate. Unidirectional grooves provide the lambda /2 phase shift between the orthogonal senses of polarization. The polarization analyzer is a stationary, room temperature, unidirectional wire grid that transmits only one sense of polarization with 99% efficiency. The system polarimetric efficiency is 87% and the laboratory instrumental polarization is a well defined 3.7%. Detection of a 1% linear polarization is possible at the several sigma level. The primary scientific goal of this instrument is to probe the magnetic field orientations in the protostellar dust cores of molecular clouds. Non--spherical dust grains are aligned in the presence of a magnetic field resulting in linear polarization of the far--infrared thermal dust emission perpendicular to the magnetic field vector. Observed field orientations will be compared to protostellar molecular outflow orientations and magnetic fields on larger scales. With these comparisons we will assess the role of magnetic fields in cloud collapse and star formation.

  9. Q-Band (37-41 GHz) Satellite Beacon Architecture for RF Propagation Experiments

    NASA Technical Reports Server (NTRS)

    Simmons, Rainee N.; Wintucky, Edwin G.

    2012-01-01

    In this paper, the design of a beacon transmitter that will be flown as a hosted payload on a geostationary satellite to enable propagation experiments at Q-band (37-41 GHz) frequencies is presented. The beacon uses a phased locked loop stabilized dielectric resonator oscillator and a solid-state power amplifier to achieve the desired output power. The satellite beacon antenna is configured as an offset-fed cut-paraboloidal reflector.

  10. Q-Band (37 to 41 GHz) Satellite Beacon Architecture for RF Propagation Experiments

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.; Wintucky, Edwin G.

    2014-01-01

    In this paper, the design of a beacon transmitter that will be flown as a hosted payload on a geostationary satellite to enable propagation experiments at Q-band (37 to 41 GHz) frequencies is presented. The beacon uses a phased locked loop stabilized dielectric resonator oscillator and a solid-state power amplifier to achieve the desired output power. The satellite beacon antenna is configured as an offset-fed cutparaboloidal reflector.

  11. 47 CFR 25.250 - Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Sharing between NGSO MSS Feeder links Earth....250 Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands. (a) NGSO MSS applicants shall be licensed to operate in the 29.1-29.5 GHz band for...

  12. 47 CFR 25.250 - Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Sharing between NGSO MSS Feeder links Earth....250 Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands. (a) NGSO MSS applicants shall be licensed to operate in the 29.1-29.5 GHz band for...

  13. 47 CFR 25.250 - Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Sharing between NGSO MSS Feeder links Earth....250 Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands. (a) NGSO MSS applicants shall be licensed to operate in the 29.1-29.5 GHz band for...

  14. On-Wafer S-Parameter Measurements in the 325-508-GHz Band

    NASA Technical Reports Server (NTRS)

    Fung, King Man; Samonska, Lorene A.; Pukala, David M.; Dawson, Douglas E.; Kangaslahti, Pekka P.; Gaier, Todd C.; Lawrence, Charles; Boll, Greg; Mei, Xiaobing

    2011-01-01

    New circuits have been designed and fabricated with operating frequencies over 325 GHz. In order to measure S-parameters of these circuits, an extensive process of wafer dicing and packaging, and waveguide transition design, fabrication, and packaging would be required. This is a costly and time-consuming process before the circuit can be tested in waveguide. The new probes and calibration procedures will simplify the testing process. New on-wafer probes, and a procedure for their calibration, have been developed that allow fast and inexpensive S-parameter characterization of circuits in the 325 -508 -GHz frequency band. The on-wafer probes transition from rectangular waveguide to coplanar waveguide probe tips with 40- m nominal signal-to-ground pin pitch so as to allow for probing circuits on a wafer. The probes with bias tees have been optimized for minimal insertion loss and maximum return loss when placed on 50-ohm structures to allow for calibration. The calibration process has been developed using the Thru-Reflect-Line Agilent algorithm with JPL determined calibration structures and calibration coefficients for the algorithm. This new test capability is presently unique to JPL. With it, researchers will be able to better develop circuits such as low-noise amplifiers, power amplifiers, multipliers, and mixers for heterodyne receivers in the 325-508-GHz frequency band for remote sensing/spectroscopy.

  15. A deep/wide 1-2 GHz snapshot survey of SDSS Stripe 82 using the Karl G. Jansky Very Large Array in a compact hybrid configuration

    NASA Astrophysics Data System (ADS)

    Heywood, I.; Jarvis, M. J.; Baker, A. J.; Bannister, K. W.; Carvalho, C. S.; Hardcastle, M.; Hilton, M.; Moodley, K.; Smirnov, O. M.; Smith, D. J. B.; White, S. V.; Wollack, E. J.

    2016-08-01

    We have used the Karl G. Jansky Very Large Array to image ˜100 deg2 of SDSS Stripe 82 at 1-2 GHz. The survey consists of 1026 snapshot observations of 2.5 min duration, using the hybrid CnB configuration. The survey has good sensitivity to diffuse, low surface brightness structures and extended radio emission, making it highly synergistic with existing 1.4 GHz radio observations of the region. The principal data products are continuum images, with 16 × 10 arcsec resolution, and a catalogue containing 11 782 point and Gaussian components resulting from fits to the thresholded Stokes-I brightness distribution, forming approximately 8948 unique radio sources. The typical effective 1σ noise level is 88 μJy beam-1. Spectral index estimates are included, as derived from the 1 GHz of instantaneous bandwidth. Astrometric and photometric accuracy are in excellent agreement with existing narrowband observations. A large-scale simulation is used to investigate clean bias, which we extend into the spectral domain. Clean bias remains an issue for snapshot surveys with the VLA, affecting our total intensity measurements at the ˜1σ level. Statistical spectral index measurements are in good agreement with existing measurements derived from matching separate surveys at two frequencies. At flux densities below ˜35σ the median in-band spectral index measurements begin to exhibit a bias towards flatness that is dependent on both flux density and the intrinsic spectral index. In-band spectral curvature measurements are likely to be unreliable for all but the very brightest components. Image products and catalogues are publicly available via an FTP server.

  16. A deep/wide 1-2 GHz snapshot survey of SDSS Stripe 82 using the Karl G. Jansky Very Large Array in a compact hybrid configuration

    NASA Astrophysics Data System (ADS)

    Heywood, I.; Jarvis, M. J.; Baker, A. J.; Bannister, K. W.; Carvalho, C. S.; Hardcastle, M.; Hilton, M.; Moodley, K.; Smirnov, O. M.; Smith, D. J. B.; White, S. V.; Wollack, E. J.

    2016-08-01

    We have used the Karl G. Jansky Very Large Array to image ~100 sq. deg. of SDSS Stripe 82 at 1-2 GHz. The survey consists of 1,026 snapshot observations of 2.5 minutes duration, using the hybrid CnB configuration. The survey has good sensitivity to diffuse, low surface brightness structures and extended radio emission, making it highly synergistic with existing 1.4 GHz radio observations of the region. The principal data products are continuum images, with 16 x 10 arcsecond resolution, and a catalogue containing 11,782 point and Gaussian components resulting from fits to the thresholded Stokes-I brightness distribution, forming approximately 8,948 unique radio sources. The typical effective 1{\\sigma} noise level is 88 {\\mu}Jy / beam. Spectral index estimates are included, as derived from the 1 GHz of instantaneous bandwidth. Astrometric and photometric accuracy are in excellent agreement with existing narrowband observations. A large-scale simulation is used to investigate clean bias, which we extend into the spectral domain. Clean bias remains an issue for snapshot surveys with the VLA, affecting our total intensity measurements at the ~1{\\sigma} level. Statistical spectral index measurements are in good agreement with existing measurements derived from matching separate surveys at two frequencies. At flux densities below ~35{\\sigma} the median in-band spectral index measurements begin to exhibit a bias towards flatness that is dependent on both flux density and the intrinsic spectral index. In-band spectral curvature measurements are likely to be unreliable for all but the very brightest components. Image products and catalogues are publicly available via an FTP server.

  17. Sideband separating mixer for 600-720 GHz for ALMA band 9 upgrade

    NASA Astrophysics Data System (ADS)

    Khudchenko, Andrey; Hesper, Ronald; Baryshev, Andrey; Gerlofma, Gerrit; Barkhof, Jan; Adema, Joost; Mena, Patricio; Klapwijk, Teun; Spaans, Marco

    2012-09-01

    For high-frequency observational bands like ALMA (Atacama Large Millimeter Array) Band 9 (600—720 GHz), which tend to be dominated by atmospheric noise, implementation of sideband-separating mixers can reduce, up to a factor of two, the integration time needed to reach a certain signal-to-noise ratio for spectral line observations. Because of very high oversubscription factor for observation in ALMA Band 9, an upgrade of the current Double Sideband (DSB) mixer to a Two Sideband (2SB) configuration is a promising option for future ALMA development. Here we present a developed 2SB mixer and a modified cartridge design. The 2SB mixer includes a waveguide RF hybrid block, which have been produced on a micro-milling machine and equipped with standard Band 9 SIS mixer devices. These two SIS mixers have been separately tested in DSB mode. The SSB noise temperature is within the ALMA requirements of 336 K over 80% of the band, and 500 K over the entire band. The 2SB mixer has the sideband rejection ratio better than 12 dB over the full RF band, which is also well within the ALMA specifications of 10 dB.

  18. GHz repetition rate tabletop X-band photoinjector for free-electron laser applications

    SciTech Connect

    Le Sage, G.P.; Fochs, S.N.; Feng, H.X.C.

    1995-12-31

    A 1-1/2 cell {pi}-mode X-bend (8.568 GHz) photoinjector system capable of producing trains of up to one hundred, 1 nC, 1ps, 5 MeV, {epsilon}{sub n} < 2.5 {pi} mm-mrad photoelectron bunches, at a micropulse repetition rate of 1-10 Hz, is currently under development at LLNL, in the UC Davis DAS coherent millimeter-wave group. The system is powered by a 20 MW, 8.568 GHz SLAC development klystron. The system also uses a Cs{sub 2}Te (Cesium Telluride) photocathode which has a quantum efficiency > 5% in the UV (210 nm). The compact UV laser system is composed of a synchronously modelocked AlGaAs semiconductor laser oscillator which produces pulses with a duration of 250 fs and 100 pJ energy at 830 nm, at a repetion rate of 2.142 GHz with less 400 is jitter, a 5 GHz bandwidth Lithium Niobate Mach-Zender fiber modulator, an 8-pass, 10{sup 6} gain, TiAl{sub 2}O{sub 3} (Titanium:Sapphire) chirped pulse amplifier, and 2 BBO frequency doublers in series to quadruple the laser frequency into the UV (207 nm).

  19. Single spin optically detected magnetic resonance with 60-90 GHz (E-band) microwave resonators.

    PubMed

    Aslam, Nabeel; Pfender, Matthias; Stöhr, Rainer; Neumann, Philipp; Scheffler, Marc; Sumiya, Hitoshi; Abe, Hiroshi; Onoda, Shinobu; Ohshima, Takeshi; Isoya, Junichi; Wrachtrup, Jörg

    2015-06-01

    Magnetic resonance with ensembles of electron spins is commonly performed around 10 GHz, but also at frequencies above 240 GHz and in corresponding magnetic fields of over 9 T. However, experiments with single electron and nuclear spins so far only reach into frequency ranges of several 10 GHz, where existing coplanar waveguide structures for microwave (MW) delivery are compatible with single spin readout techniques (e.g., electrical or optical readout). Here, we explore the frequency range up to 90 GHz, with magnetic fields of up to ≈3 T for single spin magnetic resonance in conjunction with optical spin readout. To this end, we develop MW resonators with optical single spin access. In our case, rectangular 60-90 GHz (E-band) waveguides guarantee low-loss supply of microwaves to the resonators. Three dimensional cavities, as well as coplanar waveguide resonators, enhance MW fields by spatial and spectral confinement with a MW efficiency of 1.36 mT/√W. We utilize single nitrogen vacancy (NV) centers as hosts for optically accessible spins and show that their properties regarding optical spin readout known from smaller fields (<0.65 T) are retained up to fields of 3 T. In addition, we demonstrate coherent control of single nuclear spins under these conditions. Furthermore, our results extend the applicable magnetic field range of a single spin magnetic field sensor. Regarding spin based quantum registers, high fields lead to a purer product basis of electron and nuclear spins, which promises improved spin lifetimes. For example, during continuous single-shot readout, the (14)N nuclear spin shows second-long longitudinal relaxation times. PMID:26133855

  20. 0.8-5.2GHz Broad-Band SiGe-MMIC Quadrature Mixer for Software Defined Radio Receiver

    NASA Astrophysics Data System (ADS)

    Murakami, Keishi; Suematsu, Noriharu; Tsutsumi, Koji; Kanazawa, Gakushi; Sekine, Tomotsugu; Kubo, Hiroshi; Isota, Yoji

    For the next generation wireless terminals used in the software defined radio (SDR), multi-band / multi-mode transceivers and their MMIC are required which cover the wide RF frequency range from several hundreds MHz up to several GHz. In this paper, 0.8-5.2GHz broad-band SiGe-MMIC quadrature mixer (Q-MIX) for multi-band / multi-mode direct conversion receiver has been developed. By using a static type frequency divider as a 90 degrees local (LO) power divider, measured error vector magnitude (EVM) of less than 3.1% can be achieved in the cases of 0.8/2.1GHz W-CDMA and 5.2GHz wireless Local Area Network (LAN) (IEEE 802.11a) reception. This Q-MIX also shows broad-band characteristic for base-band signal and is applicable for 4G cellular. By using fabricated Q-MIX, a multi-band / multi-mode (1.9GHz (3rd generation cellular (W-CDMA)) / 5.2GHz (4th generation cellular (Multi-Carrier (MC)-CDMA))) receiver has been developed and it has firstly demonstrated the successful reception of motion picture via W-CDMA and MC-CDMA.

  1. The Potential for a Ka-band (32 GHz) Worldwide VLBI Network

    NASA Astrophysics Data System (ADS)

    Jacobs, C. S.; Bach, U.; Colomer, F.; Garcá-Miró, C.; Gómez-González, J.; Gulyaev, S.; Horiuchi, S.; Ichikawa, R.; Kraus, A.; Kronschnabl, G.; López-Fernández, J. A.; Lovell, J.; Majid, W.; T; Natusch; Neidhardt, A.; Phillips, C.; Porcas, R.; Romero-Wolf, A.; Saldana, L.; Schreiber, U.; Sotuela, I.; Takeuchi, H.; Trinh, J.; Tzioumis, A.; de Vincente, P.; Zharov, V.

    2012-12-01

    Ka-band (32 GHz, 9 mm) Very Long Baseline Interferometric (VLBI) networking has now begun and has tremendous potential for expansion over the next few years. Ka-band VLBI astrometry from NASA's Deep Space Network has already developed a catalog of 470 observable sources with highly accurate positions. Now, several antennas worldwide are planning or are considering adding Ka-band VLBI capability. Thus, there is now an opportunity to create a worldwide Ka-band network with potential for high resolution imaging and astrometry. With baselines approaching a Giga-lambda, a Ka-band network would be able to probe source structure at the nano-radian (200 as) level (100X better than Hubble) and thus gain insight into the astrophysics of the most compact regions of emission in active galactic nuclei. We discuss the advantages of Ka-band, show the known sources and candidates, simulate projected baseline (uv) coverage, and discuss potential radio frequency feeds. The combination of these elements demonstrates the feasibility of a worldwide Ka network within the next few years.

  2. The Potential for a Ka-band (32 GHz) Worldwide VLBI Network

    NASA Technical Reports Server (NTRS)

    Jacobs, C. S.; Bach, U.; Colomer, F.; Garcia-Miro, C.; Gomez-Gonzalez, J.; Gulyaev, S.; Horiuchi, S.; Ichikawa, R.; Kraus, A.; Kronschnabl, G.; Lopez-Fernandez, J. A.; Lovell, J.; Majid, W.; Natusch, T.; Neidhardt, A.; Phillips, C.; Porcas, R.; Romero-Wolf, A.; Saldana, L.; Schreiber, U.; Sotuela, I.; Takeuchi, H.; Trinh, J.; Tzioumis, A.; deVincente, P.

    2012-01-01

    Ka-band (32 GHz, 9mm) Very Long Baseline Interferometric (VLBI) networking has now begun and has tremendous potential for expansion over the next few years. Ka-band VLBI astrometry from NASA's Deep Space Network has already developed a catalog of 470 observable sources with highly accurate positions. Now, several antennas worldwide are planning or are considering adding Ka-band VLBI capability. Thus, there is now an opportunity to create a worldwide Ka-band network with potential for high resolution imaging and astrometry. With baselines approaching a Giga-lambda, a Ka-band network would be able to probe source structure at the nano-radian (200 as) level ( 100X better than Hubble) and thus gain insight into the astrophysics of the most compact regions of emission in active galactic nuclei. We discuss the advantages of Ka-band, show the known sources and candidates, simulate projected baseline (uv) coverage, and discuss potential radio frequency feeds. The combination of these elements demonstrates the feasibility of a worldwide Ka network within the next few years!

  3. Design of 4x1 microstrip patch antenna array for 5.8 GHz ISM band applications

    NASA Astrophysics Data System (ADS)

    Valjibhai, Gohil Jayesh; Bhatia, Deepak

    2013-01-01

    This paper describes the new design of four element antenna array using corporate feed technique. The proposed antenna array is developed on the Rogers 5880 dielectric material. The antenna array works on 5.8 GHz ISM band. The industrial, scientific and medical (ISM) radio bands are radio bands (portions of the radio spectrum) reserved internationally for the use of radio frequency (RF) energy for industrial, scientific and medical purposes other than communications. The array antennas have VSWR < 1.6 from 5.725 - 5.875 GHz. The simulated return loss characteristic of the antenna array is - 39.3 dB at 5.8 GHz. The gain of the antenna array is 12.3 dB achieved. The directivity of the broadside radiation pattern is 12.7 dBi at the 5.8 GHz operating frequency. The antenna array is simulated using High frequency structure simulation software.

  4. Initial Performance of Bicep3: A Degree Angular Scale 95 GHz Band Polarimeter

    NASA Astrophysics Data System (ADS)

    Wu, W. L. K.; Ade, P. A. R.; Ahmed, Z.; Alexander, K. D.; Amiri, M.; Barkats, D.; Benton, S. J.; Bischoff, C. A.; Bock, J. J.; Bowens-Rubin, R.; Buder, I.; Bullock, E.; Buza, V.; Connors, J. A.; Filippini, J. P.; Fliescher, S.; Grayson, J. A.; Halpern, M.; Harrison, S. A.; Hilton, G. C.; Hristov, V. V.; Hui, H.; Irwin, K. D.; Kang, J.; Karkare, K. S.; Karpel, E.; Kefeli, S.; Kernasovskiy, S. A.; Kovac, J. M.; Kuo, C. L.; Megerian, K. G.; Netterfield, C. B.; Nguyen, H. T.; O'Brient, R.; Ogburn, R. W.; Pryke, C.; Reintsema, C. D.; Richter, S.; Sorensen, C.; Staniszewski, Z. K.; Steinbach, B.; Sudiwala, R. V.; Teply, G. P.; Thompson, K. L.; Tolan, J. E.; Tucker, C. E.; Turner, A. D.; Vieregg, A. G.; Weber, A. C.; Wiebe, D. V.; Willmert, J.; Yoon, K. W.

    2016-08-01

    Bicep3 is a 550-mm aperture telescope with cold, on-axis, refractive optics designed to observe at the 95-GHz band from the South Pole. It is the newest member of the Bicep/ Keck family of inflationary probes specifically designed to measure the polarization of the cosmic microwave background (CMB) at degree angular scales. Bicep3 is designed to house 1280 dual-polarization pixels, which, when fully populated, totals to ˜ 9× the number of pixels in a single Keck 95-GHz receiver, thus further advancing the Bicep/ Keck program's 95 GHz mapping speed. Bicep3 was deployed during the austral summer of 2014-2015 with nine detector tiles, to be increased to its full capacity of 20 in the second season. After instrument characterization, measurements were taken, and CMB observation commenced in April 2015. Together with multi-frequency observation data from Planck, Bicep2, and the Keck Array, Bicep3 is projected to set upper limits on the tensor-to-scalar ratio to r lesssim 0.03 at 95 % C.L.

  5. Initial Performance of uc(Bicep3): A Degree Angular Scale 95 GHz Band Polarimeter

    NASA Astrophysics Data System (ADS)

    Wu, W. L. K.; Ade, P. A. R.; Ahmed, Z.; Alexander, K. D.; Amiri, M.; Barkats, D.; Benton, S. J.; Bischoff, C. A.; Bock, J. J.; Bowens-Rubin, R.; Buder, I.; Bullock, E.; Buza, V.; Connors, J. A.; Filippini, J. P.; Fliescher, S.; Grayson, J. A.; Halpern, M.; Harrison, S. A.; Hilton, G. C.; Hristov, V. V.; Hui, H.; Irwin, K. D.; Kang, J.; Karkare, K. S.; Karpel, E.; Kefeli, S.; Kernasovskiy, S. A.; Kovac, J. M.; Kuo, C. L.; Megerian, K. G.; Netterfield, C. B.; Nguyen, H. T.; O'Brient, R.; Ogburn, R. W.; Pryke, C.; Reintsema, C. D.; Richter, S.; Sorensen, C.; Staniszewski, Z. K.; Steinbach, B.; Sudiwala, R. V.; Teply, G. P.; Thompson, K. L.; Tolan, J. E.; Tucker, C. E.; Turner, A. D.; Vieregg, A. G.; Weber, A. C.; Wiebe, D. V.; Willmert, J.; Yoon, K. W.

    2015-12-01

    uc(Bicep3) is a 550-mm aperture telescope with cold, on-axis, refractive optics designed to observe at the 95-GHz band from the South Pole. It is the newest member of the uc(Bicep)/Keck family of inflationary probes specifically designed to measure the polarization of the cosmic microwave background (CMB) at degree angular scales. uc(Bicep3) is designed to house 1280 dual-polarization pixels, which, when fully populated, totals to ˜ 9× the number of pixels in a single Keck 95-GHz receiver, thus further advancing the uc(Bicep)/Keck program's 95 GHz mapping speed. uc(Bicep3) was deployed during the austral summer of 2014-2015 with nine detector tiles, to be increased to its full capacity of 20 in the second season. After instrument characterization, measurements were taken, and CMB observation commenced in April 2015. Together with multi-frequency observation data from Planck, uc(Bicep2), and the Keck Array, uc(Bicep3) is projected to set upper limits on the tensor-to-scalar ratio to r ≲ 0.03 at 95 % C.L.

  6. Three MMIC Amplifiers for the 120-to-200 GHz Frequency Band

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene; Schmitz, Adele

    2009-01-01

    Closely following the development reported in the immediately preceding article, three new monolithic microwave integrated circuit (MMIC) amplifiers that would operate in the 120-to-200-GHz frequency band have been designed and are under construction at this writing. The active devices in these amplifiers are InP high-electron-mobility transistors (HEMTs). These amplifiers (see figure) are denoted the LSLNA150, the LSA200, and the LSA185, respectively. Like the amplifiers reported in the immediately preceding article, the LSLNA150 (1) is intended to be a prototype of low-noise amplifiers (LNAs) to be incorporated into spaceborne instruments for sensing cosmic microwave background radiation and (2) has potential for terrestrial use in electronic test equipment, passive millimeter-wave imaging systems, radar receivers, communication receivers, and systems for detecting hidden weapons. The HEMTs in this amplifier were fabricated according to 0.08- m design rules of a commercial product line of InP HEMT MMICs at HRL Laboratories, LLC, with a gate geometry of 2 fingers, each 15 m wide. On the basis of computational simulations, this amplifier is designed to afford at least 15 dB of gain, with a noise figure of no more than about 6 dB, at frequencies from 120 to 160 GHz. The measured results of the amplifier are shown next to the chip photo, with a gain of 16 dB at 150 GHz. Noise figure work is ongoing. The LSA200 and the LSA185 are intended to be prototypes of transmitting power amplifiers for use at frequencies between about 180 and about 200 GHz. These amplifiers have also been fabricated according to rules of the aforesaid commercial product line of InP HEMT MMICs, except that the HEMTs in these amplifiers are characterized by a gate geometry of 4 fingers, each 37 m wide. The measured peak performance of the LSA200 is characterized by a gain of about 1.4 dB at a frequency of 190 GHz; the measured peak performance of the LSA185 is characterized by a gain of about 2

  7. High-Power Ka-Band Transmission Line with a Frequency Bandwidth of 1 GHZ

    NASA Astrophysics Data System (ADS)

    Bogdashov, A. A.; Denisov, G. G.; Samsonov, S. V.; Gachev, I. G.; Dominyuk, Ya. V.; Murzin, V. N.; Levitan, B. A.

    2016-03-01

    We present experimental results on a high-power transmission line from the broadband pulsed Ka-band gyro-TWT to the phased antenna array. The transmission line is designed to operate in a pulse-periodic regime with a pulse width of up to 250 μs, a duty factor of 8, and an average output power of up to 15 kW. Amplitude-frequency and phase-frequency characteristics of the transmission line were measured at a low power level. It is shown that the nonlinearity of the phase-frequency characteristic does not exceed ±10° in the 34 ± 0.5 GHz frequency band.

  8. Link Design and Planning for Mars Reconnaissance Orbiter (MRO) Ka-band (32 GHz) Telecom Demonstration

    NASA Technical Reports Server (NTRS)

    Shambayati, Shervin; Davarian, Faramaz; Morabito, David

    2004-01-01

    NASA is planning an engineering telemetry demonstration with Mars Reconnaissance Orbiter (MRO). Capabilities of Ka-band (32 GHz) for use with deep space mission are demonstrated using the link optimization algorithms and weather forecasting. Furthermore, based on the performance of previous deep space missions with Ka-band downlink capabilities, experiment plans are developed for telemetry operations during superior solar conjunction. A general overview of the demonstration is given followed by a description of the mission planning during cruise, the primary science mission and superior conjunction. As part of the primary science mission planning the expected data return for various data optimization methods is calculated. These results indicate that, given MRO's data rates, a link optimized to use of at most two data rates, subject to a minimum availability of 90%, performs almost as well as a link with no limits on the number of data rates subject to the same minimum availability.

  9. Development of a 10 MW, 91 GHz Gyroklystron for W-Band Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Nielson, Jeff; Ives, Lawrence; Lawson, Wes; Arjona, Melany

    1999-11-01

    An international effort is underway to design advanced linear electron-positron colliders with mass energies beyond 1 TeV. High power RF sources are required to drive accelerators operating at frequencies as high as W-Band. Calabazas Creek Research, Inc. is funded by the U.S. Department of Energy to design a 10 MW, second harmonic, gyroklystron at 91 GHz. The program is coordinated with W-Band accelerator research at the Stanford Linear Accelerator Center. The goal is to achieve an electronic efficiency of 45presentation will describe the proposed electron gun, three cavity RF circuit, magnetic circuit, and input and output couplers. Current simulation results will be presented and design tradeoffs will be discussed.

  10. Underwater Wireless Sensor Communications in the 2.4 GHz ISM Frequency Band

    PubMed Central

    Lloret, Jaime; Sendra, Sandra; Ardid, Miguel; Rodrigues, Joel J. P. C.

    2012-01-01

    One of the main problems in underwater communications is the low data rate available due to the use of low frequencies. Moreover, there are many problems inherent to the medium such as reflections, refraction, energy dispersion, etc., that greatly degrade communication between devices. In some cases, wireless sensors must be placed quite close to each other in order to take more accurate measurements from the water while having high communication bandwidth. In these cases, while most researchers focus their efforts on increasing the data rate for low frequencies, we propose the use of the 2.4 GHz ISM frequency band in these special cases. In this paper, we show our wireless sensor node deployment and its performance obtained from a real scenario and measures taken for different frequencies, modulations and data transfer rates. The performed tests show the maximum distance between sensors, the number of lost packets and the average round trip time. Based on our measurements, we provide some experimental models of underwater communication in fresh water using EM waves in the 2.4 GHz ISM frequency band. Finally, we compare our communication system proposal with the existing systems. Although our proposal provides short communication distances, it provides high data transfer rates. It can be used for precision monitoring in applications such as contaminated ecosystems or for device communicate at high depth. PMID:22666029

  11. Underwater wireless sensor communications in the 2.4 GHz ISM frequency band.

    PubMed

    Lloret, Jaime; Sendra, Sandra; Ardid, Miguel; Rodrigues, Joel J P C

    2012-01-01

    One of the main problems in underwater communications is the low data rate available due to the use of low frequencies. Moreover, there are many problems inherent to the medium such as reflections, refraction, energy dispersion, etc., that greatly degrade communication between devices. In some cases, wireless sensors must be placed quite close to each other in order to take more accurate measurements from the water while having high communication bandwidth. In these cases, while most researchers focus their efforts on increasing the data rate for low frequencies, we propose the use of the 2.4 GHz ISM frequency band in these special cases. In this paper, we show our wireless sensor node deployment and its performance obtained from a real scenario and measures taken for different frequencies, modulations and data transfer rates. The performed tests show the maximum distance between sensors, the number of lost packets and the average round trip time. Based on our measurements, we provide some experimental models of underwater communication in fresh water using EM waves in the 2.4 GHz ISM frequency band. Finally, we compare our communication system proposal with the existing systems. Although our proposal provides short communication distances, it provides high data transfer rates. It can be used for precision monitoring in applications such as contaminated ecosystems or for device communicate at high depth. PMID:22666029

  12. A 1.1-1.9 GHz SETI SURVEY OF THE KEPLER FIELD. I. A SEARCH FOR NARROW-BAND EMISSION FROM SELECT TARGETS

    SciTech Connect

    Siemion, Andrew P. V.; Korpela, Eric; Werthimer, Dan; Cobb, Jeff; Lebofsky, Matt; Marcy, Geoffrey W.; Demorest, Paul; Maddalena, Ron J.; Langston, Glen; Howard, Andrew W.; Tarter, Jill

    2013-04-10

    We present a targeted search for narrow-band (<5 Hz) drifting sinusoidal radio emission from 86 stars in the Kepler field hosting confirmed or candidate exoplanets. Radio emission less than 5 Hz in spectral extent is currently known to only arise from artificial sources. The stars searched were chosen based on the properties of their putative exoplanets, including stars hosting candidates with 380 K > T{sub eq} > 230 K, stars with five or more detected candidates or stars with a super-Earth (R{sub p} < 3 R{sub Circled-Plus }) in a >50 day orbit. Baseband voltage data across the entire band between 1.1 and 1.9 GHz were recorded at the Robert C. Byrd Green Bank Telescope between 2011 February and April and subsequently searched offline. No signals of extraterrestrial origin were found. We estimate that fewer than {approx}1% of transiting exoplanet systems host technological civilizations that are radio loud in narrow-band emission between 1 and 2 GHz at an equivalent isotropically radiated power (EIRP) of {approx}1.5 Multiplication-Sign 10{sup 21} erg s{sup -1}, approximately eight times the peak EIRP of the Arecibo Planetary Radar, and we limit the number of 1-2 GHz narrow-band-radio-loud Kardashev type II civilizations in the Milky Way to be <10{sup -6} M{sub Sun }{sup -1}. Here we describe our observations, data reduction procedures and results.

  13. A 1.1-1.9 GHz SETI Survey of the Kepler Field. I. A Search for Narrow-band Emission from Select Targets

    NASA Astrophysics Data System (ADS)

    Siemion, Andrew P. V.; Demorest, Paul; Korpela, Eric; Maddalena, Ron J.; Werthimer, Dan; Cobb, Jeff; Howard, Andrew W.; Langston, Glen; Lebofsky, Matt; Marcy, Geoffrey W.; Tarter, Jill

    2013-04-01

    We present a targeted search for narrow-band (<5 Hz) drifting sinusoidal radio emission from 86 stars in the Kepler field hosting confirmed or candidate exoplanets. Radio emission less than 5 Hz in spectral extent is currently known to only arise from artificial sources. The stars searched were chosen based on the properties of their putative exoplanets, including stars hosting candidates with 380 K > T eq > 230 K, stars with five or more detected candidates or stars with a super-Earth (R p < 3 R ⊕) in a >50 day orbit. Baseband voltage data across the entire band between 1.1 and 1.9 GHz were recorded at the Robert C. Byrd Green Bank Telescope between 2011 February and April and subsequently searched offline. No signals of extraterrestrial origin were found. We estimate that fewer than ~1% of transiting exoplanet systems host technological civilizations that are radio loud in narrow-band emission between 1 and 2 GHz at an equivalent isotropically radiated power (EIRP) of ~1.5 × 1021 erg s-1, approximately eight times the peak EIRP of the Arecibo Planetary Radar, and we limit the number of 1-2 GHz narrow-band-radio-loud Kardashev type II civilizations in the Milky Way to be {<}10^{-6}\\ M^{-1}_\\odot. Here we describe our observations, data reduction procedures and results.

  14. Design and Realization of a Planar Ultrawideband Antenna with Notch Band at 3.5 GHz

    PubMed Central

    2014-01-01

    A small antenna with single notch band at 3.5 GHz is designed for ultrawideband (UWB) communication applications. The fabricated antenna comprises a radiating monopole element and a perfectly conducting ground plane with a wide slot. To achieve a notch band at 3.5 GHz, a parasitic element has been inserted in the same plane of the substrate along with the radiating patch. Experimental results shows that, by properly adjusting the position of the parasitic element, the designed antenna can achieve an ultrawide operating band of 3.04 to 11 GHz with a notched band operating at 3.31–3.84 GHz. Moreover, the proposed antenna achieved a good gain except at the notched band and exhibits symmetric radiation patterns throughout the operating band. The prototype of the proposed antenna possesses a very compact size and uses simple structures to attain the stop band characteristic with an aim to lessen the interference between UWB and worldwide interoperability for microwave access (WiMAX) band. PMID:25133245

  15. Single-Chip T/R Module for 1.2 GHz

    NASA Technical Reports Server (NTRS)

    Moussessian, Alina; Mojarradi, Mohammad; Johnson, Travis; Davis, John; Grigorian, Edwin; Hoffman, James; Caro, Edward; Kuhn, William

    2006-01-01

    A single-chip CMOS-based (complementary-metal-oxide-semiconductorbased) transmit/receive (T/R) module is being developed for L-band radar systems. Previous T/R module implementations required multiple chips employing different technologies (GaAs, Si, and others) combined with off-chip transmission lines and discrete components including circulators. The new design eliminates the bulky circulator, significantly reducing the size and mass of the T/R module. Compared to multi-chip designs, the single-chip CMOS can be implemented with lower cost. These innovations enable cost-effective realization of advanced phased array and synthetic aperture radar systems that require integration of thousands of T/R modules. The circulator is a ferromagnetic device that directs the flow of the RF (radio frequency) power during transmission and reception. During transmission, the circulator delivers the transmitted power from the amplifier to the antenna, while preventing it from damaging the sensitive receiver circuitry. During reception, the circulator directs the energy from the antenna to the low-noise amplifier (LNA) while isolating the output of the power amplifier (PA). In principle, a circulator could be replaced by series transistors acting as electronic switches. However, in practice, the integration of conventional series transistors into a T/R chip introduces significant losses and noise. The prototype single-chip T/R module contains integrated transistor switches, but not connected in series; instead, they are connected in a shunt configuration with resonant circuits (see figure). The shunt/resonant circuit topology not only reduces the losses associated with conventional semiconductor switches but also provides beneficial transformation of impedances for the PA and the LNA. It provides full singlepole/ double-throw switching for the antenna, isolating the LNA from the transmitted signal and isolating the PA from the received signal. During reception, the voltage on

  16. Design and fabrication of 5 GHz band pass filter using circle-type HTS bulk resonator

    NASA Astrophysics Data System (ADS)

    Saito, A.; Teshima, H.; Ono, S.; Hirano, H.; Hirano, S.; Ohshima, S.

    2007-10-01

    We designed and fabricated a transmit band pass filter (BPF) using circle-type high temperature superconductor (HTS) bulk resonators. A Dy-Ba-Cu-O bulk was fabricated using a modified quench and melt growth (QMG) process and cut into specimens of 8.40 and 8.44 mm in diameter and 0.5 mm thick for use as the HTS bulk resonators. A three-pole stripline (SL) BPF was designed based on a Chebyshev function and the frequency response and electromagnetic field of the filter were simulated using a three-dimensional electromagnetic field simulator. From the results of the simulation, the center frequency, bandwidth, insertion loss, and ripple of the designed filter were 4.97 GHz, 100 MHz, 0.03 dB, and 0.048 dB, respectively. In the experimental results on the actual fabricated filter, the filtering response was clearly observed; however, the center frequency of 5.46 GHz was higher than that of the simulation. The simulated maximum surface current in the resonators of the SL filter was approximately 86% smaller than that of a conventional hairpin filter. Furthermore, the measured response of the Dy-Ba-Cu-O bulk filter at an input power of 20 dBm was almost the same as that at 0 dBm. These results mean that an SL filter using a Dy-Ba-Cu-O bulk resonator may be practicable as a high-power transmit BPF.

  17. A 60GHz-Band 3-Dimensional System-in-Package Transmitter Module with Integrated Antenna

    NASA Astrophysics Data System (ADS)

    Suematsu, Noriharu; Yoshida, Satoshi; Tanifuji, Shoichi; Kameda, Suguru; Takagi, Tadashi; Tsubouchi, Kazuo

    A low cost, ultra small Radio Frequency (RF) transceiver module with integrated antenna is one of the key technologies for short range millimeter-wave wireless communication. This paper describes a 60GHz-band transmitter module with integrated dipole antenna. The module consists of three pieces of low-cost organic resin substrate. These substrates are vertically stacked by employing Cu ball bonding 3-dimensional (3-D) system-in-package (SiP) technology and the MMIC's are mounted on each organic substrates by using Au-stud bump bonding (SBB) technique. The planer dipole antenna is fabricated on the top of the stacked organic substrate to avoid the influence of the grounding metal on the base substrate. At 63GHz, maximum actual gain of 6.0dBi is obtained for fabricated planar dipole antenna. The measured radiation patterns are agreed with the electro-magnetic (EM) simulated result, therefore the other RF portion of the 3-D front-end module, such as flip chip mounted IC's on the top surface of the module, does not affect the antenna characteristics. The results show the feasibility of millimeter-wave low cost, ultra small antenna integrated module using stacked organic substrates.

  18. SCPC terminal and signal strength measuring apparatus for 30/20 GHz frequency band

    NASA Astrophysics Data System (ADS)

    Iguchi, M.; Nishiyama, I.; Saruwatari, T.; Takahashi, T.; Cho, T.

    1982-03-01

    In the Japanese Medium Capacity Communications Satellite (CS) for Experimental Purpose project, a delta-M-PSK-SCPC system operating in the 30/20 GHz band is planned in order to establish a small capacity communications system. A small-sized earth station and SCPC terminal equipment have been successfully developed. The earth station consists of an antenna with a diameter of 2 m, an IMPATT high power amplifier, and a GaAs FET low noise receiver. G/T and EIRP of the station are 22 dB/K and 58.5 dBW, respectively. The SCPC terminal consists of a delta-M-CODEC for voice transmission, a data interface, and a four-phase PSK modulator/demodulator operating at 64 kbps. A signal strength measuring apparatus has been developed for measuring the strength of the 20 GHz beacon signal from the CS. This apparatus is used to obtain data about propagation characteristics, such as rainfall attenuation.

  19. A cooperative transponder system for improved traffic safety, localizing road users in the 5 GHz band

    NASA Astrophysics Data System (ADS)

    Schaffer, B.; Kalverkamp, G.; Chaabane, M.; Biebl, E. M.

    2012-09-01

    We present a multi-user cooperative mobile transponder system which enables cars to localize pedestrians, bicyclists and other road users in order to improve traffic safety. The system operates at a center frequency of 5.768 GHz, offering the ability to test precision localization technology at frequencies close to the newly designated automotive safety related bands around 5.9 GHz. By carrying out a roundtrip time of flight measurement, the sensor can determine the distance from the onboard localization unit of a car to a road user who is equipped with an active transponder, employing the idea of a secondary radar and pulse compression. The onboard unit sends out a pseudo noise coded interrogation pulse, which is answered by one or more transponders after a short waiting time. Each transponder uses a different waiting time in order to allow for time division multiple access. We present the system setup as well as range measurement results, achieving an accuracy up to centimeters for the distance measurement and a range in the order of hundred meters. We also discuss the effect of clock drift and offset on distance accuracy for different waiting times and show how the system can be improved to further increase precision in a multiuser environment.

  20. Optical multi-coset sampling of GHz-band chirped signals

    NASA Astrophysics Data System (ADS)

    Valley, George C.; Sefler, George A.; Shaw, T. J.; Smith, Stephen L.

    2015-03-01

    Direct digitization of long, wideband chirped RF signals in the GHz band requires power hungry ADCs and produces large data sets. Here we present an optical scheme to perform multi-coset sampling of such signals with reduced power consumption and smaller data sets. In our scheme a repetitively pulsed femtosecond laser is dispersed to the interpulse time, the RF is modulated on the optical field, and the field is directed to a pair of wavelength-division demultiplexers (WDM). The channels of the WDM are attenuated with a pseudo-random sequence to form a coset pattern that repeats at the laser repetition rate. After a photodiode, the photocurrent is integrated for the duration of the dispersed optical pulse so that the coset pattern non-uniformly samples the RF signal. Since the laser repetition rate is uncorrelated with the RF, each coset provides an independent measurement of the RF. Experimental and numerical results show that 4 properties of the RF chirp pulse can be determined from the multiple coset samples: carrier frequency, chirp rate, start time, and pulse duration. Results are presented for a 20MHz chirp on a 13 microsecond pulse at a carrier of 2.473 GHz.

  1. Characteristics of a radial line slot antenna for 12 GHz band satellite TV reception

    NASA Astrophysics Data System (ADS)

    Ando, Makoto; Sakurai, Kimio; Goto, Naohisa

    1986-10-01

    Characteristics of a novel planar antenna which can radiate a circularly polarized pencil beam in x-band are presented for the application of receiving direct broadcast from a satellite. This antenna belongs to a class of slotted waveguide antennas and promising performances, especially its high efficiency, have already been predicted theoretically. The measured performance of a model antenna with a diameter of 0.6 m, is presented. Antenna gain of about 35 dBi and axial ratio of about 1 dB are realized at 12.2 GHz; the associated antenna efficiency of 57 percent is very high in comparison with that of the conventional microstrip antennas, in this range of gain.

  2. Experimental high gradient testing of a 17.1 GHz photonic band-gap accelerator structure

    NASA Astrophysics Data System (ADS)

    Munroe, Brian J.; Zhang, JieXi; Xu, Haoran; Shapiro, Michael A.; Temkin, Richard J.

    2016-03-01

    We report the design, fabrication, and high gradient testing of a 17.1 GHz photonic band-gap (PBG) accelerator structure. Photonic band-gap (PBG) structures are promising candidates for electron accelerators capable of high-gradient operation because they have the inherent damping of high order modes required to avoid beam breakup instabilities. The 17.1 GHz PBG structure tested was a single cell structure composed of a triangular array of round copper rods of radius 1.45 mm spaced by 8.05 mm. The test assembly consisted of the test PBG cell located between conventional (pillbox) input and output cells, with input power of up to 4 MW from a klystron supplied via a TM01 mode launcher. Breakdown at high gradient was observed by diagnostics including reflected power, downstream and upstream current monitors and visible light emission. The testing procedure was first benchmarked with a conventional disc-loaded waveguide structure, which reached a gradient of 87 MV /m at a breakdown probability of 1.19 ×10-1 per pulse per meter. The PBG structure was tested with 100 ns pulses at gradient levels of less than 90 MV /m in order to limit the surface temperature rise to 120 K. The PBG structure reached up to 89 MV /m at a breakdown probability of 1.09 ×10-1 per pulse per meter. These test results show that a PBG structure can simultaneously operate at high gradients and low breakdown probability, while also providing wakefield damping.

  3. The possibilities for mobile and fixed services up to the 20/30 GHz frequency bands

    NASA Astrophysics Data System (ADS)

    Hughes, Clifford D.; Feliciani, F.; Spiller, J.

    Satellite Communications and broadcasting is presently in a period of considerable change. In the fixed service there is strong competition from terrestrial fiber optic systems which have virtually arrested the growth of the traditional satellite market for long distance high capacity communications. The satellite has however made considerable progress in areas where it has unique advantages; for example, in point to multipoint (broadcasting), multipoint to point (data collection) and generally in small terminal system applications where flexibility of deployment coupled with ease of installation are of importance. In the mobile service, in addition to the already established geostationary systems, there are numerous proposals for HEO, MEO and LEO systems. There are also several new frequency allocations as a result of the WARC 92 to be taken into account. At one extreme there are researchers working on Ka band 20/30 GHz mobile systems and there are other groups who foresee no future above the L-band frequency allocations. Amongst all these inputs it is difficult to see the direction in which development activities both for satellites and for earth segment should be focused. However, as an aid to understanding, this paper seeks to find some underlying relationships and to clarify some of the variables.

  4. The possibilities for mobile and fixed services up to the 20/30 GHz frequency bands

    NASA Technical Reports Server (NTRS)

    Hughes, Clifford D.; Feliciani, F.; Spiller, J.

    1993-01-01

    Satellite Communications and broadcasting is presently in a period of considerable change. In the fixed service there is strong competition from terrestrial fiber optic systems which have virtually arrested the growth of the traditional satellite market for long distance high capacity communications. The satellite has however made considerable progress in areas where it has unique advantages; for example, in point to multipoint (broadcasting), multipoint to point (data collection) and generally in small terminal system applications where flexibility of deployment coupled with ease of installation are of importance. In the mobile service, in addition to the already established geostationary systems, there are numerous proposals for HEO, MEO and LEO systems. There are also several new frequency allocations as a result of the WARC 92 to be taken into account. At one extreme there are researchers working on Ka band 20/30 GHz mobile systems and there are other groups who foresee no future above the L-band frequency allocations. Amongst all these inputs it is difficult to see the direction in which development activities both for satellites and for earth segment should be focused. However, as an aid to understanding, this paper seeks to find some underlying relationships and to clarify some of the variables.

  5. 78 FR 9605 - Operation of Wireless Communications Services in the 2.3 GHz Band; Establishment of Rules and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-11

    ...In this document, the Commission affirms, modifies, and clarifies its actions in response to various petitions for reconsideration and/or clarification. The revised rules are intended to enable Wireless Communications Service (WCS) licensees to deploy broadband services in the 2305-2320 MHz and 2345-2360 MHz (2.3 GHz) WCS bands while continuing to protect Satellite Digital Audio Radio Service......

  6. 47 CFR 101.17 - Performance requirements for the 38.6-40.0 GHz frequency band.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Performance requirements for the 38.6-40.0 GHz frequency band. 101.17 Section 101.17 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Applications and Licenses General...

  7. 47 CFR 101.17 - Performance requirements for the 38.6-40.0 GHz frequency band.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Performance requirements for the 38.6-40.0 GHz frequency band. 101.17 Section 101.17 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Applications and Licenses General...

  8. 47 CFR 101.95 - Sunset provisions for licensees in the 18.30-19.30 GHz band.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Sunset provisions for licensees in the 18.30-19.30 GHz band. 101.95 Section 101.95 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Applications and Licenses Policies Governing Fixed Service Relocation from the...

  9. 47 CFR 101.95 - Sunset provisions for licensees in the 18.30-19.30 GHz band.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Sunset provisions for licensees in the 18.30-19.30 GHz band. 101.95 Section 101.95 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Applications and Licenses Policies Governing Fixed Service Relocation from the...

  10. 47 CFR 101.17 - Performance requirements for the 38.6-40.0 GHz frequency band.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Performance requirements for the 38.6-40.0 GHz frequency band. 101.17 Section 101.17 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Applications and Licenses General...

  11. 47 CFR 101.17 - Performance requirements for the 38.6-40.0 GHz frequency band.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Performance requirements for the 38.6-40.0 GHz frequency band. 101.17 Section 101.17 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Applications and Licenses General...

  12. 47 CFR 101.17 - Performance requirements for the 38.6-40.0 GHz frequency band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Performance requirements for the 38.6-40.0 GHz frequency band. 101.17 Section 101.17 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Applications and Licenses General...

  13. DUAL FREQUENCY RESONATOR FOR 1.2 GHZ EPR/16.2 MHZ NMR CO-IMAGING

    PubMed Central

    Petryakov, Sergey; Samouilov, Alexandre; Kesselring, Eric; Caia, George L.; Sun, Ziqi; Zweier, Jay L.

    2010-01-01

    The development of a dual frequency resonator that enables both EPR and proton NMR imaging within the same resonator, magnet and gradient system is described. A novel design allows the same resonator to perform both EPR and proton NMR operation without moving resonator cables or switches. The resonator is capable of working at frequencies of 16.18 MHz for proton NMR and 1.2 GHz for EPR and is optimized for isolated rat heart experiments, measuring 22 mm in inner diameter and 19 mm in length. In EPR mode, the resonator functions as a one loop two gap resonator, electrically coupled through a half wavelength inverter. In NMR mode, it functions a single turn coil. Using the same loop for both modalities maximizes filling factor at both frequencies. Placing the tuning and switching controls away from the resonator prevents any inadvertent movement that would cause errors of EPR and NMR co-imaging registration. The resonator enabled good quality EPR and proton MRI of isolated rat hearts with precise registration. PMID:20434379

  14. A Method to Transform Rainfall Rate to Rain Attenuation and Its Application to 21GHz Band Satellite Broadcasting

    NASA Astrophysics Data System (ADS)

    Nakazawa, Susumu; Tanaka, Shoji; Shogen, Kazuyoshi

    Satellite broadcasting in the 21-GHz band is expected to transmit large-capacity signals such as ultrahigh-definition TV. However, this band suffers from large amounts of rain attenuation. In this regard, we have been studying rain fading mitigation techniques, in which the radiation power is increased locally in the area of heavy rainfall. To design such a satellite broadcasting system, it is necessary to evaluate service availability when using the locally increased beam technique. The rain attenuation data should be derived from the rainfall rate data. We developed a method to transform rainfall rate into rain attenuation in the 21GHz band. Then, we performed a simulation that applied the method to the analysis of the service availability for an example phased array antenna configuration. The results confirmed the service availability increased with the locally increased beam technique.

  15. The ALMA Band 3 (84-116 GHz) receiver production plan

    NASA Astrophysics Data System (ADS)

    Yeung, Keith; Claude, Stéphane; Loop, David

    2008-07-01

    The NRC Herzberg Institute of Astrophysics (NRC-HIA) is currently responsible to contribute Band 3 (84-116 GHz) receivers to the international ALMA project - a partnership involving North America, Europe and, now, Asia. Not only are the technical requirements for these receivers far more stringent than those for any existing radio astronomy receivers operating at these frequencies, but the delivery schedule for these receivers is equally challenging. Since the Asian partnership joined the ALMA project in 2006, NRC-HIA has been asked to deliver an additional 11 cartridges, for a total of 73 units. Some of these new cartridges will be used for the ALMA Compact Array (ACA) and others as spares. Moreover, the project has also requested that these additional cartridges be delivered in the same time period as the original 62 units. To meet this requirement, production must increase from the existing rate of one unit every four weeks to one every two, taxing the existing production infrastructure at NRC-HIA. Additional test facilities and human resources must be planned to sustain the required production rate over the next several years. Industrial involvement is one of the important elements in our production plan. In order to supplement the existing human resources at NRC-HIA, we are planning to outsource a number of low-risk and labor-intensive tasks to industry. However, NRC-HIA will retain overall project management responsibility and will conduct all the cartridge integration and acceptance test activities in-house. This paper focuses on the resource estimation, planning and project management required to deliver the Band 3 receivers to the ALMA project on time and on budget.

  16. Low-loss and lightweight on-board 20 GHz-band pill-box-type directional filter

    NASA Astrophysics Data System (ADS)

    Ohtomo, I.; Kumazawa, H.

    1987-05-01

    An on-board channel multiplexer using pill-box-shaped TM(310) travelling-wave cavities with high unloaded Q-factor has been developed in the 20 GHz band. The measured branching loss of a three-cavity filter is 0.27 dB at a resonant frequency of 19.99 GHz. The weight of the filter made of thin-walled super-Invar is 71 g. Its size is 4.5 x 4.6 x 5.1 cm.

  17. Lewis Investigates Frequency Sharing Between Future NASA Space Systems and Local Multipoint Distribution Systems in the 27-GHz Band

    NASA Technical Reports Server (NTRS)

    1997-01-01

    At the request of the Federal Communications Commission (FCC), the NASA Lewis Research Center undertook an intensive study to examine the feasibility of frequency sharing between future NASA space services and proposed Local Multipoint Distribution Systems (LMDS) in the 25.25- to 27.5-GHz band. This follows NASA's earlier involvement in the FCC's 1994 Negotiated Rule Making Committee which studied frequency sharing between Ka-band Fixed Satellite Services and LMDS in the 27.5- to 29.5-GHz band. LMDS is a terrestrial, cellular, wireless communication service primarily intended to provide television distribution from hub stations located within relatively small cells to fixed subscriber receivers. Some proposed systems, however, also plan to offer interactive services via subscriber-to-hub transmissions. LMDS providers anticipate that their systems will be a cost-effective alternative to cable television systems, especially in urban areas. LMDS proponents have expressed an interest in using frequencies below 27.5 GHz. NASA, however, plans to operate three types of space systems below 27.5 GHz. The H, I, and J follow-on satellites for the Tracking and Data Relay Satellite System (TDRSS), which are planned for launch beginning in 1999, are designed to receive high-data-rate transmissions (up to 800 Mbps) from low-Earth orbiting "user" spacecraft in the 25.25- to 27.5-GHz band. In this case, the potential interference is the aggregate interference from LMDS transmitters (both hubs and subscribers) into the TDRSS tracking receive beams as they sweep over the Earth's surface while tracking lower altitude user spacecraft.

  18. 47 CFR 25.250 - Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands. 25.250 Section 25.250 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards §...

  19. 47 CFR 25.250 - Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Sharing between NGSO MSS Feeder links Earth Stations in the 19.3-19.7 GHz and 29.1-29.5 GHz Bands. 25.250 Section 25.250 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards §...

  20. Z45: A new 45-GHz band dual-polarization HEMT receiver for the NRO 45-m radio telescope

    NASA Astrophysics Data System (ADS)

    Nakamura, Fumitaka; Ogawa, Hideo; Yonekura, Yoshinori; Kimura, Kimihiko; Okada, Nozomi; Kozu, Minato; Hasegawa, Yutaka; Tokuda, Kazuki; Ochiai, Tetsu; Mizuno, Izumi; Dobashi, Kazuhito; Shimoikura, Tomomi; Kameno, Seiji; Taniguchi, Kotomi; Shinnaga, Hiroko; Takano, Shuro; Kawabe, Ryohei; Nakajima, Taku; Iono, Daisuke; Kuno, Nario; Onishi, Toshikazu; Momose, Munetake; Yamamoto, Satoshi

    2015-12-01

    We developed a dual-linear-polarization HEMT (High Electron Mobility Transistor) amplifier receiver system of the 45-GHz band (hereafter Z45), and installed it in the Nobeyama 45-m radio telescope. The receiver system is designed to conduct polarization observations by taking the cross-correlation of two linearly polarized components, from which we process full Stokes spectroscopy. We aim to measure the magnetic field strength through the Zeeman effect of the emission line of CCS (JN = 43-32) toward pre-protostellar cores. A linear-polarization receiver system has a smaller contribution of instrumental polarization components to the Stokes V spectra than that of the circular polarization system, so that it is easier to obtain the Stokes V spectra. The receiver has an RF frequency of 42-46 GHz and an intermediate frequency (IF) band of 4-8 GHz. The typical noise temperature is about 50 K, and the system noise temperature ranges from 100 to 150 K over the frequency of 42-46 GHz. The receiver system is connected to two spectrometers, SAM45 and PolariS. SAM45 is a highly flexible FX-type digital spectrometer with a finest frequency resolution of 3.81 kHz. PolariS is a newly developed digital spectrometer with a finest frequency resolution of 60 Hz, and which has a capability to process the full-Stokes spectroscopy. The half-power beam width (HPBW) was measured to be 37″ at 43 GHz. The main beam efficiency of the Gaussian main beam was derived to be 0.72 at 43 GHz. The SiO maser observations show that the beam pattern is reasonably round at about 10% of the peak intensity and the side-lobe level was less than 3% of the peak intensity. Finally, we present some examples of astronomical observations using Z45.

  1. W-band GaN MMIC PA with 257 mW output power at 86.5 GHz

    NASA Astrophysics Data System (ADS)

    Peng, Xu; Xubo, Song; Yuanjie, Lü; Yuangang, Wang; Shaobo, Dun; Jiayun, Yin; Yulong, Fang; Guodong, Gu; Zhihong, Feng; Shujun, Cai

    2015-08-01

    A three-stage W-band GaN monolithic microwave integrated circuit power amplifier (MMIC PA) is reported. In order to manage coupling effects between all the parts of the W-band MMIC, all matching and bias networks have been first optimized using circuit simulating software and then systematically simulated on 3D full-wave electromagnetic simulator. The fabricated MMIC PA achieves a 257 mW output power at 86.5 GHz in continuous-wave mode, with an associated power added efficiency of 5.4% and an associated power gain of 6.1 dB. The power density is 459 mW/mm. Moreover, the MMIC PA offers over 100 mW in the 83-90 GHz bandwidth. Those performances were measured at drain bias of 12 V. Project supported by the National Natural Science Foundation of China (No. 61306113).

  2. Sharing criteria and performance standards for the 11.7-12.2 GHz band in region 2

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Possible criteria for sharing between the broadcasting-satellite and the fixed-satellite services are considered for each of several parameters in three categories: system, space station, and earth station. Criteria for sharing between the two satellite services and the three terrestrial services to which the 12-GHz band is allocated are discussed separately, first for the case of the fixed and mobile services and then for the broadcasting service.

  3. Beyond G-band : a 235 GHz InP MMIC amplifier

    NASA Technical Reports Server (NTRS)

    Dawson, Douglas; Samoska, Lorene; Fung, A. K.; Lee, Karen; Lai, Richard; Grundbacher, Ronald; Liu, Po-Hsin; Raja, Rohit

    2005-01-01

    We present results on an InP monolithic millimeter- wave integrated circuit (MMIC) amplifier having 10-dB gain at 235 GHz. We designed this circuit and fabricated the chip in Northrop Grumman Space Technology's (NGST) 0.07- m InP high electron mobility transistor (HEMT) process. Using a WR3 (220-325 GHz) waveguide vector network analyzer system interfaced to waveguide wafer probes, we measured this chip on-wafer for -parameters. To our knowledge, this is the first time a WR3 waveguide on-wafer measurement system has been used to measure gain in a MMIC amplifier above 230 GHz.

  4. High Power SiGe X-Band (8-10 GHz) Heterojunction Bipolar Transistors and Amplifiers

    NASA Technical Reports Server (NTRS)

    Ma, Zhenqiang; Jiang, Ningyue; Ponchak, George E.; Alterovitz, Samuel A.

    2005-01-01

    Limited by increased parasitics and thermal effects as the device size becomes large, current commercial SiGe power HBTs are difficult to operate at X-band (8-12 GHz) with adequate power added efficiencies at high power levels. We found that, by changing the heterostructure and doping profile of SiGe HBTs, their power gain can be significantly improved without resorting to substantial lateral scaling. Furthermore, employing a common-base configuration with proper doping profile instead of a common-emitter configuration improves the power gain characteristics of SiGe HBTs, which thus permits these devices to be efficiently operated at X-band. In this paper, we report the results of SiGe power HBTs and MMIC power amplifiers operating at 8-10 GHz. At 10 GHz, 22.5 dBm (178 mW) RF output power with concurrent gain of 7.32 dB is measured at the peak power-added efficiency of 20.0% and the maximum RF output power of 24.0 dBm (250 mW) is achieved from a 20 emitter finger SiGe power HBT. Demonstration of single-stage X-band medium-power linear MMIC power amplifier is also realized at 8 GHz. Employing a 10-emitter finger SiGe HBT and on-chip input and output matching passive components, a linear gain of 9.7 dB, a maximum output power of 23.4 dBm and peak power added efficiency of 16% is achieved from the power amplifier. The MMIC exhibits very low distortion with third order intermodulation (IM) suppression C/I of -13 dBc at output power of 21.2 dBm and over 20dBm third order output intercept point (OIP3).

  5. Measurement and validation of GHz-band whole-body average SAR in a human volunteer using reverberation chamber

    NASA Astrophysics Data System (ADS)

    Wang, Jianqing; Suzuki, Tokio; Fujiwara, Osamu; Harima, Katsushige

    2012-12-01

    The World Health Organization’s (WHO) recommendation on the need for further research for radio-frequency dosimetry has promoted studies on the whole-body average-specific absorption rate (WBA-SAR) in various kinds of anatomical-based numerical models. For experimental validation of GHz-band WBA-SARs in a real human, however, there have not so far been any published papers, despite the fact that, in 1982, Hill measured WBA-SARs at frequencies less than 40 MHz in human volunteers using a TEM-cell exposure system. In this study, we provide a measurement technique with a reverberation chamber for validating numerical dosimetry results on GHz-band WBA-SARs in living humans. We measured WBA-SARs at 1, 1.5 and 2 GHz for a 22 year old male volunteer, with a height of 173 cm and a weight of 73 kg, in the reverberation chamber, and compared the results with the finite-difference time-domain (FDTD) simulation. The reverberation chamber was excited by using a signal generator through an amplifier with an output power of 30-40 mW, which produced inside the chamber with the volunteer an average electric field strength of 5 V m-1 equivalent to an average power spectral density of 6.6 μW cm-2. The WBA-SARs were obtained from the measured S11 and S21 together with the power density. On the other hand, the WBA-SARs have been calculated using the FDTD method for an adult male model with almost the same physique as that of the volunteer exposed to the electromagnetic field in the reverberation chamber. From the comparison between the measured and the calculated WBA-SARs, we could confirm that the measured GHz-band WBA-SARs approximately agree with the FDTD calculated results.

  6. A New Blind Pointing Model Improves Large Reflector Antennas Precision Pointing at Ka-Band (32 GHz)

    NASA Technical Reports Server (NTRS)

    Rochblatt, David J.

    2009-01-01

    The National Aeronautics and Space Administration (NASA), Jet Propulsion Laboratory (JPL)-Deep Space Network (DSN) subnet of 34-m Beam Waveguide (BWG) Antennas was recently upgraded with Ka-Band (32-GHz) frequency feeds for space research and communication. For normal telemetry tracking a Ka-Band monopulse system is used, which typically yields 1.6-mdeg mean radial error (MRE) pointing accuracy on the 34-m diameter antennas. However, for the monopulse to be able to acquire and lock, for special radio science applications where monopulse cannot be used, or as a back-up for the monopulse, high-precision open-loop blind pointing is required. This paper describes a new 4th order pointing model and calibration technique, which was developed and applied to the DSN 34-m BWG antennas yielding 1.8 to 3.0-mdeg MRE pointing accuracy and amplitude stability of 0.2 dB, at Ka-Band, and successfully used for the CASSINI spacecraft occultation experiment at Saturn and Titan. In addition, the new 4th order pointing model was used during a telemetry experiment at Ka-Band (32 GHz) utilizing the Mars Reconnaissance Orbiter (MRO) spacecraft while at a distance of 0.225 astronomical units (AU) from Earth and communicating with a DSN 34-m BWG antenna at a record high rate of 6-megabits per second (Mb/s).

  7. 47 CFR 15.255 - Operation within the band 57-64 GHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... power density of any emission, measured during the transmit interval, shall not exceed 9 μW/cm2, as measured 3 meters from the radiating structure, and the peak power density of any emission shall not exceed...-61.5 GHz, the average power density of any emission, measured during the transmit interval, shall...

  8. Polarization-adjustable dual-band absorption in GHz-band metamaterial, based-on no-smoking symbol

    NASA Astrophysics Data System (ADS)

    Yoo, Young Joon; Kim, Young Ju; Lee, YoungPak; Lee, Myung Whan; Lee, Tae Gyun; Kim, Min Woo; Park, Jae Hyun

    2015-11-01

    We propose three kinds of the perfect metamaterial absorbers based on the well-known no-smoking symbol, which can adjust the absorption according to the polarization of incident electromagnetic wave. By modifying no-smoking symbol, a resonance absorption peak at 6.75 GHz can be controlled. In addition, a split-ring structure and the no-smoking symbol also adjust the absorption. We also demonstrate the absorption mechanism for all the structures. These results can be used in controlling absorption by the electromagnetic-wave detector.

  9. Phase noise measurements of the 400-kW, 2.115-GHz (S-band) transmitter

    NASA Technical Reports Server (NTRS)

    Boss, P.; Hoppe, D.; Bhanji, A.

    1987-01-01

    The measurement theory is described and a test method to perform phase noise verification using off-the-shelf components and instruments is presented. The measurement technique described consists of a double-balanced mixer used as phase detector, followed by a low noise amplifier. An FFT spectrum analyzer is then used to view the modulation components. A simple calibration procedure is outlined that ensures accurate measurements. A block diagram of the configuration is presented as well as actual phase noise data from the 400 kW, 2.115 GHz (S-band) klystron transmitter.

  10. 1.2-17.6 GHz Ring-Oscillator-Based Phase-Locked Loop with Injection Locking in 65 nm Complementary Metal Oxide Semiconductor

    NASA Astrophysics Data System (ADS)

    Lee, Sang-yeop; Ito, Hiroyuki; Amakawa, Shuhei; Tanoi, Satoru; Ishihara, Noboru; Masu, Kazuya

    2012-02-01

    A wide-frequency-range phase-locked loop (PLL) with subharmonic injection locking is proposed. The PLL is equipped with a wide tunable ring-type voltage-controlled oscillator (ring VCO), frequency dividers, and a doubler in order to the widen injection-locked tuning range (ILTR). In addition, high-frequency injection signals are used to improve phase noise, which is supposed to be generated by a reference PLL. The proposed circuit is fabricated by using a 65 nm Si complementary metal oxide semiconductor (CMOS) process. The measured frequency tuning range is from 1.2 to 17.6 GHz with a frequency doubler and dividers. The phase noise at 14.4 GHz (=32×450 MHz) with injection locking was -109 dBc/Hz, which shows a 21-dB reduction compared with that in the case without injection locking.

  11. Estimation of Transmitting Power to Compensate for Rain Attenuation for a Broadcasting Satellite System in the 21-GHz Band

    NASA Astrophysics Data System (ADS)

    Minematsu, Fumiaki; Tanaka, Shoji; Nakagawa, Hitoshi; Kawaguchi, Yutaka

    2002-01-01

    1. INTRODUCTION Rain attenuation in the 21-GHz band is much larger than that in the conventionally used 12-GHz band and the rain attenuation causes more serious program interruptions compared with that in the 12-GHz band. We are now studying an advanced broadcasting satellite in the 21-GHz band that enables adaptive compensation for heavy rain area by boosted beams using an on-board phased-array-transmitting antenna. To know the scale of this satellite system, it is important to estimate transmitting power needed to compensate for rain attenuation. Rain attenuation has so close association with rainfall that it is possible to estimate rain attenuation by measured rainfall. Japan meteorological agency is measuring 1-hour rainfalls for about 1300 locations in Japan. In this study, 1-hour rainfall data accumulated at more than 1000 locations over a period of 20 years were used statistically to grasp rainfall distribution throughout Japan and the transmitting power for compensation was estimated by use of these data. 2. CALCULATION MODEL FOR TRANSMITTING POWER ESTIMATION Assumed rain attenuation compensation area for Japanese archipelago was divided into 112 square areas. A size of each square was 0.1 degree in terms of azimuth and elevation angle for the beam direction of satellite transmitting antenna. For calculation, the link margin of 3.5 dB for clear sky was given to the area where 1-hour rainfall not larger than 3 mm was detected. For other square areas where 1-hour rainfall larger than 3 mm was detected, the link margin of 12 dB was given. The former link margin corresponds to the service availability of 99 % and the latter does to that of 99.9 % in an average year in Tokyo. A total system efficiency included radiation efficiency of the transmitting antenna of 1.0 was assumed. As modulation scheme, trellis coded 8-PSK (TC8PSK) was assumed. The required reception CN ratio for TC8PSK is 10.7 dB. As to TC8PSK, the baud rate of 57.72 Mbaud gives more than 100 Mbps

  12. A high-power communications technology satellite for the 12 and 14 GHz bands.

    NASA Technical Reports Server (NTRS)

    Franklin, C. A.; Davison, E. H.

    1972-01-01

    Description of the mission, subsystems and communication capabilities of a joint Communications Technology Satellite (CTS) scheduled for launch in 1975 by the Canadian Department of Communications in cooperation with NASA. The principal objectives of the mission are TV transmission at 12 GHz to low-cost ground terminals, up-link TV transmission at 14 GHz transportable terminals, and flight tests of spacecraft subsystems and components for future communications satellites. The major advanced spacecraft subsystems are a novel superefficiency TWT design, a 0.4 mlb Mercury Bombardment ion engine for north-south station keeping, a 3-axis stabilization system to maintain a high antenna boresight pointing accuracy, a liquid metal slip ring experiment, and a lightweight extendible solar array with an initial power output greater than 1 kW.

  13. Beam Measurement of 11.424 GHz X-Band Linac for Compton Scattering X-ray Source

    SciTech Connect

    Natsui, Takuya; Mori, Azusa; Masuda, Hirotoshi; Uesaka, Mitsuru; Sakamoto, Fumito

    2010-11-04

    An inverse Compton scattering X-ray source for medical applications, consisting of an X-band (11.424 GHz) linac and Q-switched Nd:YAG laser, is currently being developed at the University of Tokyo. This system uses an X-band 3.5-cell thermionic cathode RF gun for electron beam generation. We can obtain a multi-bunch electron beam with this gun. The beam is accelerated to 30 MeV by a traveling-wave accelerating tube. So far, we have verified stable beam generation (around 2.3 MeV) by using the newly designed RF gun and we have succeeded in beam transportation to a beam dump.

  14. Potential Interference to the Deep Space Network Stations in Spain from NPOESS in the 25.5- to 27.0-GHz Band

    NASA Astrophysics Data System (ADS)

    Tsou, H.

    2008-08-01

    A new Instituto Nacional de Tecnica Aeroespacial (INTA) station, located about 70 km east of the Deep Space Network (DSN) Madrid complex (Robledo), is planned to support National Polar-orbiting Operational Environmental Satellite System (NPOESS) satellites. The 26.7-GHz NPOESS Ka-band downlink to this proposed station can potentially interfere with the DSN Madrid station that may support the future lunar and Sun-Earth Lagrange point missions operating in the 25.5- to 27.0-GHz band. A preliminary compatibility analysis has been conducted to assess the potential impact to the DSN Madrid complex from the NPOESS Ka-band downlink to the planned INTA station.

  15. Optical-network-connected multi-channel 96-GHz-band distributed radar system

    NASA Astrophysics Data System (ADS)

    Kanno, Atsushi; Kuri, Toshiaki; Kawanishi, Tetsuya

    2015-05-01

    The millimeter-wave (MMW) radar is a promising candidate for high-precision imaging because of its short wavelength and broad range of available bandwidths. In particular in the frequency range of 92-100 GHz, which is regulated for radiolocation, an atmospheric attenuation coefficient less than 1 dB/km limits the imaging range. Therefore, a combination of MMW radar and distributed antenna system directly connected to optical fiber networks can realize both high-precision imaging and large-area surveillance. In this paper, we demonstrate a multi-channel MMW frequency-modulated continuous-wave distributed radar system connected to an analog radio-over-fiber network.

  16. Assessment of corneal hydration sensing in the terahertz band: in vivo results at 100 GHz

    NASA Astrophysics Data System (ADS)

    Bennett, David; Taylor, Zachary; Tewari, Pria; Sung, Sijun; Maccabi, Ashkan; Singh, Rahul; Culjat, Martin; Grundfest, Warren; Hubschman, Jean-Pierre; Brown, Elliott

    2012-09-01

    Terahertz corneal hydration sensing has shown promise in ophthalmology applications and was recently shown to be capable of detecting water concentration changes of about two parts in a thousand in ex vivo corneal tissues. This technology may be effective in patient monitoring during refractive surgery and for early diagnosis and treatment monitoring in diseases of the cornea. In this work, Fuchs dystrophy, cornea transplant rejection, and keratoconus are discussed, and a hydration sensitivity of about one part in a hundred is predicted to be needed to successfully distinguish between diseased and healthy tissues in these applications. Stratified models of corneal tissue reflectivity are developed and validated using ex vivo spectroscopy of harvested porcine corneas that are hydrated using polyethylene glycol solutions. Simulation of the cornea's depth-dependent hydration profile, from 0.01 to 100 THz, identifies a peak in intrinsic reflectivity contrast for sensing at 100 GHz. A 100 GHz hydration sensing system is evaluated alongside the current standard ultrasound pachymetry technique to measure corneal hydration in vivo in four rabbits. A hydration sensitivity, of three parts per thousand or better, was measured in all four rabbits under study. This work presents the first in vivo demonstration of remote corneal hydration sensing.

  17. 47 CFR 15.255 - Operation within the band 57-64 GHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... band, as measured with a 100 kHz resolution bandwidth spectrum analyzer. The center frequency must be... identification feature and must specify a method whereby interested parties can obtain sufficient information,...

  18. Optical Band Gap Study Of Nanocrystalline NiCr0.8Fe1.2O4 Ferrite

    NASA Astrophysics Data System (ADS)

    Prasad, Arun S.; Dolia, S. N.; Dhawan, M. S.; Predeep, P.

    2008-04-01

    Optical energy band gap of nanocrystalline NiCr0.8Fe1.2O4 ferrite have been studied. The nanocrystalline NiCr0.8Fe1.2O4 ferrite have been synthesized using sol-gel technique. X-ray diffraction pattern confirms the formation of spinel structure in single phase and the average particle size is 4 nm. The energy band gap measurements of nanocrystalline NiCr0.8Fe1.2O4 ferrite in pellet form have been carried out by absorption spectra using double beam spectrophotometer. A pellet of nanoparticle ferrite was made under a load of 10 tons. From the analysis of absorption spectra, nanocrystalline NiCr0.8Fe1.2O4 ferrite have been found to have energy band gap of 3.2 eV at room temperature.

  19. 47 CFR 15.252 - Operation of wideband vehicular radar systems within the bands 16.2-17.7 GHz and 23.12-29.0 GHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... fundamental frequency following the provisions of § 15.31(m). (3) For systems operating in the 23.12-29.0 GHz... are used only for back-up assistance and that operate only when the vehicle is engaged in reverse. (1... emission appear shall be greater than 24.075 GHz. (4) These devices shall operate only when the vehicle...

  20. Heterodyne laser-Doppler vibrometer with a slow-shear-mode Bragg cell for vibration measurements up to 1.2 GHz

    NASA Astrophysics Data System (ADS)

    Rembe, Christian; Boedecker, Sebastian; Dräbenstedt, Alexander; Pudewills, Fred; Siegmund, Georg

    2008-06-01

    Several new applications for optical ultra-high frequency (UHF) measurements have been evolved during the last decade by advancements in ultra-sonic filters and actuators as well as by the progress in micro- and nanotechnology. These new applications require new testing methods. Laser-based, non-influencing optical testing is the best choice. In this paper we present a laser-Doppler vibrometer for vibration measurements at frequencies up to 1.2 GHz. The frequency-shifter in the heterodyne interferometer is a slow-shear-mode Bragg cell. The light source in the interferometer is a green DPSS (diode pumped solid state) laser. At this wavelength the highest possible frequency shift between zero and first diffraction order is a few MHz above 300 MHz for a slow shear-mode Bragg cell and, therefore, the highest possible bandwidth of the laser-Doppler vibrometer should usually be around 300 MHz. A new optical arrangement and a novel signal processing of the digitized photo-detector signal is employed to expand the bandwidth to 1.2 GHz. We describe the utilized techniques and present the characterization of the new ultra-high-frequency (UHF) vibrometer. An example measurement on a surface acoustic wave (SAW) resonator oscillating at 262 MHz is also demonstrated. The light-power of the measurement beam can be switched on rapidly by a trigger signal to avoid thermal influences on the sample.

  1. A Balloon-borne Limb-Emission Sounder at 650-GHz band for Stratospheric observations

    NASA Astrophysics Data System (ADS)

    Irimajiri, Yoshihisa; Ochiai, Satoshi

    We have developed a Balloon-borne Superconducting Submillimeter-Wave Limb-Emission Sounder (BSMILES) to observe stratospheric minor constituents like ozone, HCl etc. BSMILES carries a 300mm-diameter offset parabolic antenna, a 650-GHz heterodyne superconducting (SIS) low-noise receiver, and an acousto-optical spectrometer (AOS) with the bandwidth of 1GHz and the resolution of 1MHz. Gondola size is 1.35 m x 1.35 m x 1.26 m. Total weight is about 500 kg. Limb observations are made by scanning the antenna beam of about 0.12 degrees (FWHM) in vertical direction. A calibrated hot load (CHL) and elevation angle of 50 degrees are ob-served after each scan for calibration. The DSB system noise temperature of the SIS receiver is less than 460 K at 624-639 GHz with a best value of 330 K that is 11 times as large as the quantum limit. Data acquisition and antenna control are made by on-board PCs. Observed data are recorded to PC card with 2 GB capacity to collect after the observations from the sea, and HK data are transmitted to the ground. Gondola attitude is measured by three-axis fiber-optical gyroscope with accuracy less than 0.01 degrees, three-axis accelerometer, and a two-axis geoaspect sensor. Electric power is supplied by lithium batteries. Total power con-sumption is about 150W. Almost all systems are put in pressurized vessels for waterproofing, heat dissipation, and noise shield, etc. BSMILES was launched from Sanriku Balloon Center of Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), at the east coast of Japan, in the summer of 2003, 2004, and 2006. The gondola was carried to an altitude of 35 km by a balloon of 100,000 m3 in volume and the observations were made for 1.5 hours in 2004. All systems operated normally by keeping their temperature within the limit of operation by keeping gondola warm with styrene foam. After the observations, the gondola was dropped and splashed on the Pacific Ocean by a parachute and

  2. AN INTERFEROMETRIC SPECTRAL-LINE SURVEY OF IRC+10216 IN THE 345 GHz BAND

    SciTech Connect

    Patel, Nimesh A.; Young, Ken H.; Gottlieb, Carl A.; Thaddeus, Patrick; Wilson, Robert W.; Reid, Mark J.; McCarthy, Michael C.; Keto, Eric; Menten, Karl M.; Cernicharo, Jose; He Jinhua; Bruenken, Sandra; Trung, Dinh-V.

    2011-03-15

    We report a spectral-line survey of the extreme carbon star IRC+10216 carried out between 293.9 and 354.8 GHz with the Submillimeter Array. A total of 442 lines were detected, more than 200 for the first time; 149 are unassigned. Maps at an angular resolution of {approx}3'' were obtained for each line. A substantial new population of narrow lines with an expansion velocity of {approx}4 km s{sup -1} (i.e., {approx}30% of the terminal velocity) was detected. Most of these are attributed to rotational transitions within vibrationally excited states, emitted from energy levels above the v = 0, J = 0 ground state with excitation energy of 1000-3000 K. Emission from these lines appears to be centered on the star with an angular extent of <1''. We use multiple transitions detected in several molecules to derive physical conditions in this inner envelope of IRC+10216.

  3. The Potential for a Ka-band (32 GHz) worldwide VLBI network

    NASA Astrophysics Data System (ADS)

    Jacobs, Christopher S.; Bach, U.; Colomer, F.; García-Miró, C.; Gómez-González, J.; Gulyaev, S.; Horiuchi, S.; Ichikawa, R.; Kraus, A.; Kronschnabl, G.; López-Fernández, J. A.; Lovell, J.; Majid, W.; Natusch, T.; Neidhardt, A.; Philips, C.; Porcas, R.; Romero-Wolf, A.; Saldana, L.; Schreiber, U.; Sotuela, I.; Takeuchi, H.; Trinh, J.; Tzioumis, A.; de Vincente, P.; Zharov, V.

    2012-12-01

    Ka-band VLBI capability now exists, is under development or is being considered at 22 sites around the world. Thus, there is now an opportunity to create a worldwide Ka-band VLBI network. This paper will examine the potential for a cooperative network capable of high resolution imaging and astrometry. Initial fringe tests on a few individual baselines have been successful and more tests are planned. With baselines approaching a Giga-lambda, a Ka-band network would be able to probe source structure at the nano-radian (200 μas) level and thus gain insight into astrophysics of the most compact regions of emission in active galactic nuclei.

  4. Celestial Reference Frame at X/KA-Band (8.4/32 GHz) for Deep Space Navigation

    NASA Astrophysics Data System (ADS)

    Jacobs, Christopher S.; Clark, J. E.; García-Miró, C.; Horiuchi, S.; Romero-Wolf, A.; Snedeker, L. G.; Sotuela, I.

    2012-10-01

    Deep space tracking and navigation are done in a quasi-inertial reference frame based upon the angular positions of distant active galactic nuclei (AGN). These objects, which are found at extreme distances characterized by median redshifts of z = 1, are ideal for reference frame definition because they exhibit no measurable parallax or proper motion. They are thought to be powered by super massive black holes whose gravitational energy drives galactic sized relativistic jets. These jets produce synchrotron emissions which are detectable by modern radio techniques such as Very Long baseline Interferometry (VLBI). We have constructed a reference frame based on sixty seven X/Ka-band (8.4/32 GHz) VLBI observing sessions (2005 to present), each of ∼24 hours duration, using the intercontinental baselines of NASA's Deep Space Network (DSN): Goldstone, California to Madrid, Spain and Canberra, Australia. We detected 482 sources covering the full 24 hours of right ascension and declinations down to -45 deg. Comparison of 460 X/Ka sources in common with the international standard ICRF2 at S/X-band (2.3/8.4 GHz) shows wRMS agreement of 180 μas in RA cos(dec) and 270 μas in Dec. There is evidence for systematic errors at the 100 μas level. Known errors include limited SNR, lack of phase calibration, troposphere mismodelling, and limited southern geometry. Compared to S/X-band frames (e.g. ICRF2 (Ma et al, 2009)), X/Ka-band allows access to more compact source morphology and reduced core shift. Both these improvements allow for a more well-defined and stable reference frame at X/Ka-band. In the next decade, the optically-based Gaia mission (Lindegren, 2008) may produce a frame with competitive precision. By accurately registering radio frames with Gaia, we could study wavelength dependent systematic errors. A simulated frame tie between our X/Ka radio frame and the Gaia optical frame predicts a frame tie precision of 10-15 μas (1-σ, per 3-D rotation component) with

  5. Uncertainty of GHz-band Whole-body Average SARs in Infants based on their Kaup Indices

    NASA Astrophysics Data System (ADS)

    Miwa, Hironobu; Hirata, Akimasa; Fujiwara, Osamu; Nagaoka, Tomoaki; Watanabe, Soichi

    We previously showed that a strong correlation exists between the absorption cross section and the body surface area of a human for 0.3-2GHz far field exposure, and proposed a formula for estimating whole-body-average specific absorption rates (WBA-SARs) in terms of height and weight. In this study, to evaluate variability in the WBA-SARs in infants based on their physique, we derived a new formula including Kaup indices of infants, which are being used to check their growth, and thereby estimated the WBA-SARs in infants with respect to their age from 0 month to three years. As a result, we found that under the same height/weight, the smaller the Kaup indices are, the larger the WBA-SARs become, and that the variability in the WBA-SARs is around 15% at the same age. To validate these findings, using the FDTD method, we simulated the GHz-band WBA-SARs in numerical human models corresponding to infants with age of 0, 1, 3, 6 and 9 months, which were obtained by scaling down the anatomically based Japanese three-year child model developed by NICT (National Institute of Information and Communications Technology). Results show that the FDTD-simulated WBA-SARs are smaller by 20% compared to those estimated for infants having the median height and the Kaup index of 0.5 percentiles, which provide conservative WBA-SARs.

  6. Sub-GHz-resolution C-band Nyquist-filtering interleaver on a high-index-contrast photonic integrated circuit.

    PubMed

    Zhuang, Leimeng; Zhu, Chen; Corcoran, Bill; Burla, Maurizio; Roeloffzen, Chris G H; Leinse, Arne; Schröder, Jochen; Lowery, Arthur J

    2016-03-21

    Modern optical communications rely on high-resolution, high-bandwidth filtering to maximize the data-carrying capacity of fiber-optic networks. Such filtering typically requires high-speed, power-hungry digital processes in the electrical domain. Passive optical filters currently provide high bandwidths with low power consumption, but at the expense of resolution. Here, we present a passive filter chip that functions as an optical Nyquist-filtering interleaver featuring sub-GHz resolution and a near-rectangular passband with 8% roll-off. This performance is highly promising for high-spectral-efficiency Nyquist wavelength division multiplexed (N-WDM) optical super-channels. The chip provides a simple two-ring-resonator-assisted Mach-Zehnder interferometer, which has a sub-cm2 footprint owing to the high-index-contrast Si3N4/SiO2 waveguide, while manifests low wavelength-dependency enabling C-band (> 4 THz) coverage with more than 160 effective free spectral ranges of 25 GHz. This device is anticipated to be a critical building block for spectrally-efficient, chip-scale transceivers and ROADMs for N-WDM super-channels in next-generation optical communication networks. PMID:27136769

  7. Wireless Channel Characterization: Modeling the 5 GHz Microwave Landing System Extension Band for Future Airport Surface Communications

    NASA Technical Reports Server (NTRS)

    Matolak, D. W.; Apaza, Rafael; Foore, Lawrence R.

    2006-01-01

    We describe a recently completed wideband wireless channel characterization project for the 5 GHz Microwave Landing System (MLS) extension band, for airport surface areas. This work included mobile measurements at large and small airports, and fixed point-to-point measurements. Mobile measurements were made via transmission from the air traffic control tower (ATCT), or from an airport field site (AFS), to a receiving ground vehicle on the airport surface. The point-to-point measurements were between ATCT and AFSs. Detailed statistical channel models were developed from all these measurements. Measured quantities include propagation path loss and power delay profiles, from which we obtain delay spreads, frequency domain correlation (coherence bandwidths), fading amplitude statistics, and channel parameter correlations. In this paper we review the project motivation, measurement coordination, and illustrate measurement results. Example channel modeling results for several propagation conditions are also provided, highlighting new findings.

  8. A Multi-Feed Receiver in the 18 to 26.5 GHz Band for Radio Astronomy

    NASA Astrophysics Data System (ADS)

    Orfei, A.; Carbonaro, L.; Cattani, A.; Cremonini, A.; Cresci, L.; Fiocchi, F.; Maccaferri, A.; Maccaferri, G.; Mariotti, S.; Monari, J.; Morsiani, M.; Natale, V.; Nesti, R.; Panella, D.; Poloni, M.; Roda, J.; Scalambra, A.; Tofani, G.

    2010-08-01

    A large-bandwidth, state-of-the-art multi-feed receiver has been constructed to be used on the new 64 m Sardinia Radio Telescope (SRT) (http://www.srt.inaf.itl), an antenna aiming to work from 300 MHz to 100 GHz with an almost continuous frequency coverage. The goal of this new receiver is to speed up the survey of the sky with high sensitivity in a frequency band that is very interesting to radio astronomers. In the meantime, the antenna erection has been finalized, and the receiver has been mounted on the Medicina 32 m antenna to be tested (http://www.med.ira.inaf.itl). We present a complete description of the system, including a dedicated backend, and the results of the tests.

  9. Ocean Surface Emissivity at L-band (1.4 GHz): The Dependence on Salinity and Roughness

    NASA Technical Reports Server (NTRS)

    LeVine, D. M.; Lang, R.; Wentz, F.; Messiner, T.

    2012-01-01

    A characterization of the emissivity of sea water at L-band is important for the remote sensing of sea surface salinity. Measurements of salinity are currently being made in the radio astronomy band at 1.413 GHz by ESA's Soil Moisture and Ocean Salinity (SMOS) mission and NASA's Aquarius instrument aboard the Aquarius/SAC-D observatory. The goal of both missions is accuracy on the order of 0.1 psu. This requires accurate knowledge of the dielectric constant of sea water as a function of salinity and temperature and also the effect of waves (roughness). The former determines the emissivity of an ideal (i.e. flat) surface and the later is the major source of error from predictions based on a flat surface. These two aspects of the problem of characterizing the emissivity are being addressed in the context of the Aquarius mission. First, laboratory measurements are being made of the dielectric constant of sea water. This is being done at the George Washington University using a resonant cavity. In this technique, sea water of known salinity and temperature is fed into the cavity along its axis through a narrow tube. The sea water changes the resonant frequency and Q of the cavity which, if the sample is small enough, can be related to the dielectric constant of the sample. An extensive set of measurements have been conducted at 1.413 GHz to develop a model for the real and imaginary part of the dielectric constant as a function of salinity and temperature. The results are compared to the predictions of models based on parameterization of the Debye resonance of the water molecule. The models and measurements are close; however, the differences are significant for remote sensing of salinity. This is especially true at low temperatures where the sensitivity to salinity is lowest.

  10. FANATIC: An SIS Radiometer for Radio Astronomy in the 660-690 GHz Band

    NASA Astrophysics Data System (ADS)

    Harris, A. I.; Schuster, K.-F.; Gundlach, K.-H.; Plathner, B.

    1994-05-01

    FANATIC is a compact radiometer optimized for radio astronomy from about 660 to 690 GHz (455-435 micron). We observed a large number of molecular and atomic spectral lines from galactic and extragalactic sources during FANATIC's first run on the James Clerk Maxwell Telescope in early March 1994. Double sideband receiver temperatures during observations were about 800 K (25 hv/k). The heart of the receiver is a two-junction Nb/AlOx/Nb SIS array fed by a sandwiched V-Antenna. The junction array and antenna are fabricated together at IRAM's Grenoble SIS laboratory. Each junction has a normal resistance of Rn~10 ohm, an area of ~2 um^2 , an individual radial stub circuit to resonate the capacitance, and a 1/4-wavelength transformer to match to the antenna. The solid-state local oscillator is a mm-wave Gunn oscillator followed by a doubler and tripler. The LO diplexer is a Martin-Puplett interferometer, which insures that there is always abundant LO power for operation and speedy tuning. The receiver and telescope coupling optics, LO, dewar, and calibration system fit on an 0.6 x 0.8 m optical breadboard.

  11. An Interferometric Spectral Line and Imaging Survey of VY Canis Majoris in the 345 GHz Band

    NASA Astrophysics Data System (ADS)

    Kamiński, T.; Gottlieb, C. A.; Young, K. H.; Menten, K. M.; Patel, N. A.

    2013-12-01

    A spectral line survey of the oxygen-rich red supergiant VY Canis Majoris was made between 279 and 355 GHz with the Submillimeter Array (SMA). Two hundred twenty-three spectral features from 19 molecules (not counting isotopic species of some of them) were observed, including the rotational spectra of TiO, TiO2, and AlCl for the first time in this source. The parameters and an atlas of all spectral features are presented. Observations of each line with a synthesized beam of ~0.''9, reveal the complex kinematics and morphology of the nebula surrounding VY CMa. Many of the molecules are observed in high-lying rotational levels or in excited vibrational levels. From these, it was established that the main source of the submillimeter-wave continuum (dust) and the high-excitation molecular gas (the star) are separated by about 0.''15. Apparent coincidences between the molecular gas observed with the SMA, and some of the arcs and knots observed at infrared wavelengths and in the optical scattered light by the Hubble Space Telescope are identified. The observations presented here provide important constraints on the molecular chemistry in oxygen-dominated circumstellar environments and a deeper picture of the complex circumstellar environment of VY CMa.

  12. Implication of a color multibeam communications satellite in the 30/20 GHz bands

    NASA Technical Reports Server (NTRS)

    Hoffman, M.

    1982-01-01

    In order to meet the need for increased communications capacity, NASA is conducting a program to develop technology and systems for a 30/20 GHz multibeam domestic U.S. satellite. One way to provide the required national interconnectivity is to permute and time share connections among the involved areas by means of a satellite-borne multiport microwave switch with a Time-Division Multiple Access (TDMA) system. In this connection, the question was analyzed whether a practical satellite message routing system can be developed using FDMA techniques. The total traffic (model A) was derived and used as an input specification for the satellite-routed FDMA study. Attention is given to beam isolations, color and regional systems, the level of service, and the color FDMA satellite. It is concluded that the FDMA system considered can handle substantially all the Customer Premises Service (CPS) and Trunking (TR) traffic in Model A. The (color) scheme completely satisfies the CPS and TR requirements of 23 cities.

  13. Low Noise Amplifiers for 140 Ghz Wide-Band Cryogenic Receivers

    NASA Technical Reports Server (NTRS)

    Larkoski, Patricia V.; Kangaslahti, Pekka; Samoska, Lorene; Lai, Richard; Sarkozy, Stephen

    2013-01-01

    We report S-parameter and noise measurements for three different Indium Phosphide 35-nanometer-gate-length High Electron Mobility Transistor (HEMT) Low Noise Amplifier (LNA) designs operating in the frequency range centered on 140 gigahertz. When packaged in a Waveguide Rectangular-6.1 waveguide housing, the LNAs have an average measured noise figure of 3.0 decibels - 3.6 decibels over the 122-170 gigahertz band. One LNA was cooled to 20 degrees Kelvin and a record low noise temperature of 46 Kelvin, or 0.64 decibels noise figure, was measured at 152 gigahertz. These amplifiers can be used to develop receivers for instruments that operate in the 130-170 gigahertz atmospheric window, which is an important frequency band for ground-based astronomy and millimeter-wave imaging applications.

  14. Satellite and terrestrial narrow-band propagation measurements at 2.05 GHz

    NASA Technical Reports Server (NTRS)

    Vaisnys, Arv; Vogel, Wolf

    1995-01-01

    A series of satellite and terrestrial propagation measurements were conducted on 15 and 16 Dec. 1994 in the vicinity of the Jet Propulsion Laboratory (JPL), Pasadena, California, in support of the VOA/JPL DBS-Radio Program. The reason for including terrestrial measurements was the possible use of terrestrial boosters to improve reception in some satellite digital audio broadcasting system service areas. The signal sources used were the NASA TDRS satellite located at 171 degrees West and a terrestrial transmitter located on a high point on JPL property. Both signals were unmodulated carriers near 2.05 GHz, spaced a few kHz apart so that both could be received simultaneously by a single receiver. An unmodulated signal was used in order to maximize the dynamic range of the signal strength measurement. A range of greater than 35 dB was achieved with the satellite signal, and over 50 dB was achieved with the terrestrial signal measurements. Three test courses were used to conduct the measurements: (1) a 33 km round trip drive from JPL through Pasadena was used to remeasure the propagation of the satellite signal over the path previously used in DBS-Radio experiments in mid 1994. A shortened portion of this test course, approximately 20 km, was used to measure the satellite and terrestrial signals simultaneously; (2) a 9 km round trip drive through JPL property, going behind buildings and other obstacles, was used to measure the satellite and terrestrial signals simultaneously; and (3) a path through one of the buildings at JPL, hand carrying the receiver, was also used to measure the satellite and terrestrial signals simultaneously.

  15. A Real-Time Microwave Camera at K-Band (24 GHz)

    NASA Technical Reports Server (NTRS)

    Ghasr, M. T.; Abou-Khousa, M.; Baumgartner, M. A.; Zoughi, R.

    2009-01-01

    Nondestructive testing (NDT) community has been moving towards effective and robust inspection systems that can provide real-time information about materials, geometrical, structural and mechanical characteristics of composite materials/structures. Moreover, in many applications it is desired to have an image of the structure, after which the information contained in the image is correlated to the above characteristics. Microwave signals penetrate inside of dielectric composite structures and their interaction with the interior of the structure renders critical information for NDT purposes. Subsequently, this information (i.e., magnitude and phase or reflected signal) may be used to produce an image of the interior of the structure revealing potential flaws or anomalies. Image processing and reconstruction techniques may also be incorporated to produce high-resolution images (i.e., synthetic-aperture, back-propagation, etc.). There are several different approaches for designing areal-time microwave camera system. One approach is based on modulated scatterer technique (MST), which is used to tag scattered electric field in a discrete two-dimensional (2D) spatial domain (e.g. a retina) resulting in the 2D magnitude and phase distribution of the scattered electric field which is required for producing an image of a material or structure under inspection. The ability to rapidly modulate resonant slot antennas in such a retina along with using receivers with fast responses provide for real-time image production capability. Design issue and criteria become more challenging at higher frequencies and for a relatively large retina size. This paper presents the basic design and challenges for a microwave camera with a retina size of 6" by 6" operating at a frequency of 24 GHz.

  16. A Monolithic Sub-sampling PLL based 6-18 GHz Frequency Synthesizer for C, X, Ku Band Communication

    NASA Astrophysics Data System (ADS)

    Zhou, Hanchao; Zhu, Ning; LI, Wei; Zhou, Zibo; Li, Ning; Ren, Junyan

    A monolithic frequency synthesizer with wide tuning range, low phase noise and spurs was realized in 0.13 μm CMOS technology. It consists of an analog PLL, a harmonic-rejection mixer and injection-locked frequency doublers to cover the whole 6-18 GHz frequency range. To achieve a low phase noise performance, a sub-sampling PLL with non-dividers was employed. The synthesizer can achieve phase noise -113.7 dBc/Hz@100 kHz in the best case and the reference spur is below -60 dBc. The core of the synthesizer consumes about 110 mA*1.2 V.

  17. Response of L-alanine and 2-methylalanine minidosimeters for K-Band (24 GHz) EPR dosimetry

    NASA Astrophysics Data System (ADS)

    Chen, F.; Graeff, C. F. O.; Baffa, O.

    2007-11-01

    Minidosimeters of L-alanine and 2-methylalanine (2MA) were prepared and tested as potential candidates for small radiation field dosimetry. To quantify the free radicals created by radiation a K-Band (24 GHz) EPR spectrometer was used. X-rays provided by a 6 MV clinical linear accelerator were used to irradiate the minidosimeters in the dose range of 0.5-30 Gy. The dose-response curves for both radiation sensitive materials displayed a good linear behavior in the dose range indicated with 2MA being more radiation sensitive than L-alanine. Moreover, 2MA showed a smaller LLD (lower limit detection) value. The proposed system minidosimeter/K-Band spectrometer was able to detect 10 Gy EPR spectra with good signal-to-noise ratio (S/N). The overall uncertainty indicates that this system shows a good performance for the detection of dose values of 20 Gy and above, which are dose values typically used in radiosurgery treatments.

  18. Frequency sharing between passive sensors and aeronautical radionavigation systems employing ground transponders in the band 4.2 - 4.4 GHz

    NASA Technical Reports Server (NTRS)

    Degroot, N. F.

    1982-01-01

    The 4.2 to 4.4 GHz band is reserved for radio altimeters aboard aircraft and for associated transponders on the ground. A radar altimeter system which utilizes associated ground transponders is described and the feasibility of co-channel operation of such a system with a typical passive sensor is analyzed.

  19. 47 CFR 101.85 - Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... terrestrial fixed services to the fixed-satellite service (FSS). 101.85 Section 101.85 Telecommunication... Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite service (FSS...-satellite service (FSS). The rules in this section provide for a transition period during which...

  20. 47 CFR 101.85 - Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... terrestrial fixed services to the fixed-satellite service (FSS). 101.85 Section 101.85 Telecommunication... Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite service (FSS...-satellite service (FSS). The rules in this section provide for a transition period during which...

  1. 47 CFR 101.85 - Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... terrestrial fixed services to the fixed-satellite service (FSS). 101.85 Section 101.85 Telecommunication... Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite service (FSS...-satellite service (FSS). The rules in this section provide for a transition period during which...

  2. 47 CFR 101.85 - Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... terrestrial fixed services to the fixed-satellite service (FSS). 101.85 Section 101.85 Telecommunication... Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite service (FSS...-satellite service (FSS). The rules in this section provide for a transition period during which...

  3. 47 CFR 101.85 - Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... terrestrial fixed services to the fixed-satellite service (FSS). 101.85 Section 101.85 Telecommunication... Transition of the 18.3-19.3 GHz band from the terrestrial fixed services to the fixed-satellite service (FSS...-satellite service (FSS). The rules in this section provide for a transition period during which...

  4. 47 CFR 15.253 - Operation within the bands 46.7-46.9 GHz and 76.0-77.0 GHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-77.0 GHz is restricted to vehicle-mounted field disturbance sensors used as vehicle radar systems... operation is as a vehicle-mounted field disturbance sensor. Operation under the provisions of this section...-mounted field disturbance sensors, if the vehicle is in motion the power density of any emission...

  5. 47 CFR 15.253 - Operation within the bands 46.7-46.9 GHz and 76.0-77.0 GHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-77.0 GHz is restricted to vehicle-mounted field disturbance sensors used as vehicle radar systems... operation is as a vehicle-mounted field disturbance sensor. Operation under the provisions of this section...-mounted field disturbance sensors, if the vehicle is in motion the power density of any emission...

  6. 47 CFR 15.253 - Operation within the bands 46.7-46.9 GHz and 76.0-77.0 GHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) If the vehicle is not in motion, the power density of any emission within the bands specified in this... the power density of any emission within the bands specified in this section shall not exceed 60 µW... density of any emission within the bands specified in this section shallnot exceed 30 µW/cm2 at a...

  7. Design and analysis of an implantable CPW-fed X-monopole antenna for 2.45-GHz ISM band applications.

    PubMed

    Ashok Kumar, Srinivasan; Shanmuganantham, Thangavelu

    2014-03-01

    A novel antenna design that effectively covers the industrial, scientific, and medical (ISM) band at 2.45 GHz using an X-shaped structure with a coplanar waveguide (CPW) feed is described. The antenna has a compact size of 67.6 mm(3). The proposed design is effective for ISM band biotelemetry with a wakeup controller (2.45 GHz). An experimental prototype of the compact implantable CPW-fed X-shaped monopole antenna was fabricated on a biocompatible alumina Al2O3 ceramic substrate. The optimal antenna was fabricated and tested in minced tissue from the front leg of a pig and on a human body phantom liquid. The simulated and measured bandwidths are 180 MHz and 210 MHz in the ISM band, respectively. PMID:24404821

  8. Lattice dynamics and broad-band dielectric properties of multiferroic Pb(Fe{sub 1/2}Nb{sub 1/2})O{sub 3} ceramics

    SciTech Connect

    Mackeviciute, R.; Greicius, S.; Grigalaitis, R.; Banys, J.; Goian, V.; Nuzhnyy, D.; Kamba, S.; Holc, J.

    2015-02-28

    Complex dielectric properties of Pb(Fe{sub 1/2}Nb{sub 1/2})O{sub 3} ceramics were investigated in a broad frequency range from 100 Hz up to 90 THz. A broad dielectric anomaly was observed near the temperature of the ferroelectric phase transition (T{sub C1} = 376 K). Below 1 MHz, the anomaly is strongly influenced by conductivity of the sample, but higher frequency data taken up to 81 MHz reveal a broad and frequency independent peak at T{sub C1} typical for a diffuse ferroelectric phase transition. Surprisingly, dielectric permittivity measured at 37 GHz exhibits a peak shifted by 25 K above T{sub C1}, which indicates polar nanoregions with dynamics in microwave frequency region. A dielectric relaxation, which appears in THz region below 700 K, slows down towards T{sub C1} and again hardens below T{sub C2} = 356 K. This central mode drives both phase transitions, so they belong to order–disorder type, although the polar phonons exhibit anomalies near both phase transitions. In the paraelectric phase, infrared reflectivity spectra correspond to local Fm3{sup ¯}m structure due to short-range chemical ordering of Fe and Nb cations on the B perovskite sites. Moreover, each polar phonon is split due to two different cations on the B sites. Recently, Manley et al. [Nat. Commun. 5, 3683 (2014)] proposed a new mechanism of creation of polar nanoregions in relaxor ferroelectrics. They argued, based on their inelastic neutron scattering studies of PMN–PT, that the TO1 phonon is split and interaction of both components gives rise to so called Anderson phonon localization, which can produce regions of trapped standing waves and these waves induce polar nanoregions in relaxors. We cannot exclude or confirm this mechanism, but we show that the splitting of polar phonons is a common feature for all complex perovskites with relaxor ferroelectric behavior and it can be also observed in canonical ferroelectric BaTiO{sub 3}, where the soft mode is split in

  9. Lattice dynamics and broad-band dielectric properties of multiferroic Pb(Fe1/2Nb1/2)O3 ceramics

    NASA Astrophysics Data System (ADS)

    Mackeviciute, R.; Goian, V.; Greicius, S.; Grigalaitis, R.; Nuzhnyy, D.; Holc, J.; Banys, J.; Kamba, S.

    2015-02-01

    Complex dielectric properties of Pb(Fe1/2Nb1/2)O3 ceramics were investigated in a broad frequency range from 100 Hz up to 90 THz. A broad dielectric anomaly was observed near the temperature of the ferroelectric phase transition (TC1 = 376 K). Below 1 MHz, the anomaly is strongly influenced by conductivity of the sample, but higher frequency data taken up to 81 MHz reveal a broad and frequency independent peak at TC1 typical for a diffuse ferroelectric phase transition. Surprisingly, dielectric permittivity measured at 37 GHz exhibits a peak shifted by 25 K above TC1, which indicates polar nanoregions with dynamics in microwave frequency region. A dielectric relaxation, which appears in THz region below 700 K, slows down towards TC1 and again hardens below TC2 = 356 K. This central mode drives both phase transitions, so they belong to order-disorder type, although the polar phonons exhibit anomalies near both phase transitions. In the paraelectric phase, infrared reflectivity spectra correspond to local F m 3 ¯ m structure due to short-range chemical ordering of Fe and Nb cations on the B perovskite sites. Moreover, each polar phonon is split due to two different cations on the B sites. Recently, Manley et al. [Nat. Commun. 5, 3683 (2014)] proposed a new mechanism of creation of polar nanoregions in relaxor ferroelectrics. They argued, based on their inelastic neutron scattering studies of PMN-PT, that the TO1 phonon is split and interaction of both components gives rise to so called Anderson phonon localization, which can produce regions of trapped standing waves and these waves induce polar nanoregions in relaxors. We cannot exclude or confirm this mechanism, but we show that the splitting of polar phonons is a common feature for all complex perovskites with relaxor ferroelectric behavior and it can be also observed in canonical ferroelectric BaTiO3, where the soft mode is split in paraelectric phase due to a strong lattice anharmonicity.

  10. A 1.8-3 GHz-band high efficiency GaAs pHEMT power amplifier MMIC

    NASA Astrophysics Data System (ADS)

    Qin, Ge; Hongqi, Tao; Xuming, Yu

    2015-12-01

    This paper describes an S-band wideband high efficiency power amplifier based on the Nanjing Electron Device Institute's GaAs pHEMT monolithic microwave integrated circuit (MMIC) technology. To realize high efficiency, the two stage power amplifier is designed with a driver ratio of 1 : 8. The low-pass filter/high-pass filter combined matching circuit is applied to the amplifier to reduce the chip size, as well as to realize the optimum impedances over a wide bandwidth for high efficiency at each stage. Biased at class AB under a drain supply voltage of 5 V, the amplifier delivers 33-34 dBm saturated output power across the frequency range of 1.8 to 3 GHz with associated power-added efficiency of 35%-45% and very flat power gain of 25-26 dB in CW mode. The size of this MMIC is very compact with 2.7 × 2.75 mm2.

  11. Broadband Upgrade for the 1.668-GHz (L-Band) Radio Astronomy Feed System on the DSN 70-m Antennas

    NASA Astrophysics Data System (ADS)

    Hoppe, D.; Khayatian, B.; Lopez, B.; Torrez, T.; Long, E.; Sosnowski, J.; Franco, M.; Teitelbaum, L.

    2015-08-01

    Currently, each of the three Deep Space Network (DSN) 70-m antennas provides a narrowband, 1.668-GHz (L-band) receive capability for radio astronomy observations. This capability is delivered by a large feedhorn mounted on the exterior of one of the feedcones. It provides a single polarization into a pair of redundant low-noise amplifiers. Recently, funding was obtained to upgrade this system to wideband (1.4-1.9 GHz) dual-polarization operation. This required development of a new feedhorn, polarizer, orthomode transducer (OMT), and waveguide transitions. In this article, we describe the design and laboratory testing of these components.

  12. Demonstrations of 10 and 40 Gbps upstream transmissions using 1.2 GHz RSOA-based ONU in long-reach access networks

    NASA Astrophysics Data System (ADS)

    Yeh, C. H.; Chow, C. W.; Wu, Y. F.; Chen, H. Y.

    2012-03-01

    Carrier-distributed long-reach passive optical network (LR-PON) is a promising candidate for future access networks. In this work, we analyze and compare the 4 × 2.5 Gb/s and 4 × 10 Gb/s upstream traffics in a carrier-distributed LR-PON using four wavelength-multiplexed 2.5 Gb/s on-off keying (OOK) and 10 Gb/s optical orthogonal frequency division multiplexing-quadrature amplitude modulation (OFDM-QAM) signals. Four commercial 1.2 GHz bandwidth reflective semiconductor optical amplifiers (RSOAs) are used in each optical networking unit (ONU) for the generation of the upstream signal. Due to the limited bandwidth of the RSOA, only up to 2.5 Gb/s upstream OOK signal can be generated. However, by using the spectral efficient modulation, such as OFDM-QAM, 10 Gb/s data rate can be achieved. 20, 50 and 75 km fiber transmissions are also compared using the two different kinds of modulation respectively.

  13. A New 100-GHz Band Two-Beam Sideband-Separating SIS Receiver for Z-Machine on the NRO 45-m Radio Telescope

    NASA Astrophysics Data System (ADS)

    Nakajima, T.; Kimura, K.; Nishimura, A.; Iwashita, H.; Miyazawa, C.; Sakai, T.; Iono, D.; Kohno, K.; Kawabe, R.; Kuno, N.; Ogawa, H.; Asayama, S.; Tamura, T.; Noguchi, T.

    2013-03-01

    We have developed a two-beam waveguide-type dual-polarization sideband-separating SIS receiver system in the 100-GHz band for z-machine on the 45-m radio telescope at the Nobeyama Radio Observatory. The receiver is intended for astronomical use in searching for highly redshifted spectral lines from galaxies of unknown redshift. This receiver has two beams, which have 45'' of beam separation and allow for observation with the switch in the on-on position. The receiver of each beam is composed of an ortho-mode transducer and two sideband-separating SIS mixers, which are both based on a waveguide technique, and the receiver has four intermediate frequency bands of 4.0-8.0 GHz. Over the radio frequency range of 80-116 GHz, the single-sideband receiver noise temperature is lower than about 50 K, and the image rejection ratios are greater than 10 dB in most of the same frequency range. The new receiver system has been installed in the telescope, and we successfully observed a 12CO (J = 3-2) emission line toward a cloverleaf quasar at z = 2.56, which validates the performance of the receiver system. The SSB noise temperature of the system, including the atmosphere, is typically 150-300 K at a radio frequency of 97 GHz. We have begun a blind search of high-J CO toward high-z submillimeter galaxies.

  14. Ocean Surface Emissivity at L-band (1.4 GHz): The Dependence on Salinity and Roughness

    NASA Astrophysics Data System (ADS)

    Le Vine, D. M.; Lang, R. H.; Wentz, F. J.; Meissner, T.

    2012-12-01

    A characterization of the emissivity of sea water at L-band is important for the remote sensing of sea surface salinity. Measurements of salinity are currently being made in the radio astronomy band at 1.413 GHz by ESA's Soil Moisture and Ocean Salinity (SMOS) mission and NASA's Aquarius instrument aboard the Aquarius/SAC-D observatory. The goal of both missions is accuracy on the order of 0.2 psu. This requires accurate knowledge of the dielectric constant of sea water as a function of salinity and temperature and also the effect of waves (roughness). The former determines the emissivity of an ideal (i.e. flat) surface and the later is the major source of error from predictions based on a flat surface. These two aspects of the problem of characterizing the emissivity are being addressed in the context of the Aquarius mission. First, laboratory measurements are being made of the dielectric constant of sea water. This is being done at the George Washington University using a resonant cavity. In this technique, sea water of known salinity and temperature is fed into the cavity along its axis through a narrow tube. The sea water changes the resonant frequency and Q of the cavity which, if the sample is small enough, can be related to the dielectric constant of the sample. An extensive set of measurements have been conducted at 1.413 GHz to develop a model for the real and imaginary part of the dielectric constant as a function of salinity and temperature. The results are compared to the predictions of models based on parameterization of the Debye resonance of the water molecule. The models and measurements are close; however, the differences are significant for remote sensing of salinity. This is especially true at low temperatures where the sensitivity to salinity is lowest. Second, observations from Aquarius are being used to develop a model for the effect of wind-driven roughness (waves) on the emissivity in the open ocean. This is done by comparing the measured

  15. X-Ray Emitting GHz-Peaked Spectrum Galaxies: Testing a Dynamical-Radiative Model with Broad-Band Spectra

    SciTech Connect

    Ostorero, L.; Moderski, R.; Stawarz, L.; Diaferio, A.; Kowalska, I.; Cheung, C.C.; Kataoka, J.; Begelman, M.C.; Wagner, S.J.; /Heidelberg Observ.

    2010-06-07

    In a dynamical-radiative model we recently developed to describe the physics of compact, GHz-Peaked-Spectrum (GPS) sources, the relativistic jets propagate across the inner, kpc-sized region of the host galaxy, while the electron population of the expanding lobes evolves and emits synchrotron and inverse-Compton (IC) radiation. Interstellar-medium gas clouds engulfed by the expanding lobes, and photoionized by the active nucleus, are responsible for the radio spectral turnover through free-free absorption (FFA) of the synchrotron photons. The model provides a description of the evolution of the GPS spectral energy distribution (SED) with the source expansion, predicting significant and complex high-energy emission, from the X-ray to the {gamma}-ray frequency domain. Here, we test this model with the broad-band SEDs of a sample of eleven X-ray emitting GPS galaxies with Compact-Symmetric-Object (CSO) morphology, and show that: (i) the shape of the radio continuum at frequencies lower than the spectral turnover is indeed well accounted for by the FFA mechanism; (ii) the observed X-ray spectra can be interpreted as non-thermal radiation produced via IC scattering of the local radiation fields off the lobe particles, providing a viable alternative to the thermal, accretion-disk dominated scenario. We also show that the relation between the hydrogen column densities derived from the X-ray (N{sub H}) and radio (N{sub HI}) data of the sources is suggestive of a positive correlation, which, if confirmed by future observations, would provide further support to our scenario of high-energy emitting lobes.

  16. Studying integrated silicon-lens antennas for radio communication systems operated in the 60 GHz frequency band

    NASA Astrophysics Data System (ADS)

    Artemenko, A. A.; Mal'tsev, A. A.; Maslennikov, R. O.; Sevastyanov, A. G.; Ssorin, V. N.

    2013-01-01

    We consider the development of an integrated lens antenna for LAN radio communication systems operated in the 60 GHz frequency band. The antenna is an extended hemispherical silicon lens. On its flat surface, a microstrip antenna element is located. The use of silicon, which has a dielectric permittivity ɛ = 11.7, as the lens material ensures the maximum range of scanning angles for the minimum axial size of the lens. The approximate analytical formulas, which are used for initial calculations of the lens parameters, allow one to evaluate the basic parameters of the lens antenna integrated with the microstrip antenna element. For further optimizing the parameters of the lens and the antenna element, 3D simulation of the electromagnetic-field distribution was performed. Based on its results, we have developed and manufactured extended hemispherical silicon lenses, which had radii of 6 and 12 mm. The planar microstrip antenna element was manufactured by the low temperature co-fired ceramics (LTCC) technology. The results of simulation and experimental studies of the manufactured prototypes demonstrate that the developed lens antennas has directivities of 17.6 and 23.1 dBi for lenses with radii of 6 and 12 mm, respectively. In this case, the maximum beam deflection angle is achieved, which is equal to 55°, while the permissible decrease in the directivity is no more than 6 dBi compared with the case of a non-deflected beam. The obtained results show that the developed integrated lens antennas can find applications in high-speed radio communication systems operated in the millimeter-wave range.

  17. Improved Constraints on Cosmology and Foregrounds from BICEP2 and Keck Array Cosmic Microwave Background Data with Inclusion of 95 GHz Band

    NASA Astrophysics Data System (ADS)

    BICEP2 Collaboration; Keck Array Collaboration; Ade, P. A. R.; Ahmed, Z.; Aikin, R. W.; Alexander, K. D.; Barkats, D.; Benton, S. J.; Bischoff, C. A.; Bock, J. J.; Bowens-Rubin, R.; Brevik, J. A.; Buder, I.; Bullock, E.; Buza, V.; Connors, J.; Crill, B. P.; Duband, L.; Dvorkin, C.; Filippini, J. P.; Fliescher, S.; Grayson, J.; Halpern, M.; Harrison, S.; Hilton, G. C.; Hui, H.; Irwin, K. D.; Karkare, K. S.; Karpel, E.; Kaufman, J. P.; Keating, B. G.; Kefeli, S.; Kernasovskiy, S. A.; Kovac, J. M.; Kuo, C. L.; Leitch, E. M.; Lueker, M.; Megerian, K. G.; Netterfield, C. B.; Nguyen, H. T.; O'Brient, R.; Ogburn, R. W.; Orlando, A.; Pryke, C.; Richter, S.; Schwarz, R.; Sheehy, C. D.; Staniszewski, Z. K.; Steinbach, B.; Sudiwala, R. V.; Teply, G. P.; Thompson, K. L.; Tolan, J. E.; Tucker, C.; Turner, A. D.; Vieregg, A. G.; Weber, A. C.; Wiebe, D. V.; Willmert, J.; Wong, C. L.; Wu, W. L. K.; Yoon, K. W.

    2016-01-01

    We present results from an analysis of all data taken by the BICEP2 and Keck Array cosmic microwave background (CMB) polarization experiments up to and including the 2014 observing season. This includes the first Keck Array observations at 95 GHz. The maps reach a depth of 50 nK deg in Stokes Q and U in the 150 GHz band and 127 nK deg in the 95 GHz band. We take auto- and cross-spectra between these maps and publicly available maps from WMAP and Planck at frequencies from 23 to 353 GHz. An excess over lensed Λ CDM is detected at modest significance in the 95 ×150 B B spectrum, and is consistent with the dust contribution expected from our previous work. No significant evidence for synchrotron emission is found in spectra such as 23 ×95 , or for correlation between the dust and synchrotron sky patterns in spectra such as 23 ×353 . We take the likelihood of all the spectra for a multicomponent model including lensed Λ CDM , dust, synchrotron, and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r ) using priors on the frequency spectral behaviors of dust and synchrotron emission from previous analyses of WMAP and Planck data in other regions of the sky. This analysis yields an upper limit r0.05<0.09 at 95% confidence, which is robust to variations explored in analysis and priors. Combining these B -mode results with the (more model-dependent) constraints from Planck analysis of CMB temperature plus baryon acoustic oscillations and other data yields a combined limit r0.05<0.07 at 95% confidence. These are the strongest constraints to date on inflationary gravitational waves.

  18. Improved Constraints on Cosmology and Foregrounds from BICEP2 and Keck Array Cosmic Microwave Background Data with Inclusion of 95 GHz Band.

    PubMed

    Ade, P A R; Ahmed, Z; Aikin, R W; Alexander, K D; Barkats, D; Benton, S J; Bischoff, C A; Bock, J J; Bowens-Rubin, R; Brevik, J A; Buder, I; Bullock, E; Buza, V; Connors, J; Crill, B P; Duband, L; Dvorkin, C; Filippini, J P; Fliescher, S; Grayson, J; Halpern, M; Harrison, S; Hilton, G C; Hui, H; Irwin, K D; Karkare, K S; Karpel, E; Kaufman, J P; Keating, B G; Kefeli, S; Kernasovskiy, S A; Kovac, J M; Kuo, C L; Leitch, E M; Lueker, M; Megerian, K G; Netterfield, C B; Nguyen, H T; O'Brient, R; Ogburn, R W; Orlando, A; Pryke, C; Richter, S; Schwarz, R; Sheehy, C D; Staniszewski, Z K; Steinbach, B; Sudiwala, R V; Teply, G P; Thompson, K L; Tolan, J E; Tucker, C; Turner, A D; Vieregg, A G; Weber, A C; Wiebe, D V; Willmert, J; Wong, C L; Wu, W L K; Yoon, K W

    2016-01-22

    We present results from an analysis of all data taken by the BICEP2 and Keck Array cosmic microwave background (CMB) polarization experiments up to and including the 2014 observing season. This includes the first Keck Array observations at 95 GHz. The maps reach a depth of 50 nK deg in Stokes Q and U in the 150 GHz band and 127 nK deg in the 95 GHz band. We take auto- and cross-spectra between these maps and publicly available maps from WMAP and Planck at frequencies from 23 to 353 GHz. An excess over lensed ΛCDM is detected at modest significance in the 95×150 BB spectrum, and is consistent with the dust contribution expected from our previous work. No significant evidence for synchrotron emission is found in spectra such as 23×95, or for correlation between the dust and synchrotron sky patterns in spectra such as 23×353. We take the likelihood of all the spectra for a multicomponent model including lensed ΛCDM, dust, synchrotron, and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r) using priors on the frequency spectral behaviors of dust and synchrotron emission from previous analyses of WMAP and Planck data in other regions of the sky. This analysis yields an upper limit r_{0.05}<0.09 at 95% confidence, which is robust to variations explored in analysis and priors. Combining these B-mode results with the (more model-dependent) constraints from Planck analysis of CMB temperature plus baryon acoustic oscillations and other data yields a combined limit r_{0.05}<0.07 at 95% confidence. These are the strongest constraints to date on inflationary gravitational waves. PMID:26849583

  19. The Low Band Observatory (LOBO): Expanding the VLA Low Frequency Commensal System for Continuous, Broad-band, sub-GHz Observations

    NASA Astrophysics Data System (ADS)

    Kassim, Namir E.; Clarke, Tracy E.; Helmboldt, Joseph F.; Peters, Wendy M.; Brisken, Walter; Hyman, Scott D.; Polisensky, Emil; Hicks, Brian

    2015-01-01

    The Naval Research Laboratory (NRL) and the National Radio Astronomy Observatory (NRAO) are currently commissioning the VLA Low Frequency Ionosphere and Transient Experiment (VLITE) on a subset of JVLA antennas at modest bandwidth. Its bounded scientific goals are to leverage thousands of JVLA on-sky hours per year for ionospheric and transient studies, and to demonstrate the practicality of a prime-focus commensal system on the JVLA. Here we explore the natural expansion of VLITE to a full-antenna, full-bandwidth Low Band Observatory (LOBO) that would follow naturally from a successful VLITE experience. The new Low Band JVLA receivers, coupled with the existing primary focus feeds, can access two frequency bands: 4 band (54 - 86 MHz) and P band (236-492 MHz). The 4 band feeds are newly designed and now undergoing testing. If they prove successful then they can be permanently mounted at the primary focus, unlike their narrow band predecessors. The combination of Low Band receivers and fixed, primary-focus feeds could provide continuous, broad-band data over two complimentary low-frequency bands. The system would also leverage the relatively large fields-of-view of ~10 degrees at 4 band, and ~2.5 degrees at P band, coupling an excellent survey capability with a natural advantage for serendipitous discoveries. We discuss the compelling science case that flows from LOBO's robust imaging and time domain capabilities coupled with thousands of hours of wide-field, JVLA observing time each year. We also touch on the possibility to incorporate Long Wavelength Array (LWA) stations as additional 'dishes' through the LOBO backend, to improve calibration and sensitivity in LOBO's 4 band.

  20. Measurements of Ocean Surface Scattering Using an Airborne 94-GHz Cloud Radar: Implication for Calibration of Airborne and Spaceborne W-band Radars

    NASA Technical Reports Server (NTRS)

    Li, Li-Hua; Heymsfield, Gerald M.; Tian, Lin; Racette, Paul E.

    2004-01-01

    Scattering properties of the Ocean surface have been widely used as a calibration reference for airborne and spaceborne microwave sensors. However, at millimeter-wave frequencies, the ocean surface backscattering mechanism is still not well understood, in part, due to the lack of experimental measurements. During the Cirrus Regional Study of Tropical Anvils and Cirrus Layers-Florida Area Cirrus Experiment (CRYSTAL-FACE), measurements of ocean surface backscattering were made using a 94-GHz (W-band) cloud radar onboard a NASA ER-2 high-altitude aircraft. The measurement set includes the normalized Ocean surface cross section over a range of the incidence angles under a variety of wind conditions. Analysis of the radar measurements shows good agreement with a quasi-specular scattering model. This unprecedented dataset enhances our knowledge about the Ocean surface scattering mechanism at 94 GHz. The results of this work support the proposition of using the Ocean surface as a calibration reference for airborne millimeter-wave cloud radars and for the ongoing NASA CloudSat mission, which will use a 94-GHz spaceborne cloud radar for global cloud measurements.

  1. Statistical and Prediction modeling of the Ka Band Using Experimental Results from ACTS Propagation Terminals at 20.185 and 27.505 GHZ

    NASA Technical Reports Server (NTRS)

    Ogunwuyi, Oluwatosin O.

    2004-01-01

    With the increase in demand for wireless communication services, most of the operating frequency bands have become very congested. The increase of wireless costumers is only fractional contribution to this phenomenon. The demand for more services such as video streams and internet explorer which require a lot of band width has been a more significant contributor to the congestion in a communication system. One way to increase the amount of information or data per unit of time transmitted with in a wireless communication system is to use a higher radio frequency. However in spite the advantage available in the using higher frequency bands such as, the Ka-band, higher frequencies also implies short wavelengths. And shorter wavelengths are more susceptible to rain attenuation. Until the Advanced Communication Technology Satellite (ACTS) was launched, the Ka- band frequency was virtually unused - the majority of communication satellites operated in lower frequency bands called the C- and Ku- bands. Ka-band is desirable because its higher frequency allows wide bandwidth applications, smaller spacecraft and ground terminal components, and stronger signal strength. Since the Ka-band is a high frequency band, the millimeter wavelengths of the signals are easily degraded by rain. This problem known as rain fade or rain attenuation The Advanced Communication Technology Satellite (ACTS) propagation experiment has collected 5 years of Radio Frequency (RF) attenuation data from December 1993 to November 1997. The objective of my summer work is to help develop the statistics and prediction techniques that will help to better characterize the Ka Frequency band. The statistical analysis consists of seasonal and cumulative five-year attenuation statistics for the 20.2 and 27.5 GHz. The cumulative five-year results give the link outage that occurs for a given link margin. The experiment has seven ground station terminals that can be attributed to a unique rain zone climate. The

  2. Impact of high power interference sources in planning and deployment of wireless sensor networks and devices in the 2.4 GHz frequency band in heterogeneous environments.

    PubMed

    Iturri, Peio López; Nazábal, Juan Antonio; Azpilicueta, Leire; Rodriguez, Pablo; Beruete, Miguel; Fernández-Valdivielso, Carlos; Falcone, Francisco

    2012-01-01

    In this work, the impact of radiofrequency radiation leakage from microwave ovens and its effect on 802.15.4 ZigBee-compliant wireless sensor networks operating in the 2.4 GHz Industrial Scientific Medical (ISM) band is analyzed. By means of a novel radioplanning approach, based on electromagnetic field simulation of a microwave oven and determination of equivalent radiation sources applied to an in-house developed 3D ray launching algorithm, estimation of the microwave oven’s power leakage is obtained for the complete volume of an indoor scenario. The magnitude and the variable nature of the interference is analyzed and the impact in the radio link quality in operating wireless sensors is estimated and compared with radio channel measurements as well as packet measurements. The measurement results reveal the importance of selecting an adequate 802.15.4 channel, as well as the Wireless Sensor Network deployment strategy within this type of environment, in order to optimize energy consumption and increase the overall network performance. The proposed method enables one to estimate potential interference effects in devices operating within the 2.4 GHz band in the complete scenario, prior to wireless sensor network deployment, which can aid in achieving the most optimal network topology. PMID:23202228

  3. Impact of High Power Interference Sources in Planning and Deployment of Wireless Sensor Networks and Devices in the 2.4 GHz Frequency Band in Heterogeneous Environments

    PubMed Central

    Iturri, Peio López; Nazábal, Juan Antonio; Azpilicueta, Leire; Rodriguez, Pablo; Beruete, Miguel; Fernández-Valdivielso, Carlos; Falcone, Francisco

    2012-01-01

    In this work, the impact of radiofrequency radiation leakage from microwave ovens and its effect on 802.15.4 ZigBee-compliant wireless sensor networks operating in the 2.4 GHz Industrial Scientific Medical (ISM) band is analyzed. By means of a novel radioplanning approach, based on electromagnetic field simulation of a microwave oven and determination of equivalent radiation sources applied to an in-house developed 3D ray launching algorithm, estimation of the microwave oven's power leakage is obtained for the complete volume of an indoor scenario. The magnitude and the variable nature of the interference is analyzed and the impact in the radio link quality in operating wireless sensors is estimated and compared with radio channel measurements as well as packet measurements. The measurement results reveal the importance of selecting an adequate 802.15.4 channel, as well as the Wireless Sensor Network deployment strategy within this type of environment, in order to optimize energy consumption and increase the overall network performance. The proposed method enables one to estimate potential interference effects in devices operating within the 2.4 GHz band in the complete scenario, prior to wireless sensor network deployment, which can aid in achieving the most optimal network topology. PMID:23202228

  4. 76 FR 67070 - Operation of Wireless Communications Services in the 2.3 GHz Band; Establishment of Rules and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-31

    ...), 27.73(a), and 27.73(b) of the Commission's rules published at 75 FR 45058, August 2, 2010, are... and Policies for the Digital Audio Radio Satellite Service in the 2310-2360 MHz Frequency Band AGENCY... Audio Radio Satellite Service in the 2310-2360 MHz Frequency Band (WCS and SDARS) proceeding, to...

  5. Frequency band justifications for passive sensors, 1 to 10 GHz. [for monitoring earth resources and the environment

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Remote sensor systems operating in the microwave region of the frequency spectrum provide information unobtainable with basic imaging techniques such as photography, television, or multispectral imaging. The frequency allocation requirements for passive microwave sensors used in the earth exploration satellite and space research services are presented for: (1) agriculture, forestry, and range resources; (2) land use survey and mapping: (3) water resources; (4) weather and climate; (5) environmental quality; and (6) marine resources, estuarine and oceans. Because measurements are required simultaneously in multiple frequency bands to adequately determine values of some phenomena, the relationships between frequency bands are discussed. The various measurement accuracies, dynamic range, resolutions and frequency needs are examined. A band-by-band summary of requirements, unique aspects, and sharing analyses of the required frequency bands is included.

  6. Design of Compact Penta-Band and Hexa-Band Microstrip Antennas

    NASA Astrophysics Data System (ADS)

    Srivastava, Kunal; Kumar, Ashwani; Kanaujia, Binod K.

    2016-03-01

    This paper presents the design of two multi-band microstrip antennas. The antenna-1 gives Penta-Band and antenna-2 gives Hexa-band in the WLAN band. The frequency bands of the antenna-1 are Bluetooth 2.47 GHz (2.43 GHz-2.54 GHz), WiMax band 3.73 GHz (3.71 GHz-3.77 GHz), WLAN 5.1 GHz (4.99 GHz-5.13 GHz), upper WLAN 6.36 GHz (6.29 GHz-6.43 GHz), C band band 7.42 GHz (7.32 GHz-7.50 GHz) and the antenna-2 are WLAN band 2.6 GHz (2.56 GHz-2.63 GHz), 3.0 GHz (2.94 GHz-3.05 GHz), WiMax band 3.4 GHz (3.34 GHz-3.55 GHz), 4.85 GHz (4.81 GHz-4.92 GHz), WLAN 5.3 GHz (5.27 GHz-5.34 GHz) and upper WLAN 6.88 GHz. Both the antennas are fabricated and their measured results are presented to validate the simulated results. Proposed antennas have compact sizes and good radiation performances.

  7. Assessment of corneal hydration sensing in the terahertz band: in vivo results at 100 GHz

    PubMed Central

    Taylor, Zachary; Tewari, Pria; Sung, Shijun; Maccabi, Ashkan; Singh, Rahul; Culjat, Martin; Grundfest, Warren; Hubschman, Jean-Pierre; Brown, Elliott

    2012-01-01

    Abstract. Terahertz corneal hydration sensing has shown promise in ophthalmology applications and was recently shown to be capable of detecting water concentration changes of about two parts in a thousand in ex vivo corneal tissues. This technology may be effective in patient monitoring during refractive surgery and for early diagnosis and treatment monitoring in diseases of the cornea. In this work, Fuchs dystrophy, cornea transplant rejection, and keratoconus are discussed, and a hydration sensitivity of about one part in a hundred is predicted to be needed to successfully distinguish between diseased and healthy tissues in these applications. Stratified models of corneal tissue reflectivity are developed and validated using ex vivo spectroscopy of harvested porcine corneas that are hydrated using polyethylene glycol solutions. Simulation of the cornea’s depth-dependent hydration profile, from 0.01 to 100 THz, identifies a peak in intrinsic reflectivity contrast for sensing at 100 GHz. A 100 GHz hydration sensing system is evaluated alongside the current standard ultrasound pachymetry technique to measure corneal hydration in vivo in four rabbits. A hydration sensitivity, of three parts per thousand or better, was measured in all four rabbits under study. This work presents the first in vivo demonstration of remote corneal hydration sensing. PMID:23085925

  8. Tuning of 2.998 GHz S-band hybrid buncher for injector upgrade of LINAC II at DESY

    NASA Astrophysics Data System (ADS)

    Nie, Y. C.; Liebig, C.; Hüning, M.; Schmitz, M.

    2014-10-01

    The injector upgrade of LINAC II at DESY aims to improve its reliability and mitigate the radiological activation of components due to electron loss at relatively high energy of hundreds of MeV. Therefore, a 2.998 GHz hybrid buncher has been developed and will be installed in between an existing 2.998 GHz pre-buncher and LINAC II. It comprises a 1-cell standing-wave (SW) section for rapid electron acceleration and a 13-cells traveling-wave (TW) section for further beam bunching and acceleration. This paper focuses on its radio-frequency tuning procedure. The tuning strategy combines a non-resonant bead-pull measurement of complex electric field and a linear model for local reflection coefficient calculation. It is demonstrated that imaginary part of the local reflection coefficient represents the field distribution straightforwardly, based on which the structure can be tuned from cell to cell. During tuning, special attention has been paid to the field enhancement in the SW section to ensure its beam-capturing capability. Field amplitude and phase, global and local reflection coefficients have been analyzed for two different frequencies simultaneously, i.e. the intrinsic frequency of the structure and the target frequency, to avoid over-tuning. The tuning result is satisfying. For the target frequency, field unflatness of the TW section has been reduced from ±9% to ±4%, and field in the SW section has been enhanced significantly. Meanwhile, in the TW section, the deviation of phase advances between adjacent cells from the nominal value 120° has been reduced from the range ±5° to ±2°. By using ASTRA simulation, it has been verified that the residual detuning of the structure is acceptable in view of the beam dynamics performance.

  9. Delta I = 1 staggering effect for negative parity rotational bands with K = 1/2 in W/Os/Pt odd-mass nuclei

    NASA Astrophysics Data System (ADS)

    Taha, M. M.

    2015-11-01

    The anomalous negative-parity bands of odd-mass nuclei W/Os/Pt for N = 103 isotones are studied within the framework of particle rotor model (PRM). The phenomenon of Δ I = 1 staggering or signature splitting in energies occurs as one plots the gamma transitional energy over spin (EGOS) versus spin for the 1/2-[521] band originating from N = 5 single particle orbital. The rotational band with K = 1/2 separates into two signature partners. The levels with I = 1/2, 5/2, 9/2,… are displaced relatively to the levels with I = 3/2,7/2,11/2,…. The deviations of the level energies from the rigid rotor values is described by Coriolis coupling.

  10. A 60-GHz-band 2 x 4 planar dipole array antenna module fabricated by 3-D SiP technology

    NASA Astrophysics Data System (ADS)

    Suematsu, Noriharu; Suzuki, Yuya; Yoshida, Satoshi; Tanifuji, Shoichi; Kameda, Suguru; Takagi, Tadashi; Tsubouchi, Kazuo

    2014-08-01

    A 2 × 4 phased array antenna module has been developed for 60-GHz-band short- range high-speed wireless communication terminals. To realize the required vertical distance between the antenna elements, the module is made of five sheets of multi-layered organic substrates vertically stacked with Cu balls, and the 1 x 4 dipole array antenna is placed on both the top and bottom organic substrates. To reduce the mutual coupling between the element antennas, a monolithic microwave integrated circuit (MMIC) is flip-chip mounted on the feed line of each element antenna. The Au-stud bump flip-chip mounting technique helps achieve a lower return loss in the transition section at the MMIC than the Au-wire bonded. The placement accuracy of each antenna element in the vertical direction, 60-GHz signal vertical interconnection between the substrates with Cu balls, and flip-chip mounting of the MMIC are confirmed by 3-D computed tomography (CT) scans.

  11. High-Resolution Inspection of the Space Shuttle External Tank Spray-on-Foam Insulation (SOFI) using Focused Millimeter Waves at D-Band (150 GHz)

    NASA Technical Reports Server (NTRS)

    Kharkovsky, S.; Zoughi, R.; Hepburn, F. L.

    2006-01-01

    Space Shuttle Columbia's catastrophic failure has been attributed to a piece of spray-on-foam insulation (SOFI) that was dislodged from the external tank and struck the leading edge of the left wing. A piece of SOFI was also dislodged in the recent Space Shuttle Discovery's flight. Clearly, there is a great and urgent need to inspect the external tank SOFI and other similar insulating structures (including the acreage heat tile) in a reliable and robust fashion. In the past two years, millimeter wave nondestructive testing methods, using both real and synthetic focusing techniques, have shown great potential for this purpose. Recently obtained real-focused images from several different and complex SOFI panels have demonstrated the utility of these methods as being viable, robust, repeatable, simple, portable and effective. D-band frequency range which covers a frequency spectrum of 110- 170 GHz is well-suited for this purpose given the nature of the foam which causes significant scattering at much higher frequencies. This paper presents the results of using continuous-wave (CW) reflectometry conducted on several typical and complex SOFI panes at 150 GHz.

  12. A 5.4-9.2 GHz 19.5 dB Complementary Metal-Oxide-Semiconductor Ultrawide-Band Receiver Front-End Low-Noise Amplifier

    NASA Astrophysics Data System (ADS)

    Azhari, Afreen; Kubota, Shinichi; Toya, Akihiro; Sasaki, Nobuo; Kikkawa, Takamaro

    2011-04-01

    In this work, we present an ultrawide-band (UWB) complementary metal-oxide-semiconductor (CMOS) low-noise amplifier (LNA) for wireless communication in the upper UWB band, that is, from 5.4-9.2 GHz bandwidth with a wide-band 50 Ω input matching network in front of the LNA. A three-stage cascode-topology-based LNA with high-transconductance MOS transistors, was employed to improve the voltage gain up to 23 dB at 7.5 GHz, with 4.5-9.2 GHz 3 dB bandwidth. The maximum output power S21 was 19.5 dB at 7.3 GHz, with 5.4-9.2 GHz 3 dB bandwidth. The input matching circuit was designed with a reduced number of passive elements, resulting in an input reflection coefficient S11 of less than -10 dB from 4.5-9.2 GHz. The noise figure of the LNA was as low as 3.5 dB and the input-referred third-order intercept point (IIP3) was -8 dBm. The LNA has output reflection coefficient S22 of less than -10 dB from 5-7 GHz and a good reverse isolation, that is, S12 of < -45 dB in the entire UWB, due to a cascode topology. The LNA was fabricated using 180 nm CMOS technology, which consumes 56 mW power at 1.8 V power supply. In this paper, we also demonstrate a wireless communication of 7 GHz Gaussian monocycle pulse (GMP) by horn antennas and the LNA from 20 cm transmission distance.

  13. 60-GHz-Band Switched-Beam Eight-Sector Antenna with SP8T Switch for 180° Azimuth Scan

    NASA Astrophysics Data System (ADS)

    Miura, Amane; Ohira, Masataka; Kitazawa, Shoichi; Ueba, Masazumi

    This paper proposes a new switched-beam eight-sector antenna for multi-gigabit wireless LAN in the 60-GHz band. Our antenna system introduces access-point (AP) and user-terminal (UT) antennas having the same sec θ pattern in the elevation plane so that the received signal power at the receiver is kept constant, independent of the position of the UT. For this system, an eight-sector antenna, a single-pole eight-throw (SP8T) switch, and a beam control unit are integrated as the switched-beam eight-sector antenna. The specifications of the antenna are wide bandwidth (≥3GHz), high-gain (≥13dBi at θ=66°), and wide coverage area in both azimuth (0° ≤ φ ≤ 180°) and elevation planes (0° ≤ θ ≤ 66°). The antenna beam is steered within the specified response time (which is short) by the Media Access Control (MAC). In our antenna, both high gain for a wide elevation angle and wide bandwidth are obtained by using the proposed closely spaced waveguide slot array antenna, which is used as each sector of the eight-sector antenna. The SP8T switch with the beam control unit enables 180° beam scan in the azimuth plane. In a component evaluation, the eight-sector antenna achieves a 10-dB return loss bandwidth of 8GHz with more than 40-dB port-to-port isolation. Radiation characteristics of the eight-sector antenna indicate that it covers 82% of the entire coverage area at the center frequency and that the coverage rate in the operating frequency band is from 78% to 88%. The performance of the SP8T switch and the beam control unit is verified by measuring the insertion loss at all eight ports and the switching response time. In the antenna system evaluation, measurement by using two prototype antennas as the AP and the UT antennas in the usage condition indicates that the measured received signal power meets the specified constant power for the specified wide elevation angle range, independent of the position of the UT. These experimental results verify the

  14. Comparing LDA-1/2, HSE03, HSE06 and G 0 W 0 approaches for band gap calculations of alloys

    NASA Astrophysics Data System (ADS)

    Pela, R. R.; Marques, M.; Teles, L. K.

    2015-12-01

    It has long been known that the local density approximation and the generalized gradient approximation do not furnish reliable band gaps, and one needs to go beyond these approximations to reliably describe these properties. Among alternatives are the use of hybrid functionals (HSE03 and HSE06 being popular), the GW approximation or the recently proposed LDA-1/2 method. In this work, we compare rigorously the performance of these four methods in describing the band gaps of alloys, employing the generalized quasi-chemical approach to treat the disorder of the alloy and to obtain judiciously the band gap for the entire compositional range. Zincblende InGaAs and InGaN were chosen as prototypes due to their importance in optoelectronic applications. The comparison between these four approaches was guided both by the agreement between the predicted band gap and the experimental one, and by the demanded computational effort (time and memory). We observed that the HSE06 method provided the most accurate results (in comparison with experiments), whereas, surprisingly, the LDA-1/2 method gave the best compromise between accuracy and computational resources. Due to its low computational cost and good accuracy, we decided to double the supercell used to describe the alloys, and employing LDA-1/2 we observed that the bowing parameter changed remarkably, only agreeing with the measured one for the larger supercell, where LDA-1/2 plays an important role.

  15. A spectral line survey of Orion KL in the bands 486-492 and 541-577 GHz with the Odin satellite. I. The observational data

    NASA Astrophysics Data System (ADS)

    Olofsson, A. O. H.; Persson, C. M.; Koning, N.; Bergman, P.; Bernath, P. F.; Black, J. H.; Frisk, U.; Geppert, W.; Hasegawa, T. I.; Hjalmarson, Å.; Kwok, S.; Larsson, B.; Lecacheux, A.; Nummelin, A.; Olberg, M.; Sandqvist, Aa.; Wirström, E. S.

    2007-12-01

    Aims:Spectral line surveys are useful since they allow identification of new molecules and new lines in uniformly calibrated data sets. The subsequent multi-transition analysis will provide improved knowledge of molecular abundances, cloud temperatures and densities, and may also reveal previously unsuspected blends of molecular lines, which otherwise may lead to erroneous conclusions. Nonetheless, large portions of the sub-millimetre spectral regime remain unexplored due to severe absorptions by H{2}O and O{2} in the terrestrial atmosphere. The purpose of the measurements presented here is to cover wavelength regions at and around 0.55 mm - regions largely unobservable from the ground. Methods: Using the Odin astronomy/aeronomy satellite, we performed the first spectral survey of the Orion KL molecular cloud core in the bands 486-492 and 541-576 GHz with rather uniform sensitivity (22-25 mK baseline noise). Odin's 1.1 m size telescope, equipped with four cryo-cooled tuneable mixers connected to broad band spectrometers, was used in a satellite position-switching mode. Two mixers simultaneously observed different 1.1 GHz bands using frequency steps of 0.5 GHz (25 h each). An on-source integration time of 20 h was achieved for most bands. The entire campaign consumed 1100 orbits, each containing one hour of serviceable astro-observation. Results: We identified 280 spectral lines from 38 known interstellar molecules (including isotopologues) having intensities in the range 80 to 0.05 K. An additional 64 weak lines remain unidentified. Apart from the ground state rotational 1{1,0}-1{0,1} transitions of ortho-H{2}O, H{2}18O and H{2}17O, the high energy 6{2,4}-7{1,7} line of para-H{2}O (Eu=867 K) and the HDO(2{0,2}-1{1,1}) line have been observed, as well as the 1{0}-0{1} lines from NH{3} and its rare isotopologue 15NH{3}. We suggest assignments for some unidentified features, notably the new interstellar molecules ND and SH-. Severe blends have been detected in the

  16. Assignment of the 290-nm electronic band system of indazole [1,2-benzodiazole] as π ∗ - π by rotational band contour analysis

    NASA Astrophysics Data System (ADS)

    Cané, E.; Trombetti, A.; Velino, B.; Caminati, W.

    1992-10-01

    The 0 00 band of the S1- S0 electronic absorption system of indazole at 290 nm has been analyzed, and the results of the computer simulation of its rotational contour have shown that this band is and {A}/{B} hybrid with an intensity ratio {A}/{B} = 1.22 . The S1- S0 electronic system is assigned as Ã1A'(ππ ∗)- X˜1A' . The same result has already been reached for benzimidazole (E. Cané et al., J. Mol. Spectrosc.150, 222-228 (1991)), and other ring-condensed aza-aromatic compounds although the relative amount of the type B and A components is different in each band. The transition moment is in the molecular plane nearly equidistant from the a- and b-inertial axes ( θ = ±42°).

  17. High resolution absorption spectroscopy of the ν1=2-6 acetylenic overtone bands of propyne: Spectroscopy and dynamics

    NASA Astrophysics Data System (ADS)

    Campargue, A.; Biennier, L.; Garnache, A.; Kachanov, A.; Romanini, D.; Herman, M.

    1999-11-01

    The rotationally resolved nν1 (n=2-6) overtone transitions of the CH acetylenic stretching of propyne (CH3-C≡C-H) have been recorded by using Fourier transform spectroscopy (n=2), various intracavity laser absorption spectrometers (n=3, 4, and 6) and cavity ring down spectroscopy (CRDS) (n=5). The 2ν1, 3ν1, and 6ν1 bands exhibit a well-resolved and mostly unperturbed J-rotational structure, whose analysis is reported. The 5ν1 band recorded by pulsed CRDS shows an unresolved rotational envelope. In the region of 12 700 cm-1, an anharmonic interaction is confirmed between 4ν1 and 3ν1+ν3+ν5. The band at a higher wave number in this dyad exhibits a partly resolved K-structure, whose analysis is reported. The mixing coefficient of the two interacting states is determined consistently using different procedures. The 1/35 anharmonic resonance evidenced in the 4ν1 manifold induces weaker intensity borrowing from the 2ν1 and 3ν1 levels to the ν1+ν3+ν5 and 2ν1+ν3+ν5 level, respectively, which have been predicted and identified. Several hot bands around the 2ν1, 3ν1, and 3ν1+ν3+ν5 bands arising from the ν9=1 and ν10=1 and 2 bending levels are identified and rotationally analyzed, also leading to determine x1,9 [-20.3(3) cm-1], x1,10 [-1.7975(75) cm-1], and x3,10 [-6.56 cm-1]. The J-clumps of the P and R branches in the 6ν1 band at 18 499 cm-1 show a Lorentzian homogeneous profile mostly J-independent with an average full width at half maximum (FWHM) of 0.17 cm-1, attributed to arising from the intramolecular vibrational energy redistribution towards the bath of vibrational states. A detailed comparative examination of the fine structure in all investigated nν1 (n=2 to 7) overtone bands and the similar behavior of the cold and hot bands arising from ν10=1 definitively suggests that a highly specific low-order anharmonic coupling, still unidentified, dominates the hierarchy of interaction mechanisms connecting the nν1 levels to the background

  18. Hearing thresholds of a harbor porpoise (Phocoena phocoena) for sweeps (1-2 kHz and 6-7 kHz bands) mimicking naval sonar signals.

    PubMed

    Kastelein, Ronald A; Hoek, Lean; de Jong, Christ A F

    2011-05-01

    The distance at which active naval sonar signals can be heard by harbor porpoises depends, among other factors, on the hearing thresholds of the species for those signals. Therefore the hearing sensitivity of a harbor porpoise was determined for 1 s up-sweep and down-sweep signals, mimicking mid-frequency and low-frequency active sonar sweeps (MFAS, 6-7 kHz band; LFAS, 1-2 kHz band). The 1-2 kHz sweeps were also tested with harmonics, as sonars sometimes produce these as byproducts of the fundamental signal. The hearing thresholds for up-sweeps and down-sweeps within each sweep pair were similar. The 50% detection threshold sound pressure levels (broadband, averaged over the signal duration) of the 1-2 kHz and 6-7 kHz sweeps were 75 and 67 dB re 1 μPa(2), respectively. Harmonic deformation of the 1-2 kHz sweeps reduced the threshold to 59 dB re 1 μPa(2). This study shows that the presence of harmonics in sonar signals can increase the detectability of a signal by harbor porpoises, and that tonal audiograms may not accurately predict the audibility of sweeps. LFAS systems, when designed to produce signals without harmonics, can operate at higher source levels than MFAS systems, at similar audibility distances for porpoises. PMID:21568440

  19. The vibration-rotation spectrum of DCP . The analysis of the fundamental bands ν1 and ν2, of the overtone band 2ν1, of the summation band ν1 + 2ν3, and of the difference band ν1 - ν2

    NASA Astrophysics Data System (ADS)

    Lavigne, Jacques; Pépin, Claude; Cabana, Aldée

    1983-05-01

    The vibration-rotation bands ν1, ν2, ν1 - ν2, ν1 + 2 ν3, and 2 ν1 have been recorded and analyzed. A simultaneous fit of 395 transitions, including those previously known, was made to obtain improved spectroscopic constant for D 12CP in 6 different vibrational states.

  20. High resolution GHz and THz (FTIR) spectroscopy and theory of parity violation and tunneling for 1,2-dithiine (C4H4S2) as a candidate for measuring the parity violating energy difference between enantiomers of chiral molecules.

    PubMed

    Albert, S; Bolotova, I; Chen, Z; Fábri, C; Horný, L'; Quack, M; Seyfang, G; Zindel, D

    2016-08-01

    We report high resolution spectroscopic results of 1,2-dithiine-(1,2-dithia-3,5-cyclohexadiene, C4H4S2) in the gigahertz and terahertz spectroscopic ranges and exploratory theoretical calculations of parity violation and tunneling processes in view of a possible experimental determination of the parity violating energy difference ΔpvE in this chiral molecule. Theory predicts that the parity violating energy difference between the enantiomers in their ground state (ΔpvE ≃ 1.1 × 10(-11)(hc) cm(-1)) is in principle measurable as it is much larger than the calculated tunneling splitting for the symmetrical potential ΔE± < 10(-24) (hc) cm(-1). With a planar transition state for stereomutation at about 2500 cm(-1) tunneling splitting becomes appreciable above 2300 cm(-1). This makes levels of well-defined parity accessible to parity selection by the available powerful infrared lasers and thus useful for one of the existing experimental approaches towards molecular parity violation. The new GHz spectroscopy leads to greatly improved ground state rotational parameters for 1,2-dithiine. These are used as starting points for the first successful analyses of high resolution interferometric Fourier transform infrared (FTIR, THz) spectra of the fundamentals ν17 (1308.873 cm(-1) or 39.23903 THz), ν22 (623.094 cm(-1) or 18.67989 THz) and ν3 (1544.900 cm(-1) or 46.314937 THz) for which highly accurate spectroscopic parameters are reported. The results are discussed in relation to current efforts to measure ΔpvE. PMID:27439591

  1. Design and construction of a high charge and high current 1-1/2 cell L-Band RF photocathode gun.

    SciTech Connect

    Conde, M. E.; Gai, W.; Konecny, R.; Power, J. G.; Schoessow, P.

    1999-03-26

    The Argonne Wakefield Accelerator has been successfully commissioned and used for conducting wakefield experiments in dielectric loaded structures and plasmas. Although the initial wakefield experiments were successful, higher drive beam quality would substantially improve the wakefield accelerating gradients. In this paper we present a new 1-1/2 cell L-band photocathode RF gun design. This gun will produce 10-100 nC beam with 2-5 ps rms pulse length and normalized emittance less than 100 mm mrad. The final gun design and numerical simulations of the beam dynamics are presented.

  2. Spectrum allocations above 40 GHz

    NASA Technical Reports Server (NTRS)

    Katzenstein, W. E.; Moore, R. P.; Kimball, H. G.

    1981-01-01

    The 1979 World Administrative Radio Conference (WARC-79) revised the International Table of Frequency Allocations to reflect increased interest and activity in the region of the EM spectrum above 40 GHz. The total width of the spectrum allocated (235 GHz) in the region above 40 GHz indicates the extent of this new spectrum resource, made accessible by advances in the state-of-the-art of telecommunications equipment. There are some striking differences between the approach to allocation above and below 40 GHz. For example, there are not bands allocated exclusively. This reflects the characteristics of propagation and the small antenna beamwidths achievable at these frequencies. Attention is given to atmospheric window and absorption band limits, allocations to satellite services, allocations to scientific services, allocations to terrestrial services, the future refinement of the radio regulations above 40 GHz, and allocations of WARC-79 and frequency management.

  3. The structure and band gap design of high Si doping level Ag1-xGa1-xSixSe2 (x=1/2)

    NASA Astrophysics Data System (ADS)

    Zhang, Shiyan; Mei, Dajiang; Du, Xin; Lin, Zheshuai; Zhong, Junbo; Wu, Yuandong; Xu, Jingli

    2016-06-01

    Ag1-xGa1-xSixSe2 solutions with high Si doping level (x=1/2) are considered and new compound AgGaSiSe4 has been synthesized. It crystallizes in space group Aea2 and possesses very long axis of a=63.06(1)Å. The three-dimensional framework in AgGaSiSe4 is composed of AgSe3 trigonal planar units, AgSe4 tetrahedra and MSe4(M=Si, Ga) tetrahedra. AgGaSiSe4 is a congruently melting compound with the melt temperature of 759 °C. The diffuse reflectance measurements reveal the band gap of 2.63 eV in AgGaSiSe4 and the value is 0.33 eV larger than that of Ag3Ga3SiSe8 (2.30 eV).

  4. 30 GHz Commercial Satellite Receivers

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Ponchak, George E.; Romanofsky, Robert R.

    1989-01-01

    NASA's research and development work in satellite communications for the past 10 years has included a major technology thrust aimed at opening the Ka frequency band to commercial exploitation. This has included the development and testing of advanced system network architectures, on-board switching and processing, multibeam and phased array antennas, and satellite and ground terminal RF and digital hardware. Development work in system hardware has focused on critical components including power amplifiers, satellite IF switch matrices, low noise receivers, baseband processors, and high data rate bandwidth efficient modems. This paper describes NASA's work in developing and testing 30 GHz low noise satellite receivers for commercial space communications uplink applications. Frequencies allotted for fixed service commercial satellite communications in the Ka band are 27.5 - 30.0 GHz for uplink transmission and 17.7 - 20.2 GHz for downlink transmission. The relatively large 2.5 GHz bandwidth lends itself to wideband, high data rate digital transmission applications.

  5. 338-GHz Semiconductor Amplifier Module

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene A.; Gaier, Todd C.; Soria, Mary M.; Fung, King Man; Rasisic, Vesna; Deal, William; Leong, Kevin; Mei, Xiao Bing; Yoshida, Wayne; Liu, Po-Hsin; Uyeda, Jansen; Lai, Richard

    2010-01-01

    Research findings were reported from an investigation of new gallium nitride (GaN) monolithic millimeter-wave integrated circuit (MMIC) power amplifiers (PAs) targeting the highest output power and the highest efficiency for class-A operation in W-band (75-110 GHz). W-band PAs are a major component of many frequency multiplied submillimeter-wave LO signal sources. For spectrometer arrays, substantial W-band power is required due to the passive lossy frequency multipliers.

  6. Record-high and robust 17.125 Gb/s gross-rate over 25 km SSMF transmissions of real-time dual-band optical OFDM signals directly modulated by 1 GHz RSOAs.

    PubMed

    Zhang, Q W; Hugues-Salas, E; Ling, Y; Zhang, H B; Giddings, R P; Zhang, J J; Wang, M; Tang, J M

    2014-03-24

    Aggregated 17.125 Gb/s real-time end-to-end dual-band optical OFDM (OOFDM) transmissions over 25 km SSMF IMDD systems with 7 dB receiver sensitivity improvements are experimentally demonstrated, for the first time, by utilizing low-cost transceiver components such as directly modulated 1GHz RSOAs and DACs/ADCs operating at sampling speeds as low as 4GS/s. The demonstrated OOFDM transceivers have both strong adaptability and sufficiently large passband carrier frequency tunability, which enable full use of highly dynamic spectral characteristics of the transmission systems. This results in the achievements of not only excellent performance robustness to variations in system operating conditions but also significantly relaxed requirements on RSOA small-signal modulation bandwidth. It is shown that the aforementioned transmission capacity only varies by <23% over a RSOA-injected optical power variation range as large as 20dB, and that the 1 GHz RSOAs can support successful transmissions of adaptively modulated OOFDM signals having bandwidths of 8.5 GHz. By taking into account the adopted 25% cyclic prefix and a typical 7.3% FEC overhead, the demonstrated real-time OOFDM transmission systems are capable of conveying 11.6 Gb/s user data. PMID:24663982

  7. 47 CFR 101.525 - 24 GHz system operations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false 24 GHz system operations. 101.525 Section 101... FIXED MICROWAVE SERVICES 24 GHz Service and Digital Electronic Message Service § 101.525 24 GHz system operations. (a) A licensee using the 24 GHz band may construct and operate any number of fixed...

  8. Enhanced Microwave Absorption of SiO2-Coated Fe0.65Co0.35 Flakes at a Wide Frequency Band (1-18 GHz)

    NASA Astrophysics Data System (ADS)

    Luo, Hui; Gong, Rongzhou; Wang, Xian; Song, Kai; Chen, Yajie; Harris, Vincent G.

    2016-07-01

    Fe0.65Co0.35 (Fe-35Co) flakes were coated with SiO2 by the Stober process. The complex permittivity and permeability of both Fe-35Co and Fe-35Co/SiO2 composites were investigated over the frequency range of 1-18 GHz. Two dielectric resonance peaks were found in the Fe-35Co/SiO2 composite. Magnetic loss was verified to arise predominately from the natural resonance. Of particular importance is the natural resonance frequency increases with the SiO2 cladding. The experiments indicated that a reflection loss (RL) less than -20 dB for the Fe-35Co/SiO2 composites can be measured over the frequency range of 5.16-10.6 GHz with an absorbing thickness of 2-3.5 mm. Furthermore, an optimal RL of -60.23 dB was observed at 6.27 GHz with a thickness of 2.93 mm. The results provide a valuable path towards realizing microwave absorption over a wide frequency range.

  9. Enhanced Microwave Absorption of SiO2-Coated Fe0.65Co0.35 Flakes at a Wide Frequency Band (1-18 GHz)

    NASA Astrophysics Data System (ADS)

    Luo, Hui; Gong, Rongzhou; Wang, Xian; Song, Kai; Chen, Yajie; Harris, Vincent G.

    2016-05-01

    Fe0.65Co0.35 (Fe-35Co) flakes were coated with SiO2 by the Stober process. The complex permittivity and permeability of both Fe-35Co and Fe-35Co/SiO2 composites were investigated over the frequency range of 1-18 GHz. Two dielectric resonance peaks were found in the Fe-35Co/SiO2 composite. Magnetic loss was verified to arise predominately from the natural resonance. Of particular importance is the natural resonance frequency increases with the SiO2 cladding. The experiments indicated that a reflection loss (RL) less than -20 dB for the Fe-35Co/SiO2 composites can be measured over the frequency range of 5.16-10.6 GHz with an absorbing thickness of 2-3.5 mm. Furthermore, an optimal RL of -60.23 dB was observed at 6.27 GHz with a thickness of 2.93 mm. The results provide a valuable path towards realizing microwave absorption over a wide frequency range.

  10. X-Band/Ka-Band Dichroic Plate

    NASA Technical Reports Server (NTRS)

    Chen, Jacqueline C.

    1993-01-01

    Dichroic plate designed nearly transparent to circularly polarized microwaves at frequencies between 31.8 and 34.7 GHz (in and near Ka band) and reflective at frequencies between 8.4 and 8.5 GHz (in the X band). Made of electrically conductive material and contains rectangular holes in staggered pattern.

  11. Reducing flicker noise up-conversion in a 65nm CMOS VCO in the 1.6 to 2.6 GHz band

    NASA Astrophysics Data System (ADS)

    Pepe, Federico; Bonfanti, Andrea; Levantino, Salvatore; Samori, Carlo; Lacaita, Andrea Leonardo

    2013-05-01

    The demand of voltage-controlled oscillators (VCOs) with a broad tuning range can lead to unacceptable degradation of the 1/f3 phase-noise component if traditional voltage-biased topologies are implemented. In this paper, a novel VCO architecture is proposed, where a segmented transconductor tailors the negative-gm depending on the operating range to ensure that flicker noise up-conversion remains minimal. The implemented oscillator covers both 4G and WiMAX 2.5-GHz operation modes and achieves a 10-dB reduction of the 1/f3 phase noise without impairing the 1/f2 phase-noise performance.

  12. 2-GHz band CW and W-CDMA modulated radiofrequency fields have no significant effect on cell proliferation and gene expression profile in human cells.

    PubMed

    Sekijima, Masaru; Takeda, Hiroshi; Yasunaga, Katsuaki; Sakuma, Noriko; Hirose, Hideki; Nojima, Toshio; Miyakoshi, Junji

    2010-01-01

    We investigated the mechanisms by which radiofrequency (RF) fields exert their activity, and the changes in both cell proliferation and the gene expression profile in the human cell lines, A172 (glioblastoma), H4 (neuroglioma), and IMR-90 (fibroblasts from normal fetal lung) following exposure to 2.1425 GHz continuous wave (CW) and Wideband Code Division Multiple Access (W-CDMA) RF fields at three field levels. During the incubation phase, cells were exposed at the specific absorption rates (SARs) of 80, 250, or 800 mW/kg with both CW and W-CDMA RF fields for up to 96 h. Heat shock treatment was used as the positive control. No significant differences in cell growth or viability were observed between any test group exposed to W-CDMA or CW radiation and the sham-exposed negative controls. Using the Affymetrix Human Genome Array, only a very small (< 1%) number of available genes (ca. 16,000 to 19,000) exhibited altered expression in each experiment. The results confirm that low-level exposure to 2.1425 GHz CW and W-CDMA RF fields for up to 96 h did not act as an acute cytotoxicant in either cell proliferation or the gene expression profile. These results suggest that RF exposure up to the limit of whole-body average SAR levels as specified in the ICNIRP guidelines is unlikely to elicit a general stress response in the tested cell lines under these conditions. PMID:20215713

  13. MMIC Amplifiers for 90 to 130 GHz

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene; Pukala, David; Peralta, Alejandro; Bryerton, Eric; Morgan, Matt; Boyd, T.; Hu, Ming; Schmitz, Adele

    2007-01-01

    This brief describes two monolithic microwave integrated-circuit (MMIC) amplifier chips optimized to function in the frequency range of 90 to 130 GHz, covering nearly all of F-band (90 - 140 GHz). These amplifiers were designed specifically for local-oscillator units in astronomical radio telescopes such as the Atacama Large Millimeter Array (ALMA). They could also be readily adapted for use in electronic test equipment, automotive radar systems, and communications systems that operate between 90 and 130 GHz.

  14. A 20-GHz IMPATT transmitter

    NASA Technical Reports Server (NTRS)

    Chan, J. L.; Sun, C.

    1983-01-01

    The engineering development of a solid state transmitter amplifier operating in the 20 GHz frequency band. The development effort involved a variety of disciplines including IMPATT device development, circulator design, simple and multiple diode circuits designs, and amplifier integration and test.

  15. 47 CFR 25.258 - Sharing between NGSO MSS Feeder links Stations and GSO FSS services in the 29.25-29.5 GHz Bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    .... (a) Operators of NGSO MSS feeder link earth stations and GSO FSS earth stations in the band 29.25 to... MSS feeder link earth station complexes, that will minimize instances of unacceptable interference to the GSO FSS space stations. Earth station licensees operating with GSO FSS systems shall be capable...

  16. 47 CFR 25.258 - Sharing between NGSO MSS Feeder links Stations and GSO FSS services in the 29.25-29.5 GHz Bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    .... (a) Operators of NGSO MSS feeder link earth stations and GSO FSS earth stations in the band 29.25 to... MSS feeder link earth station complexes, that will minimize instances of unacceptable interference to the GSO FSS space stations. Earth station licensees operating with GSO FSS systems shall be capable...

  17. 47 CFR 25.258 - Sharing between NGSO MSS Feeder links Stations and GSO FSS services in the 29.25-29.5 GHz Bands.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .... (a) Operators of NGSO MSS feeder link earth stations and GSO FSS earth stations in the band 29.25 to... MSS feeder link earth station complexes, that will minimize instances of unacceptable interference to the GSO FSS space stations. Earth station licensees operating with GSO FSS systems shall be capable...

  18. 47 CFR 25.258 - Sharing between NGSO MSS Feeder links Stations and GSO FSS services in the 29.25-29.5 GHz Bands.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... (a) Operators of NGSO MSS feeder link earth stations and GSO FSS earth stations in the band 29.25 to... MSS feeder link earth station complexes, that will minimize instances of unacceptable interference to the GSO FSS space stations. Earth station licensees operating with GSO FSS systems shall be capable...

  19. 47 CFR 25.258 - Sharing between NGSO MSS Feeder links Stations and GSO FSS services in the 29.25-29.5 GHz Bands.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .... (a) Operators of NGSO MSS feeder link earth stations and GSO FSS earth stations in the band 29.25 to... MSS feeder link earth station complexes, that will minimize instances of unacceptable interference to the GSO FSS space stations. Earth station licensees operating with GSO FSS systems shall be capable...

  20. Design concepts for a high-impedance narrow-band 42 GHz power TWT using a fundamental/forward ladder-based circuit

    NASA Technical Reports Server (NTRS)

    Karp, A.

    1980-01-01

    A low-cost, narrowband, millimeter wave space communications TWT design was studied. Cold test interaction structure scale models were investigated and analyses were undertaken to predict the electrical and thermal response of the hypothetical 200 W TWT at 42 GHz and 21 kV beam voltage. An intentionally narrow instantaneous bandwidth (1%, with the possibility of electronic tuning of the center frequency over several percent) was sought with a highly dispersive, high impedance "forward wave' interaction structure based on a ladder (for economy in fabrication) and nonspace harmonic interaction, for a high gain rate and a short, economically focused tube. The "TunneLadder' interaction structure devised combines ladder properties with accommodation for a pencil beam. Except for the impedance and bandwidth, there is much in common with the millimeter wave helix TWTs which provided the ideal of diamond support rods. The benefits of these are enhanced in the TunneLadder case because of spatial separation of beam interception and RF current heating.

  1. Start-up scenario of a high-power pulsed gyrotron for 300 GHz band collective Thomson scattering diagnostics in the large helical device

    NASA Astrophysics Data System (ADS)

    Dumbrajs, O.; Saito, T.; Tatematsu, Y.

    2016-02-01

    We present results of theoretical study of mode competition during the voltage rise of a 300-kW, 300-GHz gyrotron operating in the TE22,2,1 mode. Simulations tracking eight competing modes show that, with a proper choice of the magnetic field, stable excitation of the operating mode can be realized, despite the presence of parasitic modes in the resonator spectrum. A finite voltage rise time, 1 kV/4 ns referred to as the slow voltage rise case, is taken into account to simulate realistically the experimental condition. Simulation results with the finite voltage rise time are in good agreement with the experimental test, in which the gyrotron demonstrated reliable operation at power levels up to 300 kW. Moreover, interesting phenomena are observed. Along with voltage rise, the oscillation manner changes from backward wave oscillation to gyrotron oscillation. In the range of the magnetic field lower than the magnetic field strength at which the TE22,2 mode attains to the maximum power, mode competition with the TE21,2 mode takes place although many other competing modes exist in between the two modes. In addition to the slow voltage rise case, the fast voltage rise case, 10 kV/4 ns, and the instant voltage rise case are considered. For these cases, simulations also predict stable oscillation of the TE22,2 mode with the same power level with the slow voltage rise case. This indicates that stable oscillations of the TE22,2 mode can be obtained in a wide range of the voltage rise time.

  2. Cryogenic testing of the 2.1 GHz five-cell superconducting RF cavity with a photonic band gap coupler cell

    NASA Astrophysics Data System (ADS)

    Arsenyev, Sergey A.; Temkin, Richard J.; Haynes, W. Brian; Shchegolkov, Dmitry Yu.; Simakov, Evgenya I.; Tajima, Tsuyoshi; Boulware, Chase H.; Grimm, Terrence L.; Rogacki, Adam R.

    2016-05-01

    We present results from cryogenic tests of the multi-cell superconducting radio frequency (SRF) cavity with a photonic band gap (PBG) coupler cell. Achieving high average beam currents is particularly desirable for future light sources and particle colliders based on SRF energy-recovery-linacs (ERLs). Beam current in ERLs is limited by the beam break-up instability, caused by parasitic higher order modes (HOMs) interacting with the beam in accelerating cavities. A PBG cell incorporated in an accelerating cavity can reduce the negative effect of HOMs by providing a frequency selective damping mechanism, thus allowing significantly higher beam currents. The multi-cell cavity was designed and fabricated of niobium. Two cryogenic (vertical) tests were conducted. The high unloaded Q-factor was demonstrated at a temperature of 4.2 K at accelerating gradients up to 3 MV/m. The measured value of the unloaded Q-factor was 1.55 × 108, in agreement with prediction.

  3. 20 GHz high power onboard beam switching circuit for multi-beam satellite systems

    NASA Astrophysics Data System (ADS)

    Araki, K.; Tanaka, T.

    A newly developed K-band beam switching circuit is presented. The K-band beam switching circuit for multibeam satellite system is effective to improve the transponder utilization efficiency. The beam switching circuit divides the output of a transponder among several different light traffic beams in a time division manner. The single pole double throw (SPDT) beam switching circuit consists of one circulator, one 90 degree hybrid coupler, and two 0/pi reflection type PIN diode phase shifters. A trially manufactured SPDT switching circuit has high power handling capability of more than 10 watts, low insertion loss of less than 1.2 dB, high isolation of more than 23 dB, and high speed switching time of faster than 100 nanoseconds in the frequency band between 18.85 GHz and 19.15 GHz.

  4. First Results from an Airborne Ka-Band SAR Using SweepSAR and Digital Beamforming

    NASA Technical Reports Server (NTRS)

    Sadowy, Gregory A.; Ghaemi, Hirad; Hensley, Scott C.

    2012-01-01

    SweepSAR is a wide-swath synthetic aperture radar technique that is being studied for application on the future Earth science radar missions. This paper describes the design of an airborne radar demonstration that simulates an 11-m L-band (1.2-1.3 GHz) reflector geometry at Ka-band (35.6 GHz) using a 40-cm reflector. The Ka-band SweepSAR Demonstration system was flown on the NASA DC-8 airborne laboratory and used to study engineering performance trades and array calibration for SweepSAR configurations. We present an instrument and experiment overview, instrument calibration and first results.

  5. Full-duplex fiber-wireless link for alternative wired and 40-GHz band wireless access based on differential quaternary phase-shift optical single sideband millimeter-wave signal

    NASA Astrophysics Data System (ADS)

    Zhang, Ruijiao; Ma, Jianxin; Xin, Xiangjun

    2015-02-01

    A full-duplex fiber-wireless link with a uniform single sideband differential quaternary phase-shift keying optical millimeter-wave signal is proposed to provide wired or 40-GHz band wireless access alternatively. The uniform optical millimeter-wave signal that supports services for wired or wireless users is produced via an LiNbO3 Mach-Zehnder modulator. After being transmitted to the hybrid optical network unit (HONU), it can be demodulated in different patterns on the demand of the user terminals for wired or wireless access. Simultaneously, part of the blank optical carrier abstracted from it is reused as the uplink optical carrier, so the HONU is free from the laser source, and thus, the complexity and cost of the system are reduced. Moreover, since the two tones of the dual-tone optical millimeter wave come from the same source, they maintain high coherency even after being transmitted over fiber. Additionally, the downlink data are carried by one tone of the dual-tone optical millimeter wave, so the downlink optical millimeter-wave signal suffers little from the fiber chromatic dispersion and laser phase noise. The theoretical analysis and simulation results show that our proposed full-duplex link for alternative wired and wireless access maintains good performance even when the transmission link with standard single mode fiber is extended to 30 km.

  6. 47 CFR 25.139 - NGSO FSS coordination and information sharing between MVDDS licensees in the 12.2 GHz to 12.7 GHz...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ....2 GHz to 12.7 GHz band. (a) NGSO FSS licensees shall maintain a subscriber database in a format that... database to enable the MVDDS licensee to determine whether the proposed MVDDS transmitting site meets...

  7. 47 CFR 25.139 - NGSO FSS coordination and information sharing between MVDDS licensees in the 12.2 GHz to 12.7 GHz...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ....2 GHz to 12.7 GHz band. (a) NGSO FSS licensees shall maintain a subscriber database in a format that... database to enable the MVDDS licensee to determine whether the proposed MVDDS transmitting site meets...

  8. 47 CFR 25.139 - NGSO FSS coordination and information sharing between MVDDS licensees in the 12.2 GHz to 12.7 GHz...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ....2 GHz to 12.7 GHz band. (a) NGSO FSS licensees shall maintain a subscriber database in a format that... database to enable the MVDDS licensee to determine whether the proposed MVDDS transmitting site meets...

  9. 47 CFR 25.139 - NGSO FSS coordination and information sharing between MVDDS licensees in the 12.2 GHz to 12.7 GHz...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ....2 GHz to 12.7 GHz band. (a) NGSO FSS licensees shall maintain a subscriber database in a format that... database to enable the MVDDS licensee to determine whether the proposed MVDDS transmitting site meets...

  10. 47 CFR 25.139 - NGSO FSS coordination and information sharing between MVDDS licensees in the 12.2 GHz to 12.7 GHz...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ....2 GHz to 12.7 GHz band. (a) NGSO FSS licensees shall maintain a subscriber database in a format that... database to enable the MVDDS licensee to determine whether the proposed MVDDS transmitting site meets...

  11. Two compact preamps cover 38-GHz bandwidth

    NASA Astrophysics Data System (ADS)

    Osbrink, N. K.; Fake, S. R.; Rosenberg, J. C.

    1985-09-01

    The design and performance characteristics of two compact preamplifiers that provide complete coverage of the 2-18 and 18-40 GHz frequency bands are examined. The 2-18-GHz prototype amplifier consists of four stages of thin-film hybrid microwave integrated circuit (MIC) amplification modules each of which incorporates a single GaAs distributed microwave integrated circuit (MMIC). The amplifier weights about 2 ounces and measures 1.75 x 1.15 x 0.67 inches. The 18-40-GHz amplifier consists of five thin-film MIC balanced gain stages and a MIC voltage regulator module with a throughline. The amplifier displays worst-case noise figures of 11.6 dB at the low frequency end of the band and less than 8 dB over much of the band.

  12. Sixty GHz IMPATT diode development

    NASA Technical Reports Server (NTRS)

    Ma, Y. E.; Chen, J.; Benko, E.; Barger, M. J.; Nghiem, H.; Trinh, T. Q.; Kung, J.

    1985-01-01

    The objective of this program is to develop 60 GHz GaAs IMPATT Diodes suitable for communications applications. The performance goal of the 60 GHz IMPATT is 1W CW output power with a conversion efficiency of 15 percent and 10 year life time. During the course of the program, double drift (DD) GaAs IMPATT Diodes have been developed resulting in the state of the art performance at V band frequencies. A CW output power of 1.12 W was demonstrated at 51.9 GHz with 9.7 percent efficiency. The best conversion efficiency achieved was 15.3 percent. V band DD GaAs IMPATTs were developed using both small signal and large signal analyses. GaAs wafers of DD flat, DD hybrid, and DD Read profiles using molecular beam epitaxy (MBE) were developed with excellent doping profile control. Wafer evaluation was routinely made by the capacitance versus voltage (C-V) measurement. Ion mass spectrometry (SIMS) analysis was also used for more detailed profile evaluation.

  13. Using a 1.2 GHz bandwidth reflective semiconductor optical amplifier with seeding light by 64-quadrature amplitude modulation orthogonal frequency division multiplexing modulation to achieve a 10-gbits/s upstream rate in long-reach passive optical network access

    NASA Astrophysics Data System (ADS)

    Yeh, Chien-Hung; Chen, Hsing-Yu; Chow, Chi-Wai; Wu, Yu-Fu

    2012-01-01

    We use a commercially available 1.2 GHz bandwidth reflective semiconductor optical amplifier (RSOA)--based optical network unit (ONU) to achieve 10-gbits/s upstream traffic for an optical orthogonal frequency division multiplexing (OFDM) long-reach passive optical network (LR-PON). This is the first time the 64--quadrature amplitude modulation (QAM) OFDM format has been applied to RSOA-ONU to achieve a 75 km fiber transmission length. In the proposed LR-PON, the upstream power penalty of 5.2 dB at the bit error rate of 3.8×10-3 is measured by using a 64-QAM OFDM modulation after the 75 km fiber transmission without dispersion compensation.

  14. Tree attenuation at 20 GHz: Foliage effects

    NASA Astrophysics Data System (ADS)

    Vogel, Wolfhard J.; Goldhirsh, Julius

    1993-08-01

    Static tree attenuation measurements at 20 GHz (K-Band) on a 30 deg slant path through a mature Pecan tree with and without leaves showed median fades exceeding approximately 23 dB and 7 dB, respectively. The corresponding 1% probability fades were 43 dB and 25 dB. Previous 1.6 GHz (L-Band) measurements for the bare tree case showed fades larger than those at K-Band by 3.4 dB for the median and smaller by approximately 7 dB at the 1% probability. While the presence of foliage had only a small effect on fading at L-Band (approximately 1 dB additional for the median to 1% probability range), the attenuation increase was significant at K-Band, where it increased by about 17 dB over the same probability range.

  15. Tree attenuation at 20 GHz: Foliage effects

    NASA Technical Reports Server (NTRS)

    Vogel, Wolfhard J.; Goldhirsh, Julius

    1993-01-01

    Static tree attenuation measurements at 20 GHz (K-Band) on a 30 deg slant path through a mature Pecan tree with and without leaves showed median fades exceeding approximately 23 dB and 7 dB, respectively. The corresponding 1% probability fades were 43 dB and 25 dB. Previous 1.6 GHz (L-Band) measurements for the bare tree case showed fades larger than those at K-Band by 3.4 dB for the median and smaller by approximately 7 dB at the 1% probability. While the presence of foliage had only a small effect on fading at L-Band (approximately 1 dB additional for the median to 1% probability range), the attenuation increase was significant at K-Band, where it increased by about 17 dB over the same probability range.

  16. Atmospheric sounding near 118 GHz

    NASA Technical Reports Server (NTRS)

    Ali, A. D. S.; Rosenkranz, P. W.; Staelin, D. H.

    1980-01-01

    The thermal emission spectrum of the atmosphere near the 118 GHz oxygen resonance has been measured from the NASA Convair-990 aircraft as it flew over clear air and storms. The instrument viewed the ground 45 deg from nadir with a 7.5 deg beamwidth. Brightness temperatures were measured in six bands 200 MHz wide centered at frequencies 821-1891 MHz from the line at 118.7505 GHz. The double-sideband super-heterodyne receiver had 1 K sensitivity for 1 s integration. Comparison of observed clear air brightness temperatures (from 238 mb) with those computed for a coincident dropsonde yielded agreement within 1.4 K; the retrieved temperature profile agreed with the dropsonde with an average magnitude error of 1.4 K.

  17. Cryogenic 160-GHz MMIC Heterodyne Receiver Module

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene A.; Soria, Mary M.; Owen, Heather R.; Dawson, Douglas E.; Kangaslahti, Pekka P.; Gaier, Todd C.; Voll, Patricia; Lau, Judy; Sieth, Matt; Church, Sarah

    2011-01-01

    A cryogenic 160-GHz MMIC heterodyne receiver module has demonstrated a system noise temperature of 100 K or less at 166 GHz. This module builds upon work previously described in Development of a 150-GHz MMIC Module Prototype for Large-Scale CMB Radiation (NPO-47664), NASA Tech Briefs, Vol. 35, No. 8 (August 2011), p. 27. In the original module, the local oscillator signal was saturating the MMIC low-noise amplifiers (LNAs) with power. In order to suppress the local oscillator signal from reaching the MMIC LNAs, the W-band (75 110 GHz) signal had to be filtered out before reaching 140 170 GHz. A bandpass filter was developed to cover 120 170 GHz, using microstrip parallel-coupled lines to achieve the desired filter bandwidth, and ensure that the unwanted W-band local oscillator signal would be sufficiently suppressed. With the new bandpass filter, the entire receiver can work over the 140 180-GHz band, with a minimum system noise temperature of 460 K at 166 GHz. The module was tested cryogenically at 20 K ambient temperature, and it was found that the receiver had a noise temperature of 100 K over an 8-GHz bandwidth. The receiver module now includes a microstrip bandpass filter, which was designed to have a 3-dB bandwidth of approximately 120-170 GHz. The filter was fabricated on a 3-mil-thick alumina substrate. The filter design was based on a W-band filter design made at JPL and used in the QUIET (Q/U Imaging ExperimenT) radiometer modules. The W-band filter was scaled for a new center frequency of 150 GHz, and the microstrip segments were changed accordingly. Also, to decrease the bandwidth of the resulting scaled design, the center gaps between the microstrip lines were increased (by four micrometers in length) compared to the gaps near the edges. The use of the 150-GHz bandpass filter has enabled the receiver module to function well at room temperature. The system noise temperature was measured to be less than 600 K (at room temperature) from 154 to 168 GHz

  18. An integrated membrane sub-harmonic Schottky diode mixers at 340GHz

    NASA Astrophysics Data System (ADS)

    Wang, Junlong; Yang, Dabao; Xing, Dong; Liang, Shixiong; Zhang, Lisen; Zhao, Xiangyang; Feng, Zhihong

    2015-11-01

    This paper presents a sub-harmonic mixer operating over the spectral band 332-348 GHz. The mixers employ integrated GaAs membrane Schottky diode technology. The simulated results show that the conversion loss of the mixer is below dB in the band from 333 GHz to 347 GHz with a local oscillator power requirement of 5mW.The minimum is 8.2dB at 344GHz.

  19. 183-GHz Radiometer Handbook - November 2006

    SciTech Connect

    MP Cadeddu

    2006-11-30

    The G-Band Vapor Radiometer (GVR) provides time-series measurements of brightness temperatures from four double sideband channels centered at ± 1, ± 3, ± 7, and ± 14 GHz around the 183.31-GHz water vapor line. Atmospheric emission in this spectral region is primarily due to water vapor, with some influence from liquid water. The 183.31 ± 14-GHz channel is particularly sensitive to the presence of liquid water. The sensitivity to water vapor of the 183.31-GHz line is approximately 30 times higher than at the frequencies of the two-channel microwave radiometer (MWR) for a precipitable water vapor (PWV) amount of less than 2.5 mm. Measurements from this nstrument are therefore especially useful during low-humidity conditions (PWV < 5 mm).

  20. Structural phase transition, narrow band gap, and room-temperature ferromagnetism in [KNbO{sub 3}]{sub 1−x}[BaNi{sub 1/2}Nb{sub 1/2}O{sub 3−δ}]{sub x} ferroelectrics

    SciTech Connect

    Zhou, Wenliang; Yang, Pingxiong Chu, Junhao; Deng, Hongmei

    2014-09-15

    Structural phase transition, narrow band gap (E{sub g}), and room-temperature ferromagnetism (RTFM) have been observed in the [KNbO{sub 3}]{sub 1−x}[BaNi{sub 1/2}Nb{sub 1/2}O{sub 3−δ}]{sub x} (KBNNO) ceramics. All the samples have single phase perovskite structure, but exhibit a gradual transition behaviour from the orthorhombic to a cubic structure with the increase of x. Raman spectroscopy analysis not only corroborates this doping-induced change in normal structure but also shows the local crystal symmetry for x ≥ 0.1 compositions to deviate from the idealized cubic perovskite structure. A possible mechanism for the observed specific changes in lattice structure is discussed. Moreover, it is noted that KBNNO with compositions x = 0.1–0.3 have quite narrow E{sub g} of below 1.5 eV, much smaller than the 3.2 eV band gap of parent KNbO{sub 3} (KNO), which is due to the increasing Ni 3d electronic states within the gap of KNO. Furthermore, the KBNNO materials present RTFM near a tetragonal to cubic phase boundary. With increasing x from 0 to 0.3, the magnetism of the samples develops from diamagnetism to ferromagnetism and paramagnetism, originating from the ferromagnetic–antiferromagnetic competition. These results are helpful in the deeper understanding of phase transitions, band gap tunability, and magnetism variations in perovskite oxides and show the potential role, such materials can play, in perovskite solar cells and multiferroic applications.

  1. Cosmic Microwave Background Observations with a Compact Heterogeneous 150 GHz Interferometer in Chile

    NASA Astrophysics Data System (ADS)

    Fowler, J. W.; Doriese, W. B.; Marriage, T. A.; Tran, H. T.; Aboobaker, A. M.; Dumont, C.; Halpern, M.; Kermish, Z. D.; Loh, Y.-S.; Page, L. A.; Staggs, S. T.; Wesley, D. H.

    2005-01-01

    We report on the design, first observing season, and analysis of data from a new prototype millimeter-wave interferometer, MINT. MINT consists of four 145 GHz SIS mixers operating in double-sideband mode in a compact heterogeneous configuration. The signal band is subdivided by a monolithic channelizer, after which the correlations between antennas are performed digitally. The typical receiver sensitivity in a 2 GHz band is 1.4 mK s1/2. The primary beams are 0.45d and 0.30d FWHM, with fringe spacing as small as 0.1d. MINT observed the cosmic microwave background (CMB) from Cerro Toco, in the Chilean Altiplano. The site quality at 145 GHz is good, with median nighttime atmospheric temperature of 9 K at zenith (exclusive of the CMB). Repeated observations of Mars, Jupiter, and a telescope-mounted calibration source establish the phase and magnitude stability of the system. MINT is the first interferometer dedicated to CMB studies to operate above 50 GHz. The same type of system can be used to probe the Sunyaev-Zel'dovich effect in galaxy clusters near the SZ null at 217 GHz. We give the essential features of MINT and present an analysis of sideband-separated, digitally sampled data recorded by the array. Based on 215 hours of data taken in late 2001, we set an upper limit on the CMB anisotropy in a band of width Δl=700 around l=1540 of δT<105 μK (95% confidence). Increased sensitivity can be achieved with more integration time, greater bandwidth, and more elements.

  2. 47 CFR 25.287 - Requirements pertaining to operation of mobile stations in the NVNG, 1.5/1.6 GHz, 1.6/2.4 GHz...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... capabilities to ensure compliance with Footnote 5.353A in 47 CFR 2.106 and the priority and real-time... stations in the NVNG, 1.5/1.6 GHz, 1.6/2.4 GHz, and 2 GHz Mobile-Satellite Service bands. 25.287 Section 25.287 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES...

  3. High-performance Ka-band and V-band HEMT low-noise amplifiers

    NASA Technical Reports Server (NTRS)

    Duh, K. H. George; Chao, Pane-Chane; Smith, Phillip M.; Lester, Luke F.; Lee, Benjamin R.

    1988-01-01

    Quarter-micron-gate-length high-electron-mobility transistors (HEMTs) have exhibited state-of-the-art low-noise performance at millimeter-wave frequencies, with minimum noise figures of 1.2 dB at 32 GHz and 1.8 dB at 60 GHz. At Ka-band, two-stage and three-stage HEMT low noise amplifiers have demonstrated noise figures of 1.7 and 1.9 dB, respectively, with associated gains of 17.0 and 24.0 dB at 32 GHz. At V-band, two stage and three-stage HEMT amplifiers yielded noise figures of 3.2 and 3.6 dB, respectively, with associated gains of 12.7 and 20.0 dB at 60 GHz. The 1-dB-gain compression point of all the amplifiers is greater than +6 dBm. The results clearly show the potential of short-gate-length HEMTs for high-performance millimeter-wave receiver applications.

  4. Double dipole antenna SIS receivers at 100 and 400 GHz

    NASA Technical Reports Server (NTRS)

    Skalare, A.; Vandestadt, H.; Degraauw, T.; Panhuyzen, R. A.; Dierichs, M. M. T. M.

    1992-01-01

    Antenna patterns were measured between 95 and 120 GHz for a double dipole antenna / ellipsoidal lens combination. The structure produces a non-astigmatic beam with low side lobe levels over that whole band. A heterodyne SIS receiver based on this concept gave a best noise temperature of 145 K DSB at 98 GHz. Measurements were also made with a 400 GHz heterodyne SIS receiver, using a double dipole antenna in conjunction with a hyperhemispherical lens. The best noise temperature was 220 K DSB at 402 GHz. On-chip stubs were used to tune out the SIS junction capacitance.

  5. Lightweight Reflectarray Antenna for 7.115 and 32 GHz

    NASA Technical Reports Server (NTRS)

    Zawadzki, Mark; Huang, John

    2007-01-01

    A lightweight reflectarray antenna that would enable simultaneous operation at frequencies near 7.115 GHz and frequencies near 32 GHz is undergoing development. More precisely, what is being developed is a combination of two reflectarray antennas -- one for each frequency band -- that share the same aperture. (A single reflectarray cannot work in both frequency bands.) The main advantage of the single dual-band reflectarray is that it would weigh less and occupy less space than do two single-band reflectarray antennas

  6. The 60 GHz solid state power amplifier

    NASA Technical Reports Server (NTRS)

    Mcclymonds, J.

    1991-01-01

    A new amplifier architecture was developed during this contract that is superior to any other solid state approach. The amplifier produced 6 watts with 4 percent efficiency over a 2 GHz band at 61.5 GHz. The unit was 7 x 9 x 3 inches in size, 5.5 pounds in weight, and the conduction cooling through the baseplate is suitable for use in space. The amplifier used high efficiency GaAs IMPATT diodes which were mounted in 1-diode circuits, called modules. Eighteen modules were used in the design, and power combining was accomplished with a proprietary passive component called a combiner plate.

  7. The 30 GHz communications satellite low noise receiver

    NASA Astrophysics Data System (ADS)

    Steffek, L. J.; Smith, D. W.

    1983-10-01

    A Ka-band low noise front end in proof of concept (POC) model form for ultimate spaceborne communications receiver deployment was developed. The low noise receiver consists of a 27.5 to 30.0 GHz image enhanced mixer integrated with a 3.7 to 6.2 GHz FET low noise IF amplifier and driven by a self contained 23.8 GHz phase locked local oscillator source. The measured level of receiver performance over the 27.3 to 30.0 GHz RF/3.7 to 6.2 GHz IF band includes 5.5 to 6.5 dB (typ) SSB noise figure, 20.5 + or - 1.5 dB conversion gain and +23 dBm minimum third order two tone intermodulation output intercept point.

  8. The 30 GHz communications satellite low noise receiver

    NASA Technical Reports Server (NTRS)

    Steffek, L. J.; Smith, D. W.

    1983-01-01

    A Ka-band low noise front end in proof of concept (POC) model form for ultimate spaceborne communications receiver deployment was developed. The low noise receiver consists of a 27.5 to 30.0 GHz image enhanced mixer integrated with a 3.7 to 6.2 GHz FET low noise IF amplifier and driven by a self contained 23.8 GHz phase locked local oscillator source. The measured level of receiver performance over the 27.3 to 30.0 GHz RF/3.7 to 6.2 GHz IF band includes 5.5 to 6.5 dB (typ) SSB noise figure, 20.5 + or - 1.5 dB conversion gain and +23 dBm minimum third order two tone intermodulation output intercept point.

  9. 47 CFR 27.806 - 1.4 GHz service licenses subject to competitive bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false 1.4 GHz service licenses subject to competitive bidding. 27.806 Section 27.806 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1.4 GHz Band § 27.806 1.4 GHz...

  10. 47 CFR 27.806 - 1.4 GHz service licenses subject to competitive bidding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false 1.4 GHz service licenses subject to competitive bidding. 27.806 Section 27.806 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1.4 GHz Band § 27.806 1.4 GHz...

  11. Design of the 0.5 - 1 GHz Planar Recycler Pickup and Kicker Antennas

    SciTech Connect

    Deibele, C.; /Fermilab

    1999-01-01

    The stochastic cooling system in the Recycler ring at Fermilab required the addition of a 0.5-1 GHz cooling system. This requirement dictated the design of a new antenna for this band of the system. The design problem is defined, method of design is illustrated, and the measurement data are reported. The Recycler is a storage ring comprised of mostly permanent magnets located in the tunnel of the Main Injector at Fermilab. The goal for the construction of the Recycler is to collect and store unused antiprotons from collisions in the Tevatron for use in future collisions in the Tevatron. It will both stochastically and electron cool these unused antiprotons before another collision experiment is possible in the Tevatron. By reusing the antiprotons the luminosity of the experiment can be increased faster. The Recycler will use three bands for its stochastic cooling system. It will reuse the existing designs from the Antiproton Source for the 1-2 GHz and 2-4 GHz systems, and it requires a new design for an additional lower frequency band for the 0.5-1 GHz system. Since the existing designs were fabricated using a microstrip topology it was desired that the new design use a similar topology so that the vacuum tank designs and supporting hardware be identical for all three bands. A primary difference between the design of the pickups/kickers of the Antiproton Source and the Recycler is a different aperture in the machine itself. The Recycler has a bigger aperture and consequently reusing the designs for the existing Antiproton Source pickups/kickers is not electrically optimal but is cost efficient. Measurements will be shown later in this paper for the design of the 0.5-1 GHz system showing the effect of the aperture on the antenna performance. A mockup of the Recycler tank was manufactured for designing and testing the 0.5-1 GHz pickups/kickers. The design procedure was an iterative process and required both a constant dialogue and also a strong relationship with a

  12. Photon polarization version of the GHz-Mermin Gedanken

    NASA Technical Reports Server (NTRS)

    Kiess, Thomas E.

    1992-01-01

    We have defined a photon polarization analog of the Greenberger, Horne, and Zeilinger (GHZ) experiment that was initially proposed for spin-1/2 quanta. Analogs of the ket states and Pauli spin matrix operators are presented.

  13. Graphene based GHz detectors

    NASA Astrophysics Data System (ADS)

    Boyd, Anthony K.; El Fatimy, Abdel; Barbara, Paola; Nath, Anindya; Campbell, Paul M.; Myers-Ward, Rachael; Daniels, Kevin; Gaskill, D. Kurt

    Graphene demonstrates great promise as a detector over a wide spectral range especially in the GHz range. This is because absorption is enhanced due to the Drude contribution. In the GHz range there are viable detection mechanisms for graphene devices. With this in mind, two types of GHz detectors are fabricated on epitaxial graphene using a lift off resist-based clean lithography process to produce low contact resistance. Both device types use asymmetry for detection, consistent with recent thoughts of the photothermoelectric effect (PTE) mechanism. The first is an antenna coupled device. It utilizes two dissimilar contact metals and the work function difference produces the asymmetry. The other device is a field effect transistor constructed with an asymmetric top gate that creates a PN junction and facilitates tuning the photovoltaic response. The response of both device types, tested from 100GHz to 170GHz, are reported. This work was sponsored by the U.S. Office of Naval Research (Award Number N000141310865).

  14. Traveling-Wave Maser for 32 GHz

    NASA Technical Reports Server (NTRS)

    Shell, James; Clauss, Robert

    2009-01-01

    The figure depicts a traveling-wave ruby maser that has been designed (though not yet implemented in hardware) to serve as a low-noise amplifier for reception of weak radio signals in the frequency band of 31.8 to 32.3 GHz. The design offers significant improvements over previous designs of 32-GHz traveling-wave masers. In addition, relative to prior designs of 32-GHz amplifiers based on high-electron-mobility transistors, this design affords higher immunity to radio-frequency interference and lower equivalent input noise temperature. In addition to the basic frequency-band and low-noise requirements, the initial design problem included a requirement for capability of operation in a closed-cycle helium refrigerator at a temperature .4 K and a requirement that the design be mechanically simplified, relative to prior designs, in order to minimize the cost of fabrication and assembly. Previous attempts to build 32- GHz traveling-wave masers involved the use of metallic slow-wave structures comprising coupled transverse electromagnetic (TEM)-mode resonators that were subject to very tight tolerances and, hence, were expensive to fabricate and assemble. Impedance matching for coupling signals into and out of these earlier masers was very difficult. A key feature of the design is a slow-wave structure, the metallic portions of which would be mechanically relatively simple in that, unlike in prior slow-wave structures, there would be no internal metal steps, irises, or posts. The metallic portions of the slow-wave structure would consist only of two rectangular metal waveguide arms. The arms would contain sections filled with the active material (ruby) alternating with evanescent-wave sections. This structure would be transparent in both the signal-frequency band (the aforementioned range of 31.8 to 32.3 GHz) and the pump-frequency band (65.75 to 66.75 GHz), and would impose large slowing factors in both frequency bands. Resonant ferrite isolators would be placed in the

  15. Oriented 1,2-dimyristoyl-sn-glycero-3-phosphorylcholine/ganglioside membranes: a Fourier transform infrared attenuated total reflection spectroscopic study. Band assignments; orientational, hydrational, and phase behavior; and effects of Ca2+ binding.

    PubMed Central

    Müller, E; Giehl, A; Schwarzmann, G; Sandhoff, K; Blume, A

    1996-01-01

    Fourier transform infrared (FTIR) attenuated total reflection (ATR) spectroscopy was used to elucidate the hydration behavior and molecular order of phospholipid/ganglioside bilayers. We examined dry and hydrated films of the gangliosides GM1, deacetyl-GM1, lyso-GM1, deacetyllyso-GM1, and GM3 and oriented mixed films of these gangliosides with 1,2-dimyristoyl-sn-glycero-3-phosphorylcholine (DMPC) using polarized light. Analysis of the amide I frequencies reveals that the amide groups are involved in intermolecular interactions via hydrogen bonds of varying strengths. The tilt angle of the acyl chains of the lipids in mixed films was determined as a function of ganglioside structure. Deacetylation of the sialic acid in the headgroup has a stronger influence on the tilt angle than the removal of the ganglioside fatty acid. The phase behavior was examined by FTIR ATR spectroscopy and by differential scanning calorimetry (DSC) measurements on lipid suspensions. At the same molar concentration, lyso-gangliosides have less effect on changes of transition temperature compared to the double-chain analogs. Distinct differences in the amide band shapes were observed between mixtures with lyso-gangliosides and normal double-chain gangliosides. Determined from the dicroic ratio RATR, the orientation of the COO- group in all DMPC/ganglioside mixtures was found to be relatively fixed with respect to the membrane normal. In 4:1 mixtures of DMPC with GM1 and deacetyl-GM1, the binding of Ca2+ leads to a slight decrease in chain tilt in the gel phase, probably caused by a dehydration of the membrane-water interface. In mixtures of DMPC with GM3 and deacetyl-lyso-GM1, a slight increase in chain tilt is observed. The chain tilt in DMPC/lyso-GM1 mixtures is unchanged. Analysis of the COO- band reveals that Ca2+ does not bind to the carboxylate group of the sialic acid of GM1 and deacetyl-GM1, the mixtures in which a decrease in chain tilt was observed. Binding to the sialic acid was

  16. A broadband 47-67 GHz LNA with 17.3 dB gain in 65-nm CMOS

    NASA Astrophysics Data System (ADS)

    Chong, Wang; Zhiqun, Li; Qin, Li; Yang, Liu; Zhigong, Wang

    2015-10-01

    A broadband 47-67 GHz low noise amplifier (LNA) with 17.3 dB gain in 65-nm CMOS technology is proposed. The features of millimeter wave circuits are illustrated first and design methodologies are discussed. The wideband input matching of the LNA was achieved by source inductive degeneration, which is narrowband in the low-GHz range but wideband at millimeter-wave frequencies due to the existence of gate-drain capacitance, Cgd. In order to minimize the noise figure (NF), the LNA used a common-source (CS) structure rather than cascode in the first stage, and the noise matching principle is explored. The last two stages of the LNA used a cascode structure to increase the power gain. Analysis of the gain boost effect of the gate inductor at the common-gate (CG) transistor is also performed. T-shape matching networks between stages are intended to enlarge the bandwidth. All on-chip inductors and transmission lines are modeled and simulated with a 3-dimensional electromagnetic (EM) simulation tool to guarantee the success of the design. Measurement results show that the LNA achieves a maximum gain of 17.3 dB at 60 GHz, while the 3-dB bandwidth is 20 GHz (47-67 GHz), including the interested band of 59-64 GHz, and the minimum noise figure is 4.9 dB at 62 GHz. The LNA absorbs a current of 19 mA from a 1.2 V supply and the chip occupies an area of 900 × 550 μm2 including pads. Project supported by the National High Technology Research and Development Program of China (No. 2011AA010202).

  17. Dielectric measurements at 30-40 GHz and 140 GHz performed on the specimen set of the NPL intercomparison exercise

    NASA Astrophysics Data System (ADS)

    Heidinger, R.; Koeniger, F.

    1991-10-01

    Ceramic samples (BeO, Macor and quartz) and polymeric samples (Rexolite, polyethylene) are measured for a near millimeter wavelength specimen intercomparison task. The data is used to relate the results of recently established dielectric measuring facilities to results from different techniques. The Ka band (30 to 40 GHz) and D band (140 GHz) are covered by two different Fabry-Perot resonator setups. Data evaluation is discussed in detail and various correction procedures to sample thickness are tested. The results of both frequency bands coincide for most specimens. The lowest dielectric loss is found in single crystal quartz. The dielectric loss increases strongly with frequency in Rexolite only and slightly in Macor.

  18. 47 CFR 15.249 - Operation within the bands 902-928 MHz, 2400-2483.5 MHz, 5725-5875 MHZ, and 24.0-24.25 GHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits... emissions from intentional radiators operated within these frequency bands shall comply with the following..., and multiple co-located intentional radiators transmitting the same information are not allowed....

  19. 47 CFR 15.249 - Operation within the bands 902-928 MHz, 2400-2483.5 MHz, 5725-5875 MHZ, and 24.0-24.25 GHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits... emissions from intentional radiators operated within these frequency bands shall comply with the following..., and multiple co-located intentional radiators transmitting the same information are not allowed....

  20. 47 CFR 15.249 - Operation within the bands 902-928 MHz, 2400-2483.5 MHz, 5725-5875 MHZ, and 24.0-24.25 GHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits... emissions from intentional radiators operated within these frequency bands shall comply with the following..., and multiple co-located intentional radiators transmitting the same information are not allowed....

  1. 47 CFR 15.249 - Operation within the bands 902-928 MHz, 2400-2483.5 MHz, 5725-5875 MHZ, and 24.0-24.25 GHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits... emissions from intentional radiators operated within these frequency bands shall comply with the following..., and multiple co-located intentional radiators transmitting the same information are not allowed....

  2. 47 CFR 15.249 - Operation within the bands 902-928 MHz, 2400-2483.5 MHz, 5725-5875 MHZ, and 24.0-24.25 GHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits... emissions from intentional radiators operated within these frequency bands shall comply with the following..., and multiple co-located intentional radiators transmitting the same information are not allowed....

  3. 177-207 GHz Radiometer Front End: Single Sideband Measurements

    NASA Technical Reports Server (NTRS)

    Galin, I.; Schnitzer, C. A.; Dengler, R. J.; Quintero, O.

    1999-01-01

    Twenty years of progress in 200 GHz receivers for spaceborne remote sensing has yielded a 180-220 GHz technology with maturing characteristics, as evident by increasing availability of relevant hardware, paralleled by further refinement in receiver performance requirements at this spectrum band. The 177-207 GHz superheterodyne receiver, for the Earth observing system (EOS) microwave limb sounder (MLS), effectively illustrates such technology developments. This MLS receiver simultaneously detects six different signals, located at sidebands below and above its 191.95 GHZ local-oscillator (LO). The paper describes the MLS 177-207 GHz receiver front-end (RFE), and provides measured data for its lower and upper sidebands. Sideband ratio data is provided as a function of IF frequency, at different LO power drive, and for variation in the ambient temperature.

  4. RF performance measurement of the DSS-14 70-meter antenna at C-band/L-band

    NASA Technical Reports Server (NTRS)

    Gatti, M. S.; Freiley, A. J.; Girdner, D.

    1989-01-01

    The calibration of the 70-meter antenna at C-band (5.01 GHz) and L-band (1.668 GHz) is described. This calibration comes after a modification to an existing L-band feed to include the C-band frequencies. The test technique employs noise-adding radiometers and associated equipment running simultaneously at both frequencies. The test procedure is described including block diagrams, and results are presented for efficiency, system temperature, and pointing.

  5. X-SAR: The X-band synthetic aperture radar on board the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Werner, Marian U.

    1993-01-01

    The X-band synthetic aperture radar (X-SAR) is the German/Italian contribution to the NASA/JPL Shuttle Radar Lab missions as part of the preparation for the Earth Observation System (EOS) program. The Shuttle Radar Lab is a combination of several radars: an L-band (1.2 GHz) and a C-band (5.3 GHz) multipolarization SAR known as SIR-C (Shuttle Imaging Radar); and an X-band (9.6 GHz) vertically polarized SAR which will be operated synchronously over the same target areas to deliver calibrated multifrequency and multipolarization SAR data at multiple incidence angles from space. A joint German/Italian project office at DARA (German Space Agency) is responsible for the management of the X-SAR project. The space hardware has been developed and manufactured under industrial contract by Dornier and Alenia Spazio. Besides supporting all the technical and scientific tasks, DLR, in cooperation with ASI (Agencia Spaziale Italiano) is responsible for mission operation, calibration, and high precision SAR processing. In addition, DLR developed an airborne X-band SAR to support the experimenters with campaigns to prepare for the missions. The main advantage of adding a shorter wavelength (3 cm) radar to the SIR-C radars is the X-band radar's weaker penetration into vegetation and soil and its high sensitivity to surface roughness and associated phenomena. The performance of each of the three radars is comparable with respect to radiometric and geometric resolution.

  6. X-SAR: The X-band synthetic aperture radar on board the Space Shuttle

    NASA Astrophysics Data System (ADS)

    Werner, Marian U.

    1993-05-01

    The X-band synthetic aperture radar (X-SAR) is the German/Italian contribution to the NASA/JPL Shuttle Radar Lab missions as part of the preparation for the Earth Observation System (EOS) program. The Shuttle Radar Lab is a combination of several radars: an L-band (1.2 GHz) and a C-band (5.3 GHz) multipolarization SAR known as SIR-C (Shuttle Imaging Radar); and an X-band (9.6 GHz) vertically polarized SAR which will be operated synchronously over the same target areas to deliver calibrated multifrequency and multipolarization SAR data at multiple incidence angles from space. A joint German/Italian project office at DARA (German Space Agency) is responsible for the management of the X-SAR project. The space hardware has been developed and manufactured under industrial contract by Dornier and Alenia Spazio. Besides supporting all the technical and scientific tasks, DLR, in cooperation with ASI (Agencia Spaziale Italiano) is responsible for mission operation, calibration, and high precision SAR processing. In addition, DLR developed an airborne X-band SAR to support the experimenters with campaigns to prepare for the missions. The main advantage of adding a shorter wavelength (3 cm) radar to the SIR-C radars is the X-band radar's weaker penetration into vegetation and soil and its high sensitivity to surface roughness and associated phenomena. The performance of each of the three radars is comparable with respect to radiometric and geometric resolution.

  7. Saturation recovery EPR and ELDOR at W-band for spin labels

    PubMed Central

    Froncisz, Wojciech; Camenisch, Theodore G.; Ratke, Joseph J.; Anderson, James R.; Subczynski, Witold K.; Strangeway, Robert A.; Sidabras, Jason W.; Hyde, James S.

    2008-01-01

    A reference-arm W-band (94 GHz) microwave bridge with two sample-irradiation arms for saturation recovery (SR) EPR and ELDOR experiments is described. Frequencies in each arm are derived from 2 GHz synthesizers that have a common time-base and are translated to 94 GHz in steps of 33 and 59 GHz. Intended applications are to nitroxide radical spin labels and spin probes in the liquid phase. An enabling technology is the use of a W-band loop-gap resonator (LGR) (J.W. Sidabras et al., Rev. Sci. Instrum. 78 (2007) 034701). The high efficiency parameter (8.2 GW−1/2 with sample) permits the saturating pump pulse level to be just 5 mW or less. Applications of SR EPR and ELDOR to the hydrophilic spin labels 3-carbamoyl-2,2,5,5-tetra-methyl-3-pyrroline-1-yloxyl (CTPO) and 2,2,6,6,-tetramethyl-4-piperidone-1-oxyl (TEMPONE) are described in detail. In the SR ELDOR experiment, nitrogen nuclear relaxation as well as Heisenberg exchange transfer saturation from pumped to observed hyperfine transitions. SR ELDOR was found to be an essential method for measurements of saturation transfer rates for small molecules such as TEMPONE. Free induction decay (FID) signals for small nitroxides at W-band are also reported. Results are compared with multifrequency measurements of T1e previously reported for these molecules in the range of 2 to 35 GHz (J.S. Hyde et al., J. Phys. Chem. B 108 (2004) 9524–9529). The values of T1e decrease at 94 GHz relative to values at 35 GHz. PMID:18547848

  8. Packaging of microwave integrated circuits operating beyond 100 GHz

    NASA Technical Reports Server (NTRS)

    Samoska, L.; Daniel, E.; Sokolov, V.; Sommerfeldt, S.; Bublitz, J.; Olson, K.; Gilbert, B.; Chow, D.

    2002-01-01

    Several methods of packaging high speed (75-330 GHz) InP HEMT MMIC devices are discussed. Coplanar wirebonding is presented with measured insertion loss of less than 0.5dB and return loss better than -17 dB from DC to 110 GHz. A motherboard/daughterboard packaging scheme is presented which supports minimum loss chains of MMICs using this coplanar wirebonding method. Split waveguide block packaging approaches are presented in G-band (140-220 GHz) with two types of MMIC-waveguide transitions: E-plane probe andantipodal finline.

  9. Extending the ICRF to Higher Radio Frequencies: 24 and 43 GHz Astrometry

    NASA Technical Reports Server (NTRS)

    Jacobs, Christopher S.; Charlot, Patrick; Fomalont, Ed B.; Gordon, David; Lanyi, Gabor E.; Ma, Chopo; Naudet, Charles J.; Sovers, Ojars J.; Zhang, Li-Wei D.

    2004-01-01

    We present imaging results and source structure analysis of extragalactic radio sources observed using the Very Long Baseline Array (VLBA) at 24 GHz and 43 GHz as part of an ongoing NASA, USNO, NRAO and Bordeaux Observatory collaboration to extend the International Celestial Reference Frame (ICRF) to higher radio frequencies. The K/Q-band image database now includes images of 108 sources at 43 GHz (Q-band) and images of 230 sources at 24 GHz (K-band). Preliminary analysis of the observations taken to date shows that the sources are generally more compact as one goes from the ICRF frequency of 8.4 GHz to 24 GHz. This result is consistent with the standard theory of compact extragalactic radio sources and suggests that reference frames defined at these higher radio frequencies will be less susceptible to the effects of intrinsic source structure than those defined at lower frequencies.

  10. X-band uplink ground systems development: Part 2

    NASA Technical Reports Server (NTRS)

    Johns, C. E.

    1987-01-01

    The prototype X-band exciter testing has been completed. Stability and single-sideband phase noise measurements have been made on the X-band exciter signal (7.145-7.235 GHz) and on the coherent X- and S-band receiver test signals (8.4-8.5 GHz and 2.29-2.3 GHz) generated within the exciter equipment. Outputs are well within error budgets.

  11. The 60 GHz IMPATT diode development

    NASA Technical Reports Server (NTRS)

    Dat, Rovindra; Ayyagari, Murthy; Hoag, David; Sloat, David; Anand, Yogi; Whitely, Stan

    1986-01-01

    The objective is to develop 60 GHz IMPATT diodes suitable for communications applications. The performance goals of the 60 GHz IMPATT is 1W CW output power with a conversion efficiency of 15 percent and 10-year lifetime. The final design of the 60 GHz IMPATT structure evolved from computer simulations performed at the University of Michigan. The initial doping profile, involving a hybrid double-drift (HDD) design, was derived from a drift-diffusion model that used the static velocity-field characteristics for GaAs. Unfortunately, the model did not consider the effects of velocity undershoot and delay of the avalanche process due to energy relaxation. Consequently, the initial devices were oscillating at a much lower frequency than anticipated. With a revised simulation program that included the two effects given above, a second HDD profile was generated and was used as a basis for fabrication efforts. In the area of device fabrication, significant progress was made in epitaxial growth and characterization, wafer processing, and die assembly. The organo-metallic chemical vapor deposition (OMCVD) was used. Starting with a baseline X-Band IMPATT technology, appropriate processing steps were modified to satisfy the device requirements at V-Band. In terms of efficiency and reliability, the device requirements dictate a reduction in its series resistance and thermal resistance values. Qualitatively, researchers were able to reduce the diodes' series resistance by reducing the thickness of the N+ GaAs substrate used in its fabrication.

  12. The DSS-14 C-band exciter

    NASA Technical Reports Server (NTRS)

    Rowan, D. R.

    1989-01-01

    The development and implementation of a C-band exciter for use with the Block IV Receiver-Exciter Subsystem at Deep Space Station 14 (DSS-14) has been completed. The exciter supplements the standard capabilities of the Block IV system by providing a drive signal for the C-band transmitter while generating coherent translation frequencies for C-band (5-GHz) to S-band (2.2- to 2.3-GHz) Doppler extraction, C-band to L-band (1.6-GHz) zero delay measurements, and a level calibrated L-band test signal. Exciter functions are described, and a general explanation and description of the C-band uplink controller is presented.

  13. The DSS-14 C-band exciter

    NASA Astrophysics Data System (ADS)

    Rowan, D. R.

    1989-05-01

    The development and implementation of a C-band exciter for use with the Block IV Receiver-Exciter Subsystem at Deep Space Station 14 (DSS-14) has been completed. The exciter supplements the standard capabilities of the Block IV system by providing a drive signal for the C-band transmitter while generating coherent translation frequencies for C-band (5-GHz) to S-band (2.2- to 2.3-GHz) Doppler extraction, C-band to L-band (1.6-GHz) zero delay measurements, and a level calibrated L-band test signal. Exciter functions are described, and a general explanation and description of the C-band uplink controller is presented.

  14. A 3 to 5 GHz low-phase-noise fractional-N frequency synthesizer with adaptive frequency calibration for GSM/PCS/DCS/WCDMA transceivers

    NASA Astrophysics Data System (ADS)

    Yaohua, Pan; Niansong, Mei; Hu, Chen; Yumei, Huang; Zhiliang, Hong

    2012-01-01

    A low-phase-noise Σ—Δ fractional-N frequency synthesizer for GSM/PCS/DCS/WCDMA transceivers is presented. The voltage controlled oscillator is designed with a modified digital controlled capacitor array to extend the tuning range and minimize phase noise. A high-resolution adaptive frequency calibration technique is introduced to automatically choose frequency bands and increase phase-noise immunity. A prototype is implemented in 0.13 μm CMOS technology. The experimental results show that the designed 1.2 V wideband frequency synthesizer is locked from 3.05 to 5.17 GHz within 30 μs, which covers all five required frequency bands. The measured in-band phase noise are -89, -95.5 and -101 dBc/Hz for 3.8 GHz, 2 GHz and 948 MHz carriers, respectively, and accordingly the out-of-band phase noise are -121, -123 and -132 dBc/Hz at 1 MHz offset, which meet the phase-noise-mask requirements of the above-mentioned standards.

  15. A 32 GHz microstrip array antenna for microspacecraft application

    NASA Technical Reports Server (NTRS)

    Huang, J.

    1994-01-01

    JPL/NASA is currently developing microspacecraft systems for future deep space applications. One of the frequency bands being investigated for microspacecraft is the Ka-band (32 GHz), which can be used with smaller equipment and provides a larger bandwidth. This article describes the successful development of a circularly polarized microstrip array with 28 dBic of gain at 32 GHz. This antenna, which is thin, flat, and small, can be surface-mounted onto the microspacecraft and, hence, takes very little volume and mass of the spacecraft. The challenges in developing this antenna are minimizing the microstrip antenna's insertion loss and maintaining a reasonable frequency bandwidth.

  16. The 20/30 GHz satellite systems technology needs assessment

    NASA Technical Reports Server (NTRS)

    Stevens, G.; Wright, D.

    1978-01-01

    Rain attenuation in the 20/30 GHz bands, and the resultant impact on system user costs were estimated for a variety of satellite communication system concepts. Results of previous and current NASA Lewis contractual and in-house studies on system design are reported as well as market studies conducted to evaluate the concepts and test their relevancy against forecasted market needs. The 20/30 GHz bands appear attractive economically and, with certain technology, appear to offer a virtually unlimited spectrum resource. This attractiveness is especially relevant to high density trunking where there is sufficient traffic to justify dual-station site diversity.

  17. DNA strand breaks are not induced in human cells exposed to 2.1425 GHz band CW and W-CDMA modulated radiofrequency fields allocated to mobile radio base stations.

    PubMed

    Sakuma, N; Komatsubara, Y; Takeda, H; Hirose, H; Sekijima, M; Nojima, T; Miyakoshi, J

    2006-01-01

    We conducted a large-scale in vitro study focused on the effects of low level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system in order to test the hypothesis that modulated RF fields may act as a DNA damaging agent. First, we evaluated the responses of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole body SAR for general public exposure defined as a basic restriction in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and Wideband Code Division Multiple Access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced different levels of DNA damage. Human glioblastoma A172 cells and normal human IMR-90 fibroblasts from fetal lungs were exposed to mobile communication frequency radiation to investigate whether such exposure produced DNA strand breaks in cell culture. A172 cells were exposed to W-CDMA radiation at SARs of 80, 250, and 800 mW/kg and CW radiation at 80 mW/kg for 2 and 24 h, while IMR-90 cells were exposed to both W-CDMA and CW radiations at a SAR of 80 mW/kg for the same time periods. Under the same RF field exposure conditions, no significant differences in the DNA strand breaks were observed between the test groups exposed to W-CDMA or CW radiation and the sham exposed negative controls, as evaluated immediately after the exposure periods by alkaline comet assays. Our results confirm that low level exposures do not act as a genotoxicant up to a SAR of 800 mW/kg. PMID:16283663

  18. Phosphorylation and gene expression of p53 are not affected in human cells exposed to 2.1425 GHz band CW or W-CDMA modulated radiation allocated to mobile radio base stations.

    PubMed

    Hirose, H; Sakuma, N; Kaji, N; Suhara, T; Sekijima, M; Nojima, T; Miyakoshi, J

    2006-09-01

    A large-scale in vitro study focusing on low-level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system was conducted to test the hypothesis that modulated RF fields induce apoptosis or other cellular stress response that activate p53 or the p53-signaling pathway. First, we evaluated the response of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole-body SAR for general public exposure defined as a basic restriction by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and wideband code division multiple access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced apoptosis or any signs of stress. Human glioblastoma A172 cells were exposed to W-CDMA radiation at SARs of 80, 250, and 800 mW/kg, and CW radiation at 80 mW/kg for 24 or 48 h. Human IMR-90 fibroblasts from fetal lungs were exposed to both W-CDMA and CW radiation at a SAR of 80 mW/kg for 28 h. Under the RF field exposure conditions described above, no significant differences in the percentage of apoptotic cells were observed between the test groups exposed to RF signals and the sham-exposed negative controls, as evaluated by the Annexin V affinity assay. No significant differences in expression levels of phosphorylated p53 at serine 15 or total p53 were observed between the test groups and the negative controls by the bead-based multiplex assay. Moreover, microarray hybridization and real-time RT-PCR analysis showed no noticeable differences in gene expression of the subsequent downstream targets of p53 signaling involved in apoptosis between the test groups and the negative controls. Our results confirm that exposure to low-level RF signals up to 800 mW/kg does not induce p53-dependent apoptosis, DNA damage, or other stress response in human

  19. Tunable All-Solid-State Local Oscillators to 1900 GHz

    NASA Technical Reports Server (NTRS)

    Ward, John; Chattopadhyay, Goutam; Maestrini, Alain; Schlecht, Erich; Gill, John; Javadi, Hamid; Pukala, David; Maiwald, Frank; Mehdi, Imran

    2004-01-01

    We present a status report of an ongoing effort to develop robust tunable all-solid-state sources up to 1900 GHz for the Heterodyne Instrument for the Far Infrared (HIFI) on the Herschel Space Observatory. GaAs based multi-chip power amplifier modules at W-band are used to drive cascaded chains of multipliers. We have demonstrated performance from chains comprised of four doublers up to 1600 GHz as well as from a x2x3x3 chain to 1900 GHz. Measured peak output power of 23 (micro)W at 1782 GHz and 2.6 (micro)W at 1900 GHz has been achieved when the multipliers are cooled to 120K. The 1900 GHz tripler was pumped with a four anode tripler that produces a peak of 4 mW at 630 GHz when cooled to 120 K. We believe that these sources can now be used to pump hot electron bolometer (HEB) heterodyne mixers.ter (HEB) heterodyne mixers.

  20. 12 GHz Radio-Holographic Surface Measurements of the RRI 10.4~m Telescope

    NASA Astrophysics Data System (ADS)

    Balasubramanyam, R.; Venkatesh, S.; Raju, S. B.

    2009-09-01

    A modern Q-band low noise amplifier (LNA) front-end is being fitted to the 10.4~m millimeter-wave telescope at the Raman Research Institute (RRI) to support observations in the 40-50~GHz frequency range. To assess the suitability of the surface for this purpose, we measured the deviations of the primary surface from an ideal paraboloid using radio holography. We used the 11.6996 GHz beacon signal from the GSAT3 satellite, a 1.2~m reference antenna, commercial Ku-band Low Noise Block Convereters (LNBC) as the receiver front-ends and a Stanford Research Systems (SRS) lock-in amplifier as the backend. The LNBCs had independent free-running first local oscillators (LO). Yet, we recovered the correlation by using a radiatively injected common tone that served as the second local oscillator. With this setup, we mapped the surface deviations on a 64 × 64 grid and measured an rms surface deviation of ˜ 350~μm with a measurement accuracy of ˜ 50~μm.

  1. A DUAL-BAND MILLIMETER-WAVE KINETIC INDUCTANCE CAMERA FOR THE IRAM 30 m TELESCOPE

    SciTech Connect

    Monfardini, A.; Benoit, A.; Bideaud, A.; Swenson, L.; Cruciani, A.; Camus, P.; Hoffmann, C.; Desert, F. X.; Doyle, S.; Ade, P.; Mauskopf, P.; Tucker, C.; Roesch, M.; Leclercq, S.; Schuster, K. F.; Endo, A.; Baryshev, A.; Baselmans, J. J. A.; Ferrari, L.; Yates, S. J. C

    2011-06-01

    The Neel IRAM KIDs Array (NIKA) is a fully integrated measurement system based on kinetic inductance detectors (KIDs) currently being developed for millimeter wave astronomy. The instrument includes dual-band optics allowing simultaneous imaging at 150 GHz and 220 GHz. The imaging sensors consist of two spatially separated arrays of KIDs. The first array, mounted on the 150 GHz branch, is composed of 144 lumped-element KIDs. The second array (220 GHz) consists of 256 antenna-coupled KIDs. Each of the arrays is sensitive to a single polarization; the band splitting is achieved by using a grid polarizer. The optics and sensors are mounted in a custom dilution cryostat, with an operating temperature of {approx}70 mK. Electronic readout is realized using frequency multiplexing and a transmission line geometry consisting of a coaxial cable connected in series with the sensor array and a low-noise 4 K amplifier. The dual-band NIKA was successfully tested in 2010 October at the Institute for Millimetric Radio Astronomy (IRAM) 30 m telescope at Pico Veleta, Spain, performing in-line with laboratory predictions. An optical NEP was then calculated to be around 2 x 10{sup -16} W Hz{sup -1/2} (at 1 Hz) while under a background loading of approximately 4 pW pixel{sup -1}. This improvement in comparison with a preliminary run (2009) verifies that NIKA is approaching the target sensitivity for photon-noise limited ground-based detectors. Taking advantage of the larger arrays and increased sensitivity, a number of scientifically relevant faint and extended objects were then imaged including the Galactic Center SgrB2 (FIR1), the radio galaxy Cygnus A, and the NGC1068 Seyfert galaxy. These targets were all observed simultaneously in the 150 GHz and 220 GHz atmospheric windows.

  2. A Dual-band Millimeter-wave Kinetic Inductance Camera for the IRAM 30 m Telescope

    NASA Astrophysics Data System (ADS)

    Monfardini, A.; Benoit, A.; Bideaud, A.; Swenson, L.; Cruciani, A.; Camus, P.; Hoffmann, C.; Désert, F. X.; Doyle, S.; Ade, P.; Mauskopf, P.; Tucker, C.; Roesch, M.; Leclercq, S.; Schuster, K. F.; Endo, A.; Baryshev, A.; Baselmans, J. J. A.; Ferrari, L.; Yates, S. J. C.; Bourrion, O.; Macias-Perez, J.; Vescovi, C.; Calvo, M.; Giordano, C.

    2011-06-01

    The Néel IRAM KIDs Array (NIKA) is a fully integrated measurement system based on kinetic inductance detectors (KIDs) currently being developed for millimeter wave astronomy. The instrument includes dual-band optics allowing simultaneous imaging at 150 GHz and 220 GHz. The imaging sensors consist of two spatially separated arrays of KIDs. The first array, mounted on the 150 GHz branch, is composed of 144 lumped-element KIDs. The second array (220 GHz) consists of 256 antenna-coupled KIDs. Each of the arrays is sensitive to a single polarization; the band splitting is achieved by using a grid polarizer. The optics and sensors are mounted in a custom dilution cryostat, with an operating temperature of ~70 mK. Electronic readout is realized using frequency multiplexing and a transmission line geometry consisting of a coaxial cable connected in series with the sensor array and a low-noise 4 K amplifier. The dual-band NIKA was successfully tested in 2010 October at the Institute for Millimetric Radio Astronomy (IRAM) 30 m telescope at Pico Veleta, Spain, performing in-line with laboratory predictions. An optical NEP was then calculated to be around 2 × 10-16 W Hz-1/2 (at 1 Hz) while under a background loading of approximately 4 pW pixel-1. This improvement in comparison with a preliminary run (2009) verifies that NIKA is approaching the target sensitivity for photon-noise limited ground-based detectors. Taking advantage of the larger arrays and increased sensitivity, a number of scientifically relevant faint and extended objects were then imaged including the Galactic Center SgrB2 (FIR1), the radio galaxy Cygnus A, and the NGC1068 Seyfert galaxy. These targets were all observed simultaneously in the 150 GHz and 220 GHz atmospheric windows.

  3. A wideband 12 GHz down converter

    NASA Technical Reports Server (NTRS)

    Newman, B. A.; Rosenbaum, F. J.

    1972-01-01

    The design, fabrication, and evaluation of a single ended 12 GHz down-converter suitable for use in a low cost satellite ground terminal is described. The mixer uses waveguide, coaxial and MIC (microwave integrated circuit) transmission line components. Theoretical and experimental analyses of several microstrip circuit elements are presented including the traveling wave-directional filter, quarter wave-length proximity directional coupler, low pass filter and the quarterwave band stop filter. The optimum performance achieved for the mixer using a packaged diode was 9.4 db conversion loss and a bandwidth of 275 MHz.

  4. Megawatt-power Ka-band gyroklystron oscillator with external feedback

    NASA Astrophysics Data System (ADS)

    Guznov, Y. M.; Danilov, Y. Y.; Kuzikov, S. V.; Novozhilova, Y. V.; Shevchenko, A. S.; Zaitsev, N. I.; Ryskin, N. M.

    2013-10-01

    We report design and experimental demonstration of a high-power regenerative oscillator based on the gyroklystron amplifier with external delayed feedback. The oscillator operates on axially non-symmetric TE7.1.1 and TE7.3.1 modes in the input and output cavity, respectively. Peak output power of 1.5-2.0 MW with nearly 1 μs pulse duration in Ka-band is observed experimentally. Application of the selective delayed feedback not only overcomes the mode competition problem but also provides controlled mode switching within 1-2 GHz frequency band.

  5. Towards an All-Sky 32 GHz Celestial Reference Frame

    NASA Astrophysics Data System (ADS)

    Horiuchi, S.; Phillips, C.; Jacobs, Christopher S.; Sotuela, I.; García-Miró, C.

    2012-07-01

    We have been developing a celestial reference frame catalogue at 32 GHz using 34m Beam Wave Guide antennas of NASA Deep Space Network to complement the current IAU standard S/X-band ICRF2. However, the DSN VLBI network alone can only cover limited part of the full sky, missing in the declination range from -45 to -90 degree. To extend the 32 GHz catalogue, we recently initiated a project to survey candidate catalogue sources in the southern sky using Canberra DSS-34 antenna in conjunction with two elements of LBA that can observe at 32 GHz, the Mopra telescope and ATCA. We formed a list of 144 new 32 GHz candidate catalogue sources at -90 < Dec. < -45 deg. as target sources of this pilot survey. We selected those sources as expected to be reasonably strong and compact for our purpose, considering estimated flux densities at 32 GHz based on the results of the ATCA 20 GHz (AT20G) survey with 8.6 GHz flux density measurements, as well as characteristics of the X-band unresolved components based on the RFC2011c version catalogue sources. The candidate list of 144 sources includes 46 ICRF2 sources with 29 "Defining" objects. This would allow cross-checking with the S/X results of ICRF2. The ultimate goal of our project is to establish a reference source catalogue at 32 GHz for the south polar cap region, which has never been covered in existing catalogues at that frequency. The catalogue can be used for future space navigation as well as astronomical and geodetic observations with southern radio telescope arrays such as ATCA and LBA.

  6. The 20 GHz spacecraft FET solid state transmitter

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The engineering development of a solid state transmitter amplifier operating in the 20 GHz frequency band using GaAs field effect transistors (FETs) was detailed. The major efforts include GaAs FET device development, single-ended amplifier stage, balanced amplifier stage, cascaded stage and radial combiner designs, and amplifier integration and test. A multistage GaAs FET amplifier capable of 8.2 W CW output over the 17.9 to 19.1 GHz frequency band was developed. The GaAs FET devices developed represent state of the art FET power device technology. Further device improvements are necessary to increase the bandwidth to 2.5 GHz, improve dc-to-RF efficiency, and increase power capability at the device level. Higher power devices will simplify the amplifier combining scheme, reducing the size and weight of the overall amplifier.

  7. An SIS Waveguide heterodyne Reciever for 600 GHz - 635 GHz

    NASA Technical Reports Server (NTRS)

    Salez, Morvan; Febvre, Pascal; McGrath, William R.; Bumble, Bruce; LeDuc, Henry G.

    1994-01-01

    A waveguide SIS heterodyne receiver using a Nb/A10xNb junction has been built for astronomical observations of molecular tranitions in the frequency range 600GHz - 635GHZ, and has been successfully used at the Caltech Submillimeter Observatory (CSO).

  8. 180-GHz Interferometric Imager

    NASA Technical Reports Server (NTRS)

    Kangaslahti, Pekka P.; Lim, Boon H.; O'Dwyer, Ian J.; Soria, Mary M.; Owen, Heather R.; Gaier, Todd C.; Lambrigtsen, Bjorn, H.; Tanner, Alan B.; Ruf, Christopher

    2011-01-01

    A 180-GHz interferometric imager uses compact receiver modules, combined high- and low-gain antennas, and ASIC (application specific integrated circuit) correlator technology, enabling continuous, all-weather observations of water vapor with 25-km resolution and 0.3-K noise in 15 minutes of observation for numerical weather forecasting and tropical storm prediction. The GeoSTAR-II prototype instrument is broken down into four major subsystems: the compact, low-noise receivers; sub-array modules; IF signal distribution; and the digitizer/correlator. Instead of the single row of antennas adopted in GeoSTAR, this version has four rows of antennas on a coarser grid. This dramatically improves the sensitivity in the desired field of view. The GeoSTAR-II instrument is a 48-element, synthetic, thinned aperture radiometer operating at 165-183 GHz. The instrument has compact receivers integrated into tiles of 16 elements in a 4x4 arrangement. These tiles become the building block of larger arrays. The tiles contain signal distribution for bias controls, IF signal, and local oscillator signals. The IF signals are digitized and correlated using an ASIC correlator to minimize power consumption. Previous synthetic aperture imagers have used comparatively large multichip modules, whereas this approach uses chip-scale modules mounted on circuit boards, which are in turn mounted on the distribution manifolds. This minimizes the number of connectors and reduces system mass. The use of ASIC technology in the digitizers and correlators leads to a power reduction close to an order of magnitude.

  9. The 20 GHz power GaAs FET development

    NASA Technical Reports Server (NTRS)

    Crandell, M.

    1986-01-01

    The development of power Field Effect Transistors (FET) operating in the 20 GHz frequency band is described. The major efforts include GaAs FET device development (both 1 W and 2 W devices), and the development of an amplifier module using these devices.

  10. Characteristics of ocular temperature elevations after exposure to quasi- and millimeter waves (18-40 GHz)

    NASA Astrophysics Data System (ADS)

    Kojima, Masami; Suzuki, Yukihisa; Tsai, Cheng-Yu; Sasaki, Kensuke; Wake, Kanako; Watanabe, Soichi; Taki, Masao; Kamimura, Yoshitsugu; Hirata, Akimasa; Sasaki, Kazuyuki; Sasaki, Hiroshi

    2015-04-01

    In order to investigate changes in ocular temperature in rabbit eyes exposed to different frequencies (18 to 40 GHz) of quasi-millimeter waves, and millimeter waves (MMW). Pigmented rabbits were anesthetized with both general and topical anesthesia, and thermometer probes (0.5 mm in diameter) were inserted into their cornea (stroma), lens (nucleus) and vitreous (center of vitreous). The eyes were exposed unilaterally to 200 mW/cm2 by horn antenna for 3 min at 18, 22 and 26.5 GHz using a K band exposure system or 26.5, 35 and 40 GHz using a Ka band exposure system. Changes in temperature of the cornea, lens and vitreous were measured with a fluoroptic thermometer. Since the ocular temperatures after exposure to 26.5 GHz generated by the K band and Ka band systems were similar, we assumed that experimental data from these 2 exposure systems were comparable. The highest ocular temperature was induced by 40 GHz MMW, followed by 35 GHz. The 26.5 and 22 GHz corneal temperatures were almost the same. The lowest temperature was recorded at 18 GHz. The elevation in ocular temperature in response to exposure to 200 mW/cm2 MMW is dependent on MMW frequency. MMW exposure induced heat is conveyed not only to the cornea but also the crystalline lens.

  11. A Novel UWB Antenna with Dual Band-Notched Characteristics

    NASA Astrophysics Data System (ADS)

    Lin, Yongfan; Liang, Jiangang; Wu, Goucheng; Xu, Zhiyong; Niu, Xuebin

    2015-11-01

    In this article, started from analyzing the basic principle of band-notched characteristics, a feasibly method used for band-notched antenna is demonstrated and the equivalent circuit for this method is designed. A novel UWB antenna is designed. Based on this method, two stubs which can be equivalent to shorted stubs in parallel configuration are added to realize dual band-notched characteristics. Simulated and measured results all show that the UWB antenna yields an impendence bandwidth of 2.0-10.6 GHz by defining VSWR ≦ 2, and two obvious band-notched functions (3.27-3.83 GHz, 4.60-5.90 GHz) occur at the working bandwidth of WIMAX (3.3-3.7 GHz) and HiperLAN/2 (5.15-5.35 GHz, 5.47-5.725 GHz), so the electromagnetic interference between UWB application and WIMAX, HiperLAN/2 can be suppressed.

  12. Saturation recovery EPR and ELDOR at W-band for spin labels.

    PubMed

    Froncisz, Wojciech; Camenisch, Theodore G; Ratke, Joseph J; Anderson, James R; Subczynski, Witold K; Strangeway, Robert A; Sidabras, Jason W; Hyde, James S

    2008-08-01

    A reference arm W-band (94 GHz) microwave bridge with two sample-irradiation arms for saturation recovery (SR) EPR and ELDOR experiments is described. Frequencies in each arm are derived from 2 GHz synthesizers that have a common time-base and are translated to 94 GHz in steps of 33 and 59 GHz. Intended applications are to nitroxide radical spin labels and spin probes in the liquid phase. An enabling technology is the use of a W-band loop-gap resonator (LGR) [J.W. Sidabras, R.R. Mett, W. Froncisz, T.G. Camenisch, J.R. Anderson, J.S. Hyde, Multipurpose EPR loop-gap resonator and cylindrical TE(011) cavity for aqueous samples at 94 GHz, Rev. Sci. Instrum. 78 (2007) 034701]. The high efficiency parameter (8.2 GW(-1/2) with sample) permits the saturating pump pulse level to be just 5 mW or less. Applications of SR EPR and ELDOR to the hydrophilic spin labels 3-carbamoyl-2,2,5,5-tetra-methyl-3-pyrroline-1-yloxyl (CTPO) and 2,2,6,6,-tetramethyl-4-piperidone-1-oxyl (TEMPONE) are described in detail. In the SR ELDOR experiment, nitrogen nuclear relaxation as well as Heisenberg exchange transfer saturation from pumped to observed hyperfine transitions. SR ELDOR was found to be an essential method for measurements of saturation transfer rates for small molecules such as TEMPONE. Free induction decay (FID) signals for small nitroxides at W-band are also reported. Results are compared with multifrequency measurements of T(1e) previously reported for these molecules in the range of 2-35 GHz [J.S. Hyde, J.-J. Yin, W.K. Subczynski, T.G. Camenisch, J.J. Ratke, W. Froncisz, Spin label EPR T(1) values using saturation recovery from 2 to 35 GHz. J. Phys. Chem. B 108 (2004) 9524-9529]. The values of T(1e) decrease at 94 GHz relative to values at 35 GHz. PMID:18547848

  13. A 250 GHz gyrotron with a 3 GHz tuning bandwidth for dynamic nuclear polarization.

    PubMed

    Barnes, Alexander B; Nanni, Emilio A; Herzfeld, Judith; Griffin, Robert G; Temkin, Richard J

    2012-08-01

    We describe the design and implementation of a novel tunable 250 GHz gyrotron oscillator with >10 W output power over most of a 3 GHz band and >35 W peak power. The tuning bandwidth and power are sufficient to generate a >1 MHz nutation frequency across the entire nitroxide EPR lineshape for cross effect DNP, as well as to excite solid effect transitions utilizing other radicals, without the need for sweeping the NMR magnetic field. Substantially improved tunability is achieved by implementing a long (23 mm) interaction cavity that can excite higher order axial modes by changing either the magnetic field of the gyrotron or the cathode potential. This interaction cavity excites the rotating TE(₅,₂,q) mode, and an internal mode converter outputs a high-quality microwave beam with >94% Gaussian content. The gyrotron was integrated into a DNP spectrometer, resulting in a measured DNP enhancement of 54 on the membrane protein bacteriorhodopsin. PMID:22743211

  14. A 250 GHz gyrotron with a 3 GHz tuning bandwidth for dynamic nuclear polarization

    NASA Astrophysics Data System (ADS)

    Barnes, Alexander B.; Nanni, Emilio A.; Herzfeld, Judith; Griffin, Robert G.; Temkin, Richard J.

    2012-08-01

    We describe the design and implementation of a novel tunable 250 GHz gyrotron oscillator with >10 W output power over most of a 3 GHz band and >35 W peak power. The tuning bandwidth and power are sufficient to generate a >1 MHz nutation frequency across the entire nitroxide EPR lineshape for cross effect DNP, as well as to excite solid effect transitions utilizing other radicals, without the need for sweeping the NMR magnetic field. Substantially improved tunability is achieved by implementing a long (23 mm) interaction cavity that can excite higher order axial modes by changing either the magnetic field of the gyrotron or the cathode potential. This interaction cavity excites the rotating TE5,2,q mode, and an internal mode converter outputs a high-quality microwave beam with >94% Gaussian content. The gyrotron was integrated into a DNP spectrometer, resulting in a measured DNP enhancement of 54 on the membrane protein bacteriorhodopsin.

  15. A 250 GHz Gyrotron with a 3 GHz Tuning Bandwidth for Dynamic Nuclear Polarization

    PubMed Central

    Barnes, Alexander B.; Nanni, Emilio A.; Herzfeld, Judith; Griffin, Robert G.; Temkin, Richard J.

    2012-01-01

    We describe the design and implementation of a novel tunable 250 GHz gyrotron oscillator with >10 W output power over most of a 3 GHz band and >35 W peak power. The tuning bandwidth and power are sufficient to generate a >1 MHz nutation frequency across the entire nitroxide EPR lineshape for cross effect DNP, as well as to excite solid effect transitions utilizing other radicals, without the need for sweeping the NMR magnetic field. Substantially improved tunability is achieved by implementing a long (23 mm) interaction cavity that can excite higher order axial modes by changing either the magnetic field of the gyrotron or the cathode potential. This interaction cavity excites the rotating TE5,2,q mode, and an internal mode converter outputs a high-quality microwave beam with >94% Gaussian content. The gyrotron was integrated into a DNP spectrometer, resulting in a measured DNP enhancement of 54 on the membrane protein bacteriorhodopsin. PMID:22743211

  16. A low noise CMOS RF front-end for UWB 6-9 GHz applications

    NASA Astrophysics Data System (ADS)

    Feng, Zhou; Ting, Gao; Fei, Lan; Wei, Li; Ning, Li; Junyan, Ren

    2010-11-01

    An integrated fully differential ultra-wideband CMOS RF front-end for 6-9 GHz is presented. A resistive feedback low noise amplifier and a gain controllable IQ merged folded quadrature mixer are integrated as the RF front-end. The ESD protected chip is fabricated in a TSMC 0.13 μm RF CMOS process and achieves a maximum voltage gain of 23-26 dB and a minimum voltage gain of 16-19 dB, an averaged total noise figure of 3.3-4.6 dB while operating in the high gain mode and an in-band IIP3 of -12.6 dBm while in the low gain mode. This RF front-end consumes 17 mA from a 1.2 V supply voltage.

  17. Dual-band operation of a microstrip patch antenna on a Duroid 5870 substrate for Ku- and K-bands.

    PubMed

    Islam, M M; Islam, M T; Faruque, M R I

    2013-01-01

    The dual-band operation of a microstrip patch antenna on a Duroid 5870 substrate for Ku- and K-bands is presented. The fabrication of the proposed antenna is performed with slots and a Duroid 5870 dielectric substrate and is excited by a 50 Ω microstrip transmission line. A high-frequency structural simulator (HFSS) is used which is based on the finite element method (FEM) in this research. The measured impedance bandwidth (2 : 1 VSWR) achieved is 1.07 GHz (15.93 GHz-14.86 GHz) on the lower band and 0.94 GHz (20.67-19.73 GHz) on the upper band. A stable omnidirectional radiation pattern is observed in the operating frequency band. The proposed prototype antenna behavior is discussed in terms of the comparisons of the measured and simulated results. PMID:24385878

  18. Magnetic dimers and trimers in the disordered S =3/2 spin system BaTi1/2Mn1/2O3

    NASA Astrophysics Data System (ADS)

    Garcia, F. A.; Kaneko, U. F.; Granado, E.; Sichelschmidt, J.; Hölzel, M.; Duque, J. G. S.; Nunes, C. A. J.; Amaral, R. P.; Marques-Ferreira, P.; Lora-Serrano, R.

    2015-06-01

    We report a structural-magnetic investigation by x-ray absorption spectroscopy (XAS), neutron diffraction, dc susceptibility (χdc), and electron spin resonance (ESR) of the 12R-type perovskite BaTi1/2Mn1/2O3 . Our structural analysis by neutron diffraction supports the existence of structural trimers with chemically disordered occupancy of Mn4+ and Ti4+ ions, with the valence of the Mn ions confirmed by the XAS measurements. The magnetic properties are explored by combining dc-susceptibility and X -band (9.4 GHz) electron spin resonance, both in the temperature interval of 2 ≤T ≤1000 K. A scenario is presented under which the magnetism is explained by considering magnetic dimers and trimers, with exchange constants Ja/kB=200 (2 ) K and Jb/kB=130 (10 ) K, and orphan spins. Thus, BaTi1/2Mn1/2O3 is proposed as a rare case of an intrinsically disordered S =3/2 spin gap system with a frustrated ground state.

  19. Research on CSS 1150+497 (4C49.22) in the radio band

    NASA Astrophysics Data System (ADS)

    Wang, Bao-Tian; Zhang, Hai-Yan

    2006-12-01

    The compact steep spectrum (CSS) source 1150+497 was observed with the Very Long Baseline Array (VLBA) at 5GHz and 8GHz bands. The obtained total intensity image at 5GHz shows that 1150+497 has a bright one-side jet. At 5GHz, there are 3 knots in the southwest and one knot in the northeast. At 8GHz, two knots can be modeled in the southwest. Analyzing images at 5GHz band in 3 epochs from 1982 to 2001, an estimate of separation velocity 0.478 ± 0.007 mas/year is derived as the relative motions in components A and E.

  20. Ku-band miniature modulators

    NASA Technical Reports Server (NTRS)

    Ernst, R. L.

    1973-01-01

    Ku-band microminiature modulators were designed to convert a 10 mW signal at 400 MHz to a 10 mW signal at 15 GHz. The designs incorporate gallium arsenide Schottky barrier varactors used in upper-sideband up-converters. The use of Ku-band microstrip circulators and hairpin resonator bandpass filters at 2.1 GHz and 2.5 GHz is included. The design and fabrication of a single up-conversion unit with a double up-conversion unit are compared. Various filter configurations are studies, and the use of both alumina and quartz substrates are considered. The various impedance matching networks are evaluated using computer aided design techniques.

  1. A compact triple-band bandpass filter based on metamaterials

    NASA Astrophysics Data System (ADS)

    Zhao, Ya-juan; Jiang, Bo; Li, Bao-yi; Wang, Dong-hong

    2016-07-01

    This paper presents a compact triple-band bandpass filter based on metamaterials. The miniaturization is realized by the principle of phase compensation of metamaterial. Compared with the conventional half-wavelength filter, the metamaterial filter has a small size of 10 mm×10 mm. The triple-band bandpass filter performance has been validated by the electromagnetic simulation software of high frequency structure simulator (HFSS). The results illustrate that the filter is designed with center frequencies of 2.4 GHz, 5.1 GHz and 8.8 GHz, bandwidths of about 7.9% (2.31—2.50 GHz), 7.8% (5.0—5.4 GHz) and 7.4% (8.50—9.15 GHz), respectively, and it shows good band pass characteristics.

  2. Effect of the [Ba2BO3F]∞ Layer on the Band Gap: Synthesis, Characterization, and Theoretical Studies of BaZn2B2O6·nBa2BO3F (n = 0, 1, 2).

    PubMed

    Wu, Hongping; Su, Xin; Han, Shujuan; Yang, Zhihua; Pan, Shilie

    2016-05-16

    Two new zincoborate fluorides with the common formula BaZn2B2O6·nBa2BO3F (n = 1, 2) have been successfully synthesized for the relationship study between the band gaps and crystal structures in zinc-containing borate fluorides. Ba3Zn2B3O9F with n = 1 in the common formula belongs to the orthorhombic space group Pnma (No. 20), and Ba5Zn2B4O12F2 with n = 2 in the common formula crystallizes in the monoclinic space group C2/c (No. 62). They can both be seen as compounds with the n[Ba2BO3F]∞ (n = 1 or 2) layer inserted in the structure of BaZn2B2O6. UV-vis-near-IR diffuse-reflectance spectra show that the band gaps of BaZn2B2O6·nBa2BO3F (n = 0, 1, 2) gradually increase with more [Ba2BO3F]∞ layers inserted. The first-principles calculation indicates that the inserted n[Ba2BO3F]∞ layers play a positive effect in increasing the band gaps of zincoborate fluorides. Furthermore, the IR spectra, thermal behaviors, and refractive indices of these compounds are also studied. PMID:27119618

  3. ISM band to U-NII band frequency transverter and method of frequency transversion

    DOEpatents

    Stepp, Jeffrey David; Hensley, Dale

    2006-04-04

    A frequency transverter (10) and method for enabling bi-frequency dual-directional transfer of digitally encoded data on an RF carrier by translating between a crowded or otherwise undesirable first frequency band, such as the 2.4 GHz ISM band, and a less-crowded or otherwise desirable second frequency band, such as the 5.0 GHz-6.0 GHz U-NII band. In a preferred embodiment, the transverter (10) connects between an existing data radio (11) and its existing antenna (30), and comprises a bandswitch (12); an input RF isolating device (14); a transmuter (16); a converter (18); a dual output local oscillator (20); an output RF isolating device (22); and an antenna (24) tuned to the second frequency band. The bandswitch (12) allows for bypassing the transverter (10), thereby facilitating its use with legacy systems. The transmuter (14) and converter (16) are adapted to convert to and from, respectively, the second frequency band.

  4. ISM band to U-NII band frequency transverter and method of frequency transversion

    DOEpatents

    Stepp, Jeffrey David; Hensley, Dale

    2006-09-12

    A frequency transverter (10) and method for enabling bi-frequency dual-directional transfer of digitally encoded data on an RF carrier by translating between a crowded or otherwise undesirable first frequency band, such as the 2.4 GHz ISM band, and a less-crowded or otherwise desirable second frequency band, such as the 5.0 GHz 6.0 GHz U-NII band. In a preferred embodiment, the transverter (10) connects between an existing data radio (11) and its existing antenna (30), and comprises a bandswitch (12); an input RF isolating device (14); a transmuter (16); a converter (18); a dual output local oscillator (20); an output RF isolating device (22); and an antenna (24) tuned to the second frequency band. The bandswitch (12) allows for bypassing the transverter (10), thereby facilitating its use with legacy systems. The transmuter (14) and converter (16) are adapted to convert to and from, respectively, the second frequency band.

  5. Electromagnetic interference shielding in 1-18 GHz frequency and electrical property correlations in poly(vinylidene fluoride)-multi-walled carbon nanotube composites.

    PubMed

    Kumar, G Sudheer; Vishnupriya, D; Joshi, Anupama; Datar, Suwarna; Patro, T Umasankar

    2015-08-21

    Electromagnetic interference (EMI) shielding properties in the 1-18 GHz frequency range for multi-walled carbon nanotube (MWNT)-poly(vinylidene fluoride) (PVDF) composites are reported. A simple and gentle acid-treatment of MWNT showed a percolation threshold (PT) of 0.15 wt% in the PVDF matrix as against 0.35 wt% for unfunctionalized MWNT. Acid-treatment of MWNT significantly improves dispersion, interfacial adhesion with the matrix and the EMI shielding properties of PVDF composites. Further, the EMI shielding properties are correlated with the electrical properties. Using composite films of 0.3 mm thickness, the maximum shielding effectiveness (SET) values for 4 wt% unfunctionalized MWNT composites are found to be about 110, 45, 30, 26, and 58 dB for L (1-2 GHz), S (2-4 GHz), C (4-5.8 GHz), J (5.8-8 GHz), and X (8-12 GHz) bands, while the corresponding values for only 0.5 wt% acid functionalized MWNT composites are about 98, 45, 26, 19, and 47 dB, respectively. The electrical conductivity for both the cases is ∼10(-3) S cm(-1) and the weight contents of CNTs are higher than the PT for the respective composites. The comparable EMI SE and electrical conductivity values for both the composites at different weight fractions of CNTs suggest that there is a critical electrical conductivity above which the composites attain improved EMI shielding properties. Further, the shielding mechanism was found to be dominated by absorption loss. Therefore, the composites may also serve as a radar absorbing material. PMID:26194165

  6. Analysis of the (1)A' S1 ← (1)A' S0 and (2)A' D0 ← (1)A' S1 band systems in 1,2-dichloro-4-fluorobenzene by means of resonance-enhanced-multi-photon-ionization (REMPI) and mass-analyzed-threshold-ionization (MATI) spectroscopy.

    PubMed

    Krüger, Sascha; Grotemeyer, Jürgen

    2016-03-14

    Resonance enhanced multiphoton ionization (REMPI) and mass analyzed threshold ionization (MATI) spectroscopy have been applied in order to investigate the vibrational structure of 1,2-dichloro-4-fluorobenzene (1,2,4-DCFB) in its first excited state (S1) and the cationic ground state (D0). The selection of the state prior to ionization resulted in MATI spectra with different intensity distributions thus giving access to many vibrational levels. To support the experimental findings, geometry optimizations and frequency analyses at DFT (density functional) and TDDFT (time-dependent density functional) levels of theory have been applied. Additionally, a multidimensional Franck-Condon approach has been used to calculate the vibrational intensities from the DFT calculations. An excellent agreement between simulated and measured REMPI and MATI spectra allowed for a confident assignment of vibrational levels and mechanisms active during excitation and ionization. In order to avoid any ambiguity regarding the assignment of the vibrational bands to normal modes, Duschinsky normal mode analysis has been performed to correlate the ground state (S0) normal modes of 1,2,4-DCFB with the benzene derived Wilson nomenclature. From the REMPI spectra the electronic excitation energy (EE) of 1,2-dichloro-4-fluorobenzene could be determined to be 35 714 ± 2 cm(-1) while the MATI spectra yielded the adiabatic ionization energy (IE) of 1,2-dichloro-4-fluorobenzene which could be determined to be 73 332 ± 7 cm(-1). PMID:26884269

  7. Microwave electromagnetic and absorption properties of Nd2Fe14B/α-Fe nanocomposites in the 0.5-18 and 26.5-40 GHz ranges

    NASA Astrophysics Data System (ADS)

    Lian, Li-Xian; Deng, L. J.; Han, M.; Tang, W.; Feng, Shao-Dong

    2007-05-01

    Nd2Fe14B/α-Fe nanocomposites were prepared using a melt-spinning method, subsequent annealing treatment, and ball milling. The complex permittivity and permeability of the composites were measured in the 0.5-18 and 26.5-40GHz frequency ranges. The permeability spectra of the Nd2Fe14B/α-Fe nanocomposites exhibit relaxation and resonance type characteristic in the 0.5-18 and 26.5-40GHz frequency ranges, respectively. The resonance frequency (fr) of Nd10Fe78Co5Zr1B6 nanocomposite is 30GHz due to the large anisotropy field (HA). However, the resonance frequency of the Nd2Fe14B/α-Fe sample is lower than that of Nd2Fe14B, due to the decrease of HA induced by the exchange interaction between hard and soft magnetic phases. These samples also showed good microwave absorption performance (reflection loss: <-20dB) in 9, 17, and 35-38GHz with matching thicknesses of 2, 1.2, and 0.37mm, respectively. Therefore, Nd2Fe14B/α-Fe nanocomposites are thought to be a potential candidate for thinner microwave absorbers not only in the centimeter wave but also in the millimeter wave band.

  8. Analysis of single pulse radio flux measurements of PSR B1133+16 at 4.85 and 8.35 GHz

    NASA Astrophysics Data System (ADS)

    Krzeszowski, K.; Maron, O.; Słowikowska, A.; Dyks, J.; Jessner, A.

    2014-05-01

    We show the results of microsecond resolution radio data analysis focused on flux measurements of single pulses of PSR B1133+16. The data were recorded at 4.85 and 8.35 GHz with 0.5- and 1.1-GHz bandwidth, respectively, using Radio Telescope Effelsberg (Max-Planck-Institut für Radioastronomie). The most important conclusion of the analysis is that the strongest single pulse emission at 4.85 and 8.35 GHz contributes almost exclusively to the trailing part of the leading component of the pulsar mean profile, whereas studies at lower frequencies report that the contribution is spread almost uniformly, covering all phases of the pulsar mean profile. We also estimate the radio emission heights to be around 1-2 per cent of the light-cylinder radius, which is in agreement with previous studies. Additionally, these observations allowed us to add two more measurements of the flux density to the PSR B1133+16 broad-band radio spectrum, covering frequencies from 16.7 MHz up to 32 GHz. We fit two different models to the spectrum: a broken power law and a spectrum based on the flicker-noise model, which represents the spectrum in a simpler, but similarly accurate, way.

  9. Towards monitoring of geohazards with ESA's Sentinel-1 C-band SAR data: nationwide feasibility mapping over Great Britain calibrated using ERS-1/2 and ENVISAT PSI data

    NASA Astrophysics Data System (ADS)

    Cigna, Francesca; Bateson, Luke; Dashwood, Claire; Jordan, Colm

    2013-04-01

    Following the success of its predecessors ERS-1/2 and ENVISAT, ESA's Sentinel-1 constellation will provide routine, free of charge and globally-available Synthetic Aperture Radar (SAR) observations of the Earth's surface starting in 2013, with 12day repeat cycle and up to 5m spatial resolution. The upcoming availability of this unprecedented and long-term radar-based observation capacity is stimulating new scientific and operational perspectives within the geohazards and land monitoring community, who initiated and is being working on target preparatory studies to exploit this attractive and rich reservoir of SAR data for, among others, interferometric applications. The Earth and Planetary Observation and Monitoring, and the Shallow Geohazards and Risks Teams of the British Geological Survey (BGS) are routinely assessing new technologies for geohazard mapping, and carrying out innovative research to improve the understanding of landslide processes and their dynamics. Building upon the successful achievements of recent applications of Persistent Scatterer Interferometry (PSI) to geohazards mapping and monitoring in Europe, and with the aim of enhancing further the research on radar EO for landslide management in Britain, since the beginning of 2012 the BGS has been carrying out a research project funded by internal NERC grants aimed at evaluating the potential of these techniques to better understand landslide processes over Great Britain. We mapped the PSI feasibility over the entire landmass, based on the combination of topographic and landuse effects which were modelled by using medium to high resolution DEMs, land cover information from the EEA CORINE Land Cover map 2006, and six PSI datasets over London, Stoke-on-Trent, Bristol/Bath, and the Northumberland-Durham region, made available to BGS through the projects ESA-GMES Terrafirma and EC-FP7 PanGeo. The feasibility maps for the ERS-1/2 and ENVISAT ascending and descending modes showed that topography is not

  10. A 83 GHz InP DHBT static frequency divider

    NASA Astrophysics Data System (ADS)

    Youtao, Zhang; Xiaopeng, Li; Min, Zhang; Wei, Cheng; Xinyu, Chen

    2014-04-01

    A static frequency divider is presented using 0.7 μm InP DHBTs with 280 GHz ft/fmax. The divider is based on ECL master-slave D-flip-flop topology with 30 HBTs and 20 resistors with a chip size 0.62 × 0.65 mm2. The circuits use peaking inductance as a part of the loads to maximize the highest clock rate. Momentum simulation is used to accurately characterize the effect of the clock feedback lines at the W band. Test results show that the divider can operate from 1 GHz up to 83 GHz. Its phase noise is 139 dBc/Hz with 100 kHz offset. The power dissipation of divider core is 350 mW.

  11. 32 GHz Celestial Reference Frame Survey for Dec. < -45 °

    NASA Astrophysics Data System (ADS)

    Horiuchi, S.; Jacobs, C. S.; Phillips, C.; Sotuela, I.; García-Miró, C.

    2012-12-01

    We have been developing a celestial reference frame at 32 GHz using the 34-m Beam Wave Guide antennas of NASA's Deep Space Network (DSN) to complement the current IAU standard ICRF2 at S/X-band. However, the DSN VLBI network alone can only cover a limited part of the full sky, missing the declination range from -45 to -90 degrees. To extend the 32 GHz frame, we recently initiated a project to survey candidate sources in the southern sky using Canberra's DSS-34 antenna in conjunction with two elements of the Australian Long Baseline Array (LBA) that can observe at 32 GHz: the Mopra Radio Relescope and the Australian Telescope Compact Array (ATCA).

  12. 32 GHz Celestial Reference Frame Survey for Dec < -45 deg

    NASA Astrophysics Data System (ADS)

    Horiuchi, S.; Phillips, C.; Sotuela, I.; Jacobs, Christopher S.; García-Miró, C.

    2012-03-01

    We have been developing a celestial reference frame at 32 GHz using the 34-m Beam Wave Guide antennas of NASA's Deep Space Network (DSN) to complement the current IAU standard ICRF2 at S/X-band. However, the DSN VLBI network alone can only cover a limited part of the full sky, missing the declination range from -45 to -90 degrees. To extend the 32 GHz frame, we recently initiated a project to survey candidate sources in the southern sky using Canberra's DSS-34 antenna in conjunction with two elements of the Australian Long Baseline Array (LBA) that can observe at 32 GHz: the Mopra Radio Relescope and the Australian Telescope Compact Array (ATCA).

  13. Molecular structure and vibrational bands and chemical shift assignments of 4-allyl-5-(2-hydroxyphenyl)-2,4-dihydro-3H-1,2,4-triazole-3-thione by DFT and ab initio HF calculations

    NASA Astrophysics Data System (ADS)

    Karakurt, Tuncay; Dinçer, Muharrem; Çetin, Ahmet; Şekerci, Memet

    2010-09-01

    The title molecule, 4-allyl-5-(2-hydroxyphenyl)-2,4-dihydro-3H-1,2,4-triazole-3-thione (C 11H 11N 3OS), was synthesized and characterized by IR-NMR spectroscopy and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group is P2 1/ c, a = 9.0907(5) Å, b = 9.1288(7) Å, c = 13.6222(7) Å, α = 90°, β = 98.442 (4), γ = 90° and V = 2683.7(6) Å 3, F(000) = 488, Dx = 1.386 g/cm 3. In addition to the molecular geometry from X-ray experiment, the molecular geometry, vibrational frequencies, gauge including atomic orbital (GIAO) 1H and 13C chemical shift values of the title compound in the ground state have been calculated using the Hartree-Fock (HF) and density functional method (DFT/BLYP and DFT/B3LYP) with 6-31G(d) basis set. To determine conformational flexibility, molecular energy profile of the title compound was obtained by HF/6-31G(d) calculations with respect to selected degree of torsional freedom, which was varied from -180° to +180° in steps of 10°. Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO), and several thermodynamic properties were performed by the HF and DFT methods.

  14. Dual-Band Feed for a Microwave Reflector Antenna

    NASA Technical Reports Server (NTRS)

    Hoppe, Daniel; Reilly, Harry

    2005-01-01

    A waveguide feed has been designed to provide specified illumination patterns for a dual-reflector antenna in two wavelength bands: 8 to 9 GHz and 30 to 40 GHz. The feed (see figure) has a coaxial configuration: A wider circular tube surrounds a narrower circular tube that serves as a waveguide for the signals in the 30-to-40-GHz band. The annular space between the narrower and the wider tube serves as a coaxial waveguide for the signals in the 8-to-9-GHz band. The nominal design frequencies of the outer and inner waveguides are 8.45 and 32 GHz, respectively. Each of the two waveguides is terminated in a component that is sized and shaped to help focus the radiation in its respective frequency band into the specified illumination pattern. For the outer waveguide, the beam-shaping termination is a corrugated horn; for the inner waveguide, the beam-shaping termination is a dielectric rod insert.

  15. An ISM 2.4 GHz low power low-IF RF receiver front-end

    NASA Astrophysics Data System (ADS)

    Heping, Ma; Hua, Xu; Bei, Chen; Yin, Shi

    2015-08-01

    This paper describes the implementation of an RF receiver front-end for the 2.4 GHz industrial scientific medical band under TSMC 0.13 μm CMOS technology; it comprises a low noise amplifier (LNA) which uses an added gate-source capacitor for low power performance and a dual-converter composed of a single-balanced active RF mixer and double-balanced passive IF mixer. Dual-down-conversion technique is used for reducing power. A 2.4 GHz low power low-IF RF receiver front-end is proposed. An LNA for rejecting image signal, an inductor-capacitor (LC) tank is used in series with source of input-stage transistor of the RF mixer, and combined with the LC load of the LNA, 30-dB image rejection is realized. Fabricated in a 0.13 μm CMOS process, the proposed chip occupies 0.42 mm2 area, achieves 4 dB noise figure, -22 dBm IIP3 and 37 dB voltage gain dissipating only 4.2-mW under 1.2-V supply.

  16. 78 FR 36684 - 4.9 GHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-19

    ... Federal Register of Wednesday, August 1, 2012 (77 FR 45503). The regulations related to bandwidths of certain frequencies. DATES: Effective June 19, 2013. ADDRESSES: Federal Communications Commission, 445.... Need for Correction The Federal Register at 77 FR 45507 inadvertently listed a value of ``1'' for...

  17. 77 FR 62480 - 4.9 GHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-15

    ... comment and reply comment periods. SUMMARY: The Public Safety and Homeland Security Bureau on its own... comment and reply dates for the proposed rule published at 77 FR 45558 (August 1, 2012), are reopened... SUPPLEMENTARY INFORMATION section of this document. FOR FURTHER INFORMATION CONTACT: Thomas Eng, Policy...

  18. Two-Stage, 90-GHz, Low-Noise Amplifier

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene A.; Gaier, Todd C.; Xenos, Stephanie; Soria, Mary M.; Kangaslahti, Pekka P.; Cleary, Kieran A.; Ferreira, Linda; Lai, Richard; Mei, Xiaobing

    2010-01-01

    A device has been developed for coherent detection of the polarization of the cosmic microwave background (CMB). A two-stage amplifier has been designed that covers 75-110 GHz. The device uses the emerging 35-nm InP HEMT technology recently developed at Northrop Grumman Corporation primarily for use at higher frequencies. The amplifier has more than 18 dB gain and less than 35 K noise figure across the band. These devices have noise less than 30 K at 100 GHz. The development started with design activities at JPL, as well as characterization of multichip modules using existing InP. Following processing, a test campaign was carried out using single-chip modules at 100 GHz. Successful development of the chips will lead to development of multichip modules, with simultaneous Q and U Stokes parameter detection. This MMIC (monolithic microwave integrated circuit) amplifier takes advantage of performance improvements intended for higher frequencies, but in this innovation are applied at 90 GHz. The large amount of available gain ultimately leads to lower possible noise performance at 90 GHz.

  19. A 77-118 GHz RESONANCE-FREE SEPTUM POLARIZER

    SciTech Connect

    Chen, Yen-Lin; Chiueh, Tzihong; Teng, Hsiao-Feng

    2014-03-01

    Measurements of polarized radiation often reveal specific physical properties of emission sources, such as the strengths and orientations of magnetic fields offered by synchrotron radiation and Zeeman line emission, and the electron density distribution caused by free-free emission. Polarization-capable, millimeter/sub-millimeter telescopes are normally equipped with either septum polarizers or ortho-mode transducers (OMT) to detect polarized radiation. Though the septum polarizer is limited to a significantly narrower bandwidth than the OMT, it possesses advantageous features unparalleled by the OMT when it comes to determining astronomical polarization measurements. We design an extremely wide-band circular waveguide septum polarizer, covering 42% bandwidth, from 77 GHz to 118 GHz, without any undesired resonance, challenging the conventional bandwidth limit. Stokes parameters, constructed from the measured data between 77 GHz and 115 GHz, show that the leakage from I to Q and U is below ±2%, and the Q – U mutual leakage is below ±1%. Such a performance is comparable to other modern polarizers, but the bandwidth of this polarizer can be at least twice as wide. This extremely wide-band design removes the major weakness of the septum polarizer and opens up a new window for future astronomical polarization measurements.

  20. A 77-118 GHz Resonance-free Septum Polarizer

    NASA Astrophysics Data System (ADS)

    Chen, Yen-Lin; Chiueh, Tzihong; Teng, Hsiao-Feng

    2014-03-01

    Measurements of polarized radiation often reveal specific physical properties of emission sources, such as the strengths and orientations of magnetic fields offered by synchrotron radiation and Zeeman line emission, and the electron density distribution caused by free-free emission. Polarization-capable, millimeter/sub-millimeter telescopes are normally equipped with either septum polarizers or ortho-mode transducers (OMT) to detect polarized radiation. Though the septum polarizer is limited to a significantly narrower bandwidth than the OMT, it possesses advantageous features unparalleled by the OMT when it comes to determining astronomical polarization measurements. We design an extremely wide-band circular waveguide septum polarizer, covering 42% bandwidth, from 77 GHz to 118 GHz, without any undesired resonance, challenging the conventional bandwidth limit. Stokes parameters, constructed from the measured data between 77 GHz and 115 GHz, show that the leakage from I to Q and U is below ±2%, and the Q - U mutual leakage is below ±1%. Such a performance is comparable to other modern polarizers, but the bandwidth of this polarizer can be at least twice as wide. This extremely wide-band design removes the major weakness of the septum polarizer and opens up a new window for future astronomical polarization measurements.

  1. Development of 20 GHz monolithic transmit modules

    NASA Technical Reports Server (NTRS)

    Higgins, J. A.

    1988-01-01

    The history of the development of a transmit module for the band 17.7 to 20.2 GHz is presented. The module was to monolithically combine, on one chip, five bits of phase shift, a buffer amplifier and a power amplifier to produce 200 mW to the antenna element. The approach taken was MESFET ion implanted device technology. A common pinch-off voltage was decided upon for each application. The beginning of the total integration phases revealed hitherto unencountered hazards of large microwave circuit integration which were successfully overcome. Yield and customer considerations finally led to two separate chips, one containing the power amplifiers and the other containing the complete five bit phase shifter.

  2. Design of a 140 GHz, 100 W Gyroklystron Amplifier

    NASA Astrophysics Data System (ADS)

    Joye, Colin; Shapiro, Michael; Sirigiri, Jagadishwar; Temkin, Richard

    2004-11-01

    We present the design and the simulation results for a 140 GHz, 100 watt CW gyroklystron amplifier for use in Dynamic Nuclear Polarization (DNP) experiments. The amplifier was designed for a 15 kV, 150 mA annular electron beam and simulations show a saturated gain of 36 dB at a pitch factor of 1.5 for the TE02 mode with an efficiency of 6% and output power of 130 watts. The -3dB bandwidth is 1 GHz (0.7%) and 1.2 GHz of bandwidth is available at the 50-watt level. This design is also capable of emitting pulses on the nanosecond scale. The circuit consists of an input cavity, three bunching cavities and an output cavity with a nonlinear uptaper. This project is supported by NIBIB grant #5R01EB1965.

  3. Dual-Band Operation of a Microstrip Patch Antenna on a Duroid 5870 Substrate for Ku- and K-Bands

    PubMed Central

    Islam, M. M.; Islam, M. T.; Faruque, M. R. I.

    2013-01-01

    The dual-band operation of a microstrip patch antenna on a Duroid 5870 substrate for Ku- and K-bands is presented. The fabrication of the proposed antenna is performed with slots and a Duroid 5870 dielectric substrate and is excited by a 50 Ω microstrip transmission line. A high-frequency structural simulator (HFSS) is used which is based on the finite element method (FEM) in this research. The measured impedance bandwidth (2 : 1 VSWR) achieved is 1.07 GHz (15.93 GHz–14.86 GHz) on the lower band and 0.94 GHz (20.67–19.73 GHz) on the upper band. A stable omnidirectional radiation pattern is observed in the operating frequency band. The proposed prototype antenna behavior is discussed in terms of the comparisons of the measured and simulated results. PMID:24385878

  4. Passive 350 GHz Video Imaging Systems for Security Applications

    NASA Astrophysics Data System (ADS)

    Heinz, E.; May, T.; Born, D.; Zieger, G.; Anders, S.; Zakosarenko, V.; Meyer, H.-G.; Schäffel, C.

    2015-10-01

    Passive submillimeter-wave imaging is a concept that has been in the focus of interest as a promising technology for personal security screening for a number of years. In contradiction to established portal-based millimeter-wave scanning techniques, it allows for scanning people from a distance in real time with high throughput and without a distinct inspection procedure. This opens up new possibilities for scanning, which directly address an urgent security need of modern societies: protecting crowds and critical infrastructure from the growing threat of individual terror attacks. Considering the low radiometric contrast of indoor scenes in the submillimeter range, this objective calls for an extremely high detector sensitivity that can only be achieved using cooled detectors. Our approach to this task is a series of passive standoff video cameras for the 350 GHz band that represent an evolving concept and a continuous development since 2007. Arrays of superconducting transition-edge sensors (TES), operated at temperatures below 1 K, are used as radiation detectors. By this means, background limited performance (BLIP) mode is achieved, providing the maximum possible signal to noise ratio. At video rates, this leads to a temperature resolution well below 1 K. The imaging system is completed by reflector optics based on free-form mirrors. For object distances of 5-25 m, a field of view up to 2 m height and a diffraction-limited spatial resolution in the order of 1-2 cm is provided. Opto-mechanical scanning systems are part of the optical setup and capable of frame rates of up to 25 frames per second.

  5. An inductorless CMOS programmable-gain amplifier with a > 3 GHz bandwidth for 60 GHz wireless transceivers

    NASA Astrophysics Data System (ADS)

    Wei, Zhu; Baoyong, Chi; Lixue, Kuang; Wen, Jia; Zhihua, Wang

    2014-10-01

    An inductorless wideband programmable-gain amplifier (PGA) for 60 GHz wireless transceivers is presented. To attain wideband characteristics, a modified Cherry—Hooper amplifier with a negative capacitive neutralization technique is employed as the gain cell while a novel circuit technique for gain adjustment is adopted; this technique can be universally applicable in wideband PGA design and greatly simplifying the design of wideband PGA. By cascading two gain cells and an output buffer stage, the PGA achieves the highest gain of 30 dB with the bandwidth much wider than 3 GHz. The PGA has been integrated into one whole 60 GHz wireless transceiver and implemented in the TSMC 65 nm CMOS process. The measurements on the receiver front-end show that the receiver front-end achieves an 18 dB variable gain range with a > 3 GHz bandwidth, which proves the proposed PGA achieves an 18 dB variable gain range with a bandwidth much wider than 3 GHz. The PGA consumes 10.7 mW of power from a 1.2-V supply voltage with a core area of only 0.025 mm2.

  6. A 20 GHz bright sample for δ > 72° - II. Multifrequency follow-up

    NASA Astrophysics Data System (ADS)

    Ricci, R.; Righini, S.; Verma, R.; Prandoni, I.; Carretti, E.; Mack, K.-H.; Massardi, M.; Procopio, P.; Zanichelli, A.; Gregorini, L.; Mantovani, F.; Gawroński, M. P.; Peel, M. W.

    2013-11-01

    We present follow-up observations at 5, 8 and 30 GHz of the K-band Northern Wide Survey (KNoWS) 20 GHz Bright Sample, performed with the 32-m Medicina radio telescope and the 32-m Toruń radio telescope. The KNoWS sources were selected in the Northern Polar Cap (δ > 72°) and have a flux density limit S20 GHz = 115 mJy. We include NRAO-VLA Sky Survey 1.4 GHz measurements to derive the source radio spectra between 1.4 and 30 GHz. Based on optical identifications, 68 per cent of the sources are quasars and 27 per cent are radio galaxies. A redshift measurement is available for 58 per cent of the sources. The radio spectral properties of the different source populations are found to be in agreement with those of other high-frequency-selected samples.

  7. Cross-impact study of foreign satellite communications on NASA's 30/20 GHz program

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A comprehensive traffic demand forecast and a scenario for the transition process from current satellite systems to more advanced systems of the 1990's are presented. Systems configurations with and without the use of 30/20 GHz are described and these two alternatives are compared. It is concluded that: (1) the use of 30/20 GHz will result in increased satellite capacity, which will be needed to satisfy demand; (2) the use of 30/20 GHz will decrease the transmission cost, especially for broadband communications; (3) in some areas, particularly Europe and Japan but also the U.S., 30/20 GHz is the only available frequency band for customer premise Earth stations because of the dense terrestrial microwave networks; and (4) the development of 30/20 GHz technology will improve U.S. markets for equipment and satellites in many world regions.

  8. Circularly polarized triple band glass shaped monopole patch antenna with metallic reflector for bluetooth & wireless applications

    NASA Astrophysics Data System (ADS)

    Jangid, K. G.; Choudhary, N.; Jain, P.; Sharma, B. R.; Saini, J. S.; Kulhar, V. S.; Bhatnagar, D.

    2016-03-01

    This paper presents the design and performance of strip line fed glass shaped monopole patch antenna having with overall size 30mm × 30 mm × 1.59 mm. In the patch; an eight shaped slot and in the ground plane an eight shaped ring are introduced. A metallic ground plane is also introduced at appropriate location beneath the ground plane. The proposed antenna is simulated by applying CST Microwave Studio simulator. Antenna provides circularly polarized radiations, triple broad impedance bandwidth of 203MHz (2.306GHz to 2.510GHz), 42MHz (2.685GHz to 2.757GHz) & GHz (3.63 GHz to 6.05 GHz), high flat gain (close to 5dBi) and good radiation properties in the desired frequency range. This antenna may be a very useful tool for 2.45GHz Bluetooth communication band as well as for 2.4GHz/5.2 GHz /5.8 GHz WLAN bands & 3.7GHz/5.5 GHz Wi-Max bands.

  9. Band-notched reconfigurable CPW-fed UWB antenna

    NASA Astrophysics Data System (ADS)

    Majid, H. A.; Rahim, M. K. A.; Hamid, M. R.; Murad, N. A.; Samsuri, N. A.; Yusof, M. F. M.; Kamarudin, M. R.

    2016-04-01

    A reconfigurable band-notched CPW-fed UWB antenna using electromagnetic bandgap (EBG) structure is proposed. Two structures are positioned adjacent to the transmission line of the UWB antenna. The band-notched characteristic can be disabled by switching the state of switch place at the strip line. The EBG structure produces reconfigurable band notched at 4.0 GHz, which covers C-band satellite communication (3.625-4.2 GHz) systems. The proposed antenna is suitable for UWB systems, which requires reconfigurable band reject function.

  10. 1,2-Dichloropropane

    Integrated Risk Information System (IRIS)

    1,2 - Dichloropropane ; CASRN 78 - 87 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  11. 1,2-Dichloroethane

    Integrated Risk Information System (IRIS)

    1,2 - Dichloroethane ; CASRN 107 - 06 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  12. 1,2-Diphenylhydrazine

    Integrated Risk Information System (IRIS)

    1,2 - Diphenylhydrazine ; CASRN 122 - 66 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcin

  13. 1,2-Dichlorobenzene

    Integrated Risk Information System (IRIS)

    1,2 - Dichlorobenzene ; CASRN 95 - 50 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  14. 1,2-Dibromoethane

    Integrated Risk Information System (IRIS)

    1,2 - Dibromoethane ; CASRN 106 - 93 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogen

  15. A 150 GHz Receiver Module for Astronomical Observations

    NASA Astrophysics Data System (ADS)

    Voll, Patricia; Lau, J.; Sieth, M.; Church, S.; Samoska, L. A.; Kangaslahti, P. P.; Soria, M.; Gaier, T. C.; Van Winkle, D.; Tantawi, S.

    2011-01-01

    A compact, wide-band, heterodyne amplifier module has been designed to operate in the 150 GHz atmospheric window using High Electron Mobility Transistor (HEMT) amplifier technology. This frequency range is important for many astrophysical science applications, including spectral line studies, separating the cosmic microwave background (CMB) radiation from foregrounds, and detecting the hot gas around galaxy clusters using the Sunyaev-Zeldovich effect. HEMT-based receiver arrays with excellent noise and scalability are already being manufactured around 100 GHz, but recent advances have made it possible to extend this technology to even higher frequencies. The prototype 150 GHz module housing utilizes Monolithic Millimeter-Wave Integrated Circuit (MMIC) InP Low Noise Amplifiers (LNAs). These amplifiers, along with a second harmonic mixer, bias circuitry, and connectors, are contained in a single, split-block housing approximately one inch cubed in size. Preliminary cryogenic tests have measured a system noise temperature of 150 K over a bandwidth of 25 GHz with a minimum noise temperature of less than 100 K at 168 GHz. The minimum noise temperature is less than 100 K at 168 GHz. Module improvements for the second phase are expected to reduce the noise temperature to the minimum allowed by the device limit. Development of a 4-element array to demonstrate the scalability of these receivers is currently underway, and will serve as a prototype for much larger, 100-element arrays for astrophysical applications. In the future, a space mission incorporating an array of these modules could be used to detect the curl modes (B-modes) of the CMB polarization, which is important for the search for the signature of inflation.

  16. A 4 GHz digital receiver using the Uniboard platform

    NASA Astrophysics Data System (ADS)

    Comoretto, Giovanni; Russo, Antonietta; Quertier, Benjamin; Cais, Philippe; Camino, Pascal

    2012-09-01

    The Uniboard is a general purpose board, developed as a part of the Radionet FP7 program, that hosts 8 Altera StratixIV FPGAs interconnected by high speed links. It can be used standalone or as a part of a more complex system. The Digital receiver application uses a single Uniboard to implement a flexible packetization of a wideband signal in the frequency domain. It accepts a 4 GHz (8 GS/s) input bandwidth and provides up to 64 output bands. The bandwidth and position of each output band can be independently adjusted. The input signal is first analyzed by a polyphase filterbank, that splits the input band into 32 sub-bands with a bandwidth of 190 MHz and a spacing of 128 MHz. The overlap among adjacent bands allows the positioning of the output bands without dead regions. This filterbank is followed by an array of digitally defined downconverters, each one composed of a mixer/LO and a variable decimation filter. The filter band can be adjusted in binary steps from 1 to 128 MHz. Using tap recirculation, the filter shape remains constant over this whole range, with about 60 dB of stopband rejection and 90% usable passband. The output bands are packetized according to the VDIF VLBI standard, over eight 10G Ethernet links. Further processing can be done either on board, or in a cluster of conventional PCs. In addition, high speed ADC are in-house developed (ASIC 65nm CMOS STmicroelectronics) to feed the Uniboard card with 8GS/s, 4GHz BW, 3bits samples.

  17. High Efficiency Power Combining of Ka-Band TWTs for High Data Rate Communications

    NASA Technical Reports Server (NTRS)

    Wintucky, E. G.; Simons, R. N.; Vaden, K. R.; Lesny, G. G.; Glass, J. L.

    2006-01-01

    Future NASA deep space exploration missions are expected in some cases to require telecommunication systems capable of operating at very high data rates (potentially 1 Gbps or more) for the transmission back to Earth of large volumes of scientific data, which means high frequency transmitters with large bandwidth. Among the Ka band frequencies of interest are the present 500 MHz Deep Space Network (DSN) band of 31.8 to 32.3 GHz and a broader band at 37-38 GHz allocated for space science [1]. The large distances and use of practical antenna sizes dictate the need for high transmitter power of up to 1 kW or more. High electrical efficiency is also a requirement. The approach investigated by NASA GRC is a novel wave guide power combiner architecture based on a hybrid magic-T junction for combining the power output from multiple TWTs [1,2]. This architecture was successfully demonstrated and is capable of both high efficiency (90-95%, depending on frequency) and high data rate transmission (up to 622 Mbps) in a two-way power combiner circuit for two different pairs of Ka band TWTs at two different frequency bands. One pair of TWTs, tested over a frequency range of 29.1 to 29.6 GHz, consisted of two 110-115W TWTs previously used in uplink data transmission evaluation terminals in the NASA Advanced Communications Technology Satellite (ACTS) program [1,2]. The second pair was two 100W TWTs (Boeing 999H) designed for high efficiency operation (greater than 55%) over the DSN frequency band of 31.8 to 32.3 GHz [3]. The presentation will provide a qualitative description of the wave guide circuit, results for power combining and data transmission measurements, and results of computer modeling of the magic-T and alternative hybrid junctions for improvements in efficiency and power handling capability. The power combiner results presented here are relevant not only to NASA deep space exploration missions, but also to other U.S. Government agency programs.

  18. A survey of 44-GHz Class I methanol masers toward High Mass Protostellar Objects

    NASA Astrophysics Data System (ADS)

    Berenice Rodríguez Garza, Carolina; Kurtz, Stan

    2016-01-01

    We present preliminary results of 44-GHz Class I methanol maser observations made with the Very Large Array toward a sample of 55 High Mass Protostellar Objects. We found a 44% detection rate of methanol maser emission. We present a statistical description of our results, along with a comparison of the location of the 44-GHz masers with respect to shocked gas, traced by Extended Green Objects seen in the Spitzer/IRAC bands.

  19. The Cosmology Large Angular Scale Surveyor (CLASS): 38 GHz Detector Array of Bolometric Polarimeters

    NASA Technical Reports Server (NTRS)

    Appel, John W.; Ali, Aamir; Amiri, Mandana; Araujo, Derek; Bennett, Charles L.; Boone, Fletcher; Chan, Manwei; Cho, Hsiao-Mei; Chuss, David T.; Colazo, Felipe; Crowe, Erik; Denis, Kevin; Dunner, Rolando; Eimer, Joseph; Essinger-Hileman, Thomas; Gothe, Dominik; Halpern, Mark; Harrington, Kathleen; Kogut, Alan J..; Miller, Nathan; Moseley, Samuel H.; Stevenson, Thomas; Towner, Deborah; U-Yen, Kongpop; Wollack, Edward

    2014-01-01

    The Cosmology Large Angular Scale Surveyor (CLASS) experiment aims to map the polarization of the Cosmic Microwave Background (CMB) at angular scales larger than a few degrees. Operating from Cerro Toco in the Atacama Desert of Chile, it will observe over 65% of the sky at 38, 93, 148, and 217 GHz. In this paper we discuss the design, construction, and characterization of the CLASS 38 GHz detector focal plane, the first ever Q-band bolometric polarimeter array.

  20. Transit-time devices as local oscillators for frequencies above 100 GHz

    NASA Technical Reports Server (NTRS)

    Eisele, H.; Kidner, C.; Haddad, G. I.

    1992-01-01

    Very promising preliminary experimental results have been obtained from GaAs IMPATT diodes at F-band frequencies (75 mW, 3.5 percent at 111.1 GHz and 20 mW, 1.4 percent at 120.6 GHz) and from GaAs TUNNETT diodes at W-band frequencies (26 mW, 1.6 percent at 87.2 GHz and 32 mW, 2.6 percent at 93.5 GHz). These results indicate that IMPATT, MITATT and TUNNETT diodes have the highest potential of delivering significant amounts of power at Terahertz frequencies. As shown recently, the noise performance of GaAs W-band IMPATT diodes can compete with that of Gunn devices. Since TUNNETT diodes take advantage of the quieter tunnel injection, they are expected to be especially suited for low-noise local oscillators. This paper will focus on the two different design principles for IMPATT and TUNNETT diodes, the material parameters involved in the design and some aspects of the present device technology. Single-drift flat-profile GaAs D-band IMPATT diodes had oscillations up to 129 GHz with 9 mW, 0.9 percent at 128.4 GHz. Single-drift GaAs TUNNETT diodes had oscillations up to 112.5 GHz with 16 mW and output power levels up to 33 mW and efficiencies up to 3.4 percent around 102 GHz. These results are the best reported so far from GaAs IMPATT and TUNNETT diodes.

  1. Generation of 14 GHz radiation using a two frequency iodine laser

    NASA Astrophysics Data System (ADS)

    Nicholson, J. W.; Rudolph, W.; Hager, G.

    1998-06-01

    A mode-locked and gain-switched photolytic iodine laser Zeeman tuned to operate simultaneously on the two strongest hyperfine transitions is shown to emit 1.315 μm radiation modulated at 13.9 GHz. The interaction of this laser radiation with suitable targets leads to the generation of microwave pulses that consist of only a few cycles at 13.9 GHz, making the system attractive for ultra-wide-band, short pulse radar applications.

  2. Medium power amplifiers covering 90 - 130 GHz for telescope local oscillators

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene A.; Bryerton, Eric; Pukala, David; Peralta, Alejandro; Hu, Ming; Schmitz, Adele

    2005-01-01

    This paper describes a set of power amplifier (PA) modules containing InP High Electron Mobility Transistor (HEMT) Monolithic Millimeter-wave Integrated Circuit (MMIC) chips. The chips were designed and optimized for local oscillator sources in the 90-130 GHz band for the Atacama Large Millimeter Array telescope. The modules feature 20-45 mW of output power, to date the highest power from solid state HEMT MMIC modules above 110 GHz.

  3. The design and evaluation of a 5.8 ghz laptop-based radar system

    NASA Astrophysics Data System (ADS)

    Teng, Kevin Chi-Ming

    This project involves design and analysis of a 5.8 GHz laptop-based radar system. The radar system measures Doppler, ranging and forming Synthetic Aperture Radar (SAR) images utilizing Matlab software provided from MIT Open Courseware and performs data acquisition and signal processing. The main purpose of this work is to bring new perspective to the existing radar project by increasing the ISM band frequency from 2.4 GHz to 5.8 GHz and to carry out a series of experiments on the implementation of the radar kit. Demonstrating the radar at higher operating frequency is capable of providing accurate data results in Doppler, ranging and SAR images.

  4. The 4.8 GHz LHC Schottky pick-up system

    SciTech Connect

    Caspers, Fritz; Jimenez, Jose Miguel; Jones, Rhodri Owain; Kroyer, Tom; Vuitton, Christophe; Hamerla, Timothy W.; Jansson, Andreas; Misek, Joel; Pasquinelli, Ralph J.; Seifrid, Peter; Sun, Ding; /Fermilab

    2007-06-01

    The LHC Schottky observation system is based on traveling wave type high sensitivity pickup structures operating at 4.8 GHz. The choice of the structure and operating frequency is driven by the demanding LHC impedance requirements, where very low impedance is required below 2 GHz, and good sensitivity at the selected band at 4.8 GHz. A sophisticated filtering and triple down -mixing signal processing chain has been designed and implemented in order to achieve the specified 100 dB instantaneous dynamic range without range switching. Detailed design aspects for the complete systems and test results without beam are presented and discussed.

  5. Continuously Tunable 250 GHz Gyrotron with a Double Disk Window for DNP-NMR Spectroscopy

    PubMed Central

    Jawla, Sudheer; Ni, Qing Zhe; Barnes, Alexander; Guss, William; Daviso, Eugenio; Herzfeld, Judith; Griffin, Robert; Temkin, Richard

    2012-01-01

    In this paper, we describe the design and experimental results from the rebuild of a 250 GHz gyrotron used for Dynamic Nuclear Polarization enhanced Nuclear Magnetic Resonance spectroscopy on a 380 MHz spectrometer. Tuning bandwidth of approximately 2 GHz is easily achieved at a fixed magnetic field of 9.24 T and a beam current of 95 mA producing an average output power of >10 W over the entire tuning band. This tube incorporates a double disk output sapphire window in order to maximize the transmission at 250.58 GHz. DNP Signal enhancement of >125 is achieved on a 13C-Urea sample using this gyrotron. PMID:23539422

  6. A 3 to 6 GHz microwave/photonic transceiver for phased-array interconnects

    NASA Astrophysics Data System (ADS)

    Ackerman, Edward; Wanuga, Stephen; Candela, Karen; Scotti, Ronald E.; MacDonald, V. W.; Gates, John V.

    1992-04-01

    The general design and operation of a microwave/photonic transceiver operating in the range 3-6 GHz are presented. The transceiver consists of drop-in submodules with optical fiber pigtails mounted on a brass carrier measuring less than 1 x 1 x 0.1 inch along with MMIC amplifiers and an alumina motherboard. Minimum 3 to 6 GHz return losses of 6 dB have been measured for both the microwave input and the microwave output of the module; the insertion loss is between 19 and 20 dB at most frequencies in the 3-6 GHz band.

  7. Continuously Tunable 250 GHz Gyrotron with a Double Disk Window for DNP-NMR Spectroscopy.

    PubMed

    Jawla, Sudheer; Ni, Qing Zhe; Barnes, Alexander; Guss, William; Daviso, Eugenio; Herzfeld, Judith; Griffin, Robert; Temkin, Richard

    2013-01-01

    In this paper, we describe the design and experimental results from the rebuild of a 250 GHz gyrotron used for Dynamic Nuclear Polarization enhanced Nuclear Magnetic Resonance spectroscopy on a 380 MHz spectrometer. Tuning bandwidth of approximately 2 GHz is easily achieved at a fixed magnetic field of 9.24 T and a beam current of 95 mA producing an average output power of >10 W over the entire tuning band. This tube incorporates a double disk output sapphire window in order to maximize the transmission at 250.58 GHz. DNP Signal enhancement of >125 is achieved on a (13)C-Urea sample using this gyrotron. PMID:23539422

  8. Continuously Tunable 250 GHz Gyrotron with a Double Disk Window for DNP-NMR Spectroscopy

    NASA Astrophysics Data System (ADS)

    Jawla, Sudheer; Ni, Qing Zhe; Barnes, Alexander; Guss, William; Daviso, Eugenio; Herzfeld, Judith; Griffin, Robert; Temkin, Richard

    2013-01-01

    In this paper, we describe the design and experimental results from the rebuild of a 250 GHz gyrotron used for Dynamic Nuclear Polarization enhanced Nuclear Magnetic Resonance spectroscopy on a 380 MHz spectrometer. Tuning bandwidth of approximately 2 GHz is easily achieved at a fixed magnetic field of 9.24 T and a beam current of 95 mA producing an average output power of >10 W over the entire tuning band. This tube incorporates a double disk output sapphire window in order to maximize the transmission at 250.58 GHz. DNP Signal enhancement of >125 is achieved on a 13C-Urea sample using this gyrotron.

  9. MMIC DHBT Common-Base Amplifier for 172 GHz

    NASA Technical Reports Server (NTRS)

    Paidi, Vamsi; Griffith, Zack; Wei, Yun; Dahlstrom, Mttias; Urteaga, Miguel; Rodwell, Mark; Samoska, Lorene; Fung, King Man; Schlecht, Erich

    2006-01-01

    Figure 1 shows a single-stage monolithic microwave integrated circuit (MMIC) power amplifier in which the gain element is a double-heterojunction bipolar transistor (DHBT) connected in common-base configuration. This amplifier, which has been demonstrated to function well at a frequency of 172 GHz, is part of a continuing effort to develop compact, efficient amplifiers for scientific instrumentation, wide-band communication systems, and radar systems that will operate at frequencies up to and beyond 180 GHz. The transistor is fabricated from a layered structure formed by molecular beam epitaxy in the InP/InGaAs material system. A highly doped InGaAs base layer and a collector layer are fabricated from the layered structure in a triple mesa process. The transistor includes two separate emitter fingers, each having dimensions of 0.8 by 12 m. The common-base configuration was chosen for its high maximum stable gain in the frequency band of interest. The input-matching network is designed for high bandwidth. The output of the transistor is matched to a load line for maximum saturated output power under large-signal conditions, rather than being matched for maximum gain under small-signal conditions. In a test at a frequency of 172 GHz, the amplifier was found to generate an output power of 7.5 mW, with approximately 5 dB of large-signal gain (see Figure 2). Moreover, the amplifier exhibited a peak small-signal gain of 7 dB at a frequency of 176 GHz. This performance of this MMIC single-stage amplifier containing only a single transistor represents a significant advance in the state of the art, in that it rivals the 170-GHz performance of a prior MMIC three-stage, four-transistor amplifier. [The prior amplifier was reported in "MMIC HEMT Power Amplifier for 140 to 170 GHz" (NPO-30127), NASA Tech Briefs, Vol. 27, No. 11 (November 2003), page 49.] This amplifier is the first heterojunction- bipolar-transistor (HBT) amplifier built for medium power operation in this

  10. A 12 GHz RF Power Source for the CLIC Study

    SciTech Connect

    Schirm, Karl; Curt, Stephane; Dobert, Steffen; McMonagle, Gerard; Rossat, Ghislain; Syratchev, Igor; Timeo, Luca; Haase, Andrew Jensen, Aaron; Jongewaard, Erik; Nantista, Christopher; Sprehn, Daryl; Vlieks, Arnold; Hamdi, Abdallah; Peauger, Franck; Kuzikov, Sergey; Vikharev, Alexandr; /Nizhnii Novgorod, IAP

    2012-07-03

    The CLIC RF frequency has been changed in 2008 from the initial 30 GHz to the European X-band 11.9942 GHz permitting beam independent power production using klystrons for CLIC accelerating structure testing. A design and fabrication contract for five klystrons at that frequency has been signed by different parties with SLAC. France (IRFU, CEA Saclay) is contributing a solid state modulator purchased in industry and specific 12 GHz RF network components to the CLIC study. RF pulses over 120 MW peak at 230 ns length will be obtained by using a novel SLED-I type pulse compression scheme designed and fabricated by IAP, Nizhny Novgorod, Russia. The X-band power test stand is being installed in the CLIC Test Facility CTF3 for independent structure and component testing in a bunker, but allowing, in a later stage, for powering RF components in the CTF3 beam lines. The design of the facility, results from commissioning of the RF power source and the expected performance of the Test Facility are reported.

  11. Room-Temperature Electron Spin Relaxation of Triarylmethyl Radicals at the X- and Q-Bands.

    PubMed

    Kuzhelev, Andrey A; Trukhin, Dmitry V; Krumkacheva, Olesya A; Strizhakov, Rodion K; Rogozhnikova, Olga Yu; Troitskaya, Tatiana I; Fedin, Matvey V; Tormyshev, Victor M; Bagryanskaya, Elena G

    2015-10-29

    Triarylmethyl radicals (trityls, TAMs) represent a relatively new class of spin labels. The long relaxation of trityls at room temperature in liquid solutions makes them a promising alternative for traditional nitroxides. In this work we have synthesized a series of TAMs including perdeuterated Finland trityl (D36 form), mono-, di-, and triester derivatives of Finland-D36 trityl, the deuterated form of OX63, the dodeca-n-butyl homologue of Finland trityl, and triamide derivatives of Finland trityl with primary and secondary amines attached. We have studied room-temperature relaxation properties of these TAMs in liquids using pulsed electron paramagnetic resonance (EPR) at two microwave frequency bands. We have found the clear dependence of phase memory time (Tm ∼ T2) on the magnetic field: room-temperature Tm values are ∼1.5-2.5 times smaller at the Q-band (34 GHz, 1.2 T) than at the X-band (9 GHz, 0.3 T). This trend is ascribed to the contribution from g-anisotropy that is negligible at lower magnetic fields but comes into play at the Q-band. In agreement with this, the difference between T1 and Tm becomes more pronounced at the Q-band than at the X-band due to increased contributions from incomplete motional averaging of g-anisotropy. Linear dependence of (1/Tm - 1/T1) on viscosity implies that g-anisotropy is modulated by rotational motion of the trityl radical. On the basis of the analysis of previous data and results of the present work, we conclude that, in the general situation where the spin label is at least partly mobile, the X-band is most suitable for application of trityls for room-temperature pulsed EPR distance measurements. PMID:26001103

  12. Radio-Far-infrared Correlation in “Blue Cloud” Galaxies with 0 < z < 1.2

    NASA Astrophysics Data System (ADS)

    Basu, Aritra; Wadadekar, Yogesh; Beelen, Alexandre; Singh, Veeresh; Archana, K. N.; Sirothia, Sandeep; Ishwara-Chandra, C. H.

    2015-04-01

    We study the radio-far-infrared (FIR) correlation in “blue cloud” galaxies chosen from the PRism MUltiobject Survey up to redshift (z) of 1.2 in the XMM-LSS field. We use rest-frame emission at 1.4 GHz in the radio and both monochromatic (at 70 μm) and bolometric (between 8 and 1000 μm) emission in the FIR. To probe the nature of the correlation up to z ˜1.2, where direct detection of blue star-forming galaxies is impossible with current technology, we employ the technique of image stacking at 0.325 and 1.4 GHz in the radio and in six infrared bands, 24, 70, 160, 250, 350, and 500 μm. For comparison, we also study the correlation for more luminous galaxies that are directly detected. The stacking analysis allows us to probe the radio-FIR correlation for galaxies that are up to two orders of magnitude fainter than the ones detected directly. The k correction in the infrared wavebands is obtained by fitting the observed spectral energy distribution with a composite mid-IR power law and a single temperature graybody model. We find that the radio luminosity at 1.4 GHz ({{L}1.4 GHz}) is strongly correlated with monochromatic FIR luminosity at 70 μm ({{L}70 μ m}) having slope 1.09 ± 0.05 and with bolometric luminosity ({{L}TIR}) having slope 1.11 ± 0.04. The quantity {{q}TIR}(={{log }10}[{{L}TIR}/(3.75× {{10}12}{{L}1.4 GHz})]) is observed to decrease with redshift as {{q}TIR}\\propto {{(1+z)}-0.16+/- 0.03} probably caused due to the nonlinear slope of the radio-FIR correlation. Within the uncertainties of our measurement and the limitations of our flux-limited and color-selected sample, we do not find any evolution of the radio-FIR correlation with redshift.

  13. Optical frequency comb based multi-band microwave frequency conversion for satellite applications.

    PubMed

    Yang, Xinwu; Xu, Kun; Yin, Jie; Dai, Yitang; Yin, Feifei; Li, Jianqiang; Lu, Hua; Liu, Tao; Ji, Yuefeng

    2014-01-13

    Based on optical frequency combs (OFC), we propose an efficient and flexible multi-band frequency conversion scheme for satellite repeater applications. The underlying principle is to mix dual coherent OFCs with one of which carrying the input signal. By optically channelizing the mixed OFCs, the converted signal in different bands can be obtained in different channels. Alternatively, the scheme can be configured to generate multi-band local oscillators (LO) for widely distribution. Moreover, the scheme realizes simultaneous inter- and intra-band frequency conversion just in a single structure and needs only three frequency-fixed microwave sources. We carry out a proof of concept experiment in which multiple LOs with 2 GHz, 10 GHz, 18 GHz, and 26 GHz are generated. A C-band signal of 6.1 GHz input to the proposed scheme is successfully converted to 4.1 GHz (C band), 3.9 GHz (C band) and 11.9 GHz (X band), etc. Compared with the back-to-back (B2B) case measured at 0 dBm input power, the proposed scheme shows a 9.3% error vector magnitude (EVM) degradation at each output channel. Furthermore, all channels satisfy the EVM limit in a very wide input power range. PMID:24515046

  14. Detection of 183 GHz H2O megamaser emission towards NGC 4945

    NASA Astrophysics Data System (ADS)

    Humphreys, E. M. L.; Vlemmings, W. H. T.; Impellizzeri, C. M. V.; Galametz, M.; Olberg, M.; Conway, J. E.; Belitsky, V.; De Breuck, C.

    2016-08-01

    Aims: The aim of this work is to search Seyfert 2 galaxy NGC 4945, a well-known 22 GHz water megamaser galaxy, for H2O (mega)maser emission at 183 GHz. Methods: We used APEX SEPIA Band 5 (an ALMA Band 5 receiver on the APEX telescope) to perform the observations. Results: We detected 183 GHz H2O maser emission towards NGC 4945 with a peak flux density of ~3 Jy near the galactic systemic velocity. The emission spans a velocity range of several hundred km s-1. We estimate an isotropic luminosity of >1000 L⊙, classifying the emission as a megamaser. A comparison of the 183 GHz spectrum with that observed at 22 GHz suggests that 183 GHz emission also arises from the active galactic nucleus (AGN) central engine. If the 183 GHz emission originates from the circumnuclear disk, then we estimate that a redshifted feature at 1084 km s-1 in the spectrum should arise from a distance of 0.022 pc from the supermassive black hole (1.6 × 105 Schwarzschild radii), i.e. closer than the water maser emission previously detected at 22 GHz. This is only the second time 183 GHz maser emission has been detected towards an AGN central engine (the other galaxy being NGC 3079). It is also the strongest extragalactic millimetre/submillimetre water maser detected to date. Conclusions: Strong millimetre 183 GHz H2O maser emission has now been shown to occur in an external galaxy. For NGC 4945, we believe that the maser emission arises, or is dominated by, emission from the AGN central engine. Emission at higher velocity, i.e. for a Keplerian disk closer to the black hole, has been detected at 183 GHz compared with that for the 22 GHz megamaser. This indicates that millimetre/submillimetre H2O masers can indeed be useful for tracing out more of AGN central engine structures and dynamics than previously probed. Future observations using ALMA Band 5 should unequivocally determine the origin of the emission in this and other galaxies.

  15. The 30/20 GHz communications satellite trunking network study

    NASA Technical Reports Server (NTRS)

    Kolb, W.

    1981-01-01

    Alternative transmission media for a CONUS-wide trunking network in the years 1990 and 2000 are examined. The alternative technologies comprised fiber optic cable, conventional C- and Ku-band satellites, and 30/20 GHz satellites. Three levels of implementation were considered - a 10-city network, a 20-city network, and a 40-city network. The cities selected were the major metropolitan areas with the greatest communications demand. All intercity voice, data, and video traffic carried more than 40 miles was included in the analysis. In the optimized network, traffic transmitted less than 500 miles was found to be better served by fiber optic cable in 1990. By the year 2000, the crossover point would be down to 200 miles, assuming availability of 30/20 GHz satellites.

  16. Submillimeter Spectroscopy with a 500-1000 GHz SIS Receiver

    NASA Technical Reports Server (NTRS)

    Zmuidzinas, J.

    1997-01-01

    Sub-millimeter Spectroscopy with a 500-1000 GHz SIS Receiver, which extended over the period October 1, 1991 through January 31, 1997. The purpose of the grant was to fund the development and construction of a sensitive heterodyne receiver system for the submillimeter band (500-1000 GHz), using our newly-developed sensitive superconducting (SIS) detectors, and to carry out astronomical observations with this system aboard the NASA Kuiper Air- borne Observatory (a Lockheed C-141 aircraft carrying a 91 cm telescope). A secondary purpose of the grant was to stimulate the continued development of sensitive submillimeter detectors, in order to prepare for the next-generation airborne observatory, SOFIA, as well as future space missions (such as the ESA/NASA FIRST mission).

  17. Generating Ka-Band Signals Using an X-Band Vector Modulator

    NASA Technical Reports Server (NTRS)

    Smith, Scott; Mysoor, Narayan; Lux, James; Cook, Brian; Shah, Biren

    2009-01-01

    A breadboard version of a transmitter for radio communication at a carrier frequency of 32 GHz (which is in the Ka band) utilizes a vector modulator operating at a carrier frequency of 8 GHz (the low end of the X band) to generate any of a number of advanced modulations that could include amplitude and/or phase modulation components. The 8-GHz modulated signal is mixed with a 24-GHz signal generated by an upconverter to obtain the desired 32-GHz modulated output. The transmitter is being developed as a prototype of downlink transmitters for transmission of data from spacecraft to Earth at high rates (>100 Mb/s). The transmitter design could also be adapted to terrestrial and Earth/satellite communication links. The advanced modulations (which can include M-ary phase-shift keying (M-PSK), offset phase-shift keying (OPSK), and M-ary quadrature amplitude modulation (M-QAM). These modulations are needed because for a given amount of signal bandwidth, they enable transmission of data at rates greater than those of older, simpler modulation schemes. The transmitter architecture (see figure) was chosen not only to enable generation of the required modulations at 32 GHz but also to reduce the number of components needed to implement the transmitter. Instead of incorporating an 8-GHz signal source, the transmitter utilizes an 8-GHz signal generated by a voltage-controlled oscillator that is part of an X-band transponder with which the fully developed version of this transmitter would be used in the original intended spacecraft application. The oscillator power is divided onto two paths, one of which goes through the vector modulator, the other through amplifiers and a 3 frequency multiplier. Band-pass filters are included downstream of the frequency multiplier to suppress unwanted harmonics.

  18. A packaged Schottky diode as detector, harmonic mixer, and harmonic generator in the 25 500 GHz range

    NASA Astrophysics Data System (ADS)

    Goy, P.

    1982-03-01

    This paper describes experimental results obtained with a packaged GaAs Schottky barrier diode in contact with a coaxial connector and placed across waveguides for bands Ka, V, E, W or F. Among the microwave sources used for calibration were 9 carcinotrons in the frequency interval 51 490 GHz. As soon as the frequency F is above the waveguide cut-off frequency, the different characteristics do not depend critically on the waveguide size for V, E, W and F bands. The video detection sensitivity, of several 100 mV/mW at 50 GHz and below, decreases as F-4 in the range 51 500 GHz. Coupling an X-band centimeter frequency via the coaxial connector and a millimeter frequency via the waveguide permits harmonic mixing in the diode. Between 36 and 490 GHz, the harmonic mixing number varies from 3 up to the very large value 40 with conversion losses from 18 to 88 dB. The minimum detectable signal in the 100 kHz band can be as low as -90 dBm at 80 GHz. A noticeable millimeter power is available at the waveguide output from injected centimeter power by harmonic generation. Starting for instance with 100 mW around 11.5 GHz, we have measured 0.1 mW at 80 GHz and 0.1 μW at 230 GHz. To illustrate the possibility of creating usable millimeter and submillimeter wave without heavy equipment (such as carcinotrons or millimeter klystron) we report spectroscopic experiments in Rydberg atoms. Resonances have been observed up to 340 GHz by harmonic generation (28th harmonic) from an X-band klystron).

  19. InP MMIC Chip Set for Power Sources Covering 80-170 GHz

    NASA Technical Reports Server (NTRS)

    Ngo, Catherine

    2001-01-01

    We will present a Monolithic Millimeter-wave Integrated Circuit (MMIC) chip set which provides high output-power sources for driving diode frequency multipliers into the terahertz range. The chip set was fabricated at HRL Laboratories using a 0.1-micrometer gate-length InAlAs/InGaAs/InP high electron mobility transistor (HEMT) process, and features transistors with an f(sub max) above 600 GHz. The HRL InP HEMT process has already demonstrated amplifiers in the 60-200 GHz range. In this paper, these high frequency HEMTs form the basis for power sources up to 170 GHz. A number of state-of-the-art InP HEMT MMICs will be presented. These include voltage-controlled and fixed-tuned oscillators, power amplifiers, and an active doubler. We will first discuss an 80 GHz voltage-controlled oscillator with 5 GHz of tunability and at least 17 mW of output power, as well as a 120 GHz oscillator providing 7 mW of output power. In addition, we will present results of a power amplifier which covers the full WRIO waveguide band (75-110 GHz), and provides 40-50 mW of output power. Furthermore, we will present an active doubler at 164 GHz providing 8% bandwidth, 3 mW of output power, and an unprecedented 2 dB of conversion loss for an InP HEMT MMIC at this frequency. Finally, we will demonstrate a power amplifier to cover 140-170 GHz with 15-25 mW of output power and 8 dB gain. These components can form a power source in the 155-165 GHz range by cascading the 80 GHz oscillator, W-band power amplifier, 164 GHz active doubler and final 140-170 GHz power amplifier for a stable, compact local oscillator subsystem, which could be used for atmospheric science or astrophysics radiometers.

  20. A Novel Compact UWB Monopole Antenna with Bluetooth and Triple Notch Band

    NASA Astrophysics Data System (ADS)

    Li, Li; Zhou, Zhi-Li; Hong, Jing-Song

    2013-01-01

    A novel technique to add an extra Bluetooth band and triple notch bands simultaneously to a compact ultra-wideband (UWB) monopole antenna is presented. This scissors-shaped UWB antenna, covering 2.9 GHz-12.5 GHz, is fed by a special microstrip line. To create an extra Bluetooth band centered at 2.45 GHz, an arc-shaped stub is attached to the high concentrated current area right of the feed line and a rectangular slot is etched in the radiation patch. Besides, a notch band for WLAN (5.6 GHz-6.15 GHz) is also obtained. In addition, by connecting two asymmetric stubs to the feed line, two other notch bands in 3.28 GHz-3.8 GHz for WiMAX and 7.1 GHz-7.76 GHz for downlink of X-band satellite communication systems are achieved. The proposed antenna with compact size of 20 mm × 26 mm is fabricated and measured, showing stable antenna gain and good omni-directional radiation patterns in H-plane.

  1. A Smile Face Monopole Antenna with Quadruple Band-Notched Characteristics

    NASA Astrophysics Data System (ADS)

    Yang, Xiao-Lin; Kong, Fang-Ling; Wang, Yan

    2015-05-01

    A compact planar ultra-wideband (UWB) monopole antenna with quadruple band-notched characteristics is presented. The notched band at 3.3-4.2 GHz (C-band) is obtained by embedding a pair of Z-shaped slots on the elliptical radiation patch. Meanwhile, a modified U-shaped slot is etched in the radiation patch to create the notched band at 4.9-5.4 GHz for WLAN. In addition, by introducing E-shaped stubs on the back layer, the notched bands at 5.5-6.1 GHz for WLAN and 7-8.15 GHz for downlink of X-band satellite communication system are obtained. The antenna is fabricated and measured, showing broadband matched impedance and good Omni-directional patterns with high fidelity and phase linearity (outside the notched bands).

  2. Monolithic 20-GHz Transmitting Module

    NASA Technical Reports Server (NTRS)

    Kascak, T.; Kaelin, G.; Gupta, A.

    1986-01-01

    20-GHz monolithic microwave/millimeter-wave integrated circuit (MMIC) with amplification and phase-shift (time-delay) capabilities developed. Use of MMIC module technology promises to make feasible development of weight- and cost-effective phased-array antenna systems, identified as major factor in achieving minimum cost and efficient use of frequency and orbital resources of future generations of communication satellite systems. Use of MMIC transmitting modules provides for relatively simple method for phase-shift control of many separate radio-frequency (RF) signals required for phased-array antenna systems.

  3. Architecture for a 1-GHz Digital RADAR

    NASA Technical Reports Server (NTRS)

    Mallik, Udayan

    2011-01-01

    An architecture for a Direct RF-digitization Type Digital Mode RADAR was developed at GSFC in 2008. Two variations of a basic architecture were developed for use on RADAR imaging missions using aircraft and spacecraft. Both systems can operate with a pulse repetition rate up to 10 MHz with 8 received RF samples per pulse repetition interval, or at up to 19 kHz with 4K received RF samples per pulse repetition interval. The first design describes a computer architecture for a Continuous Mode RADAR transceiver with a real-time signal processing and display architecture. The architecture can operate at a high pulse repetition rate without interruption for an infinite amount of time. The second design describes a smaller and less costly burst mode RADAR that can transceive high pulse repetition rate RF signals without interruption for up to 37 seconds. The burst-mode RADAR was designed to operate on an off-line signal processing paradigm. The temporal distribution of RF samples acquired and reported to the RADAR processor remains uniform and free of distortion in both proposed architectures. The majority of the RADAR's electronics is implemented in digital CMOS (complementary metal oxide semiconductor), and analog circuits are restricted to signal amplification operations and analog to digital conversion. An implementation of the proposed systems will create a 1-GHz, Direct RF-digitization Type, L-Band Digital RADAR--the highest band achievable for Nyquist Rate, Direct RF-digitization Systems that do not implement an electronic IF downsample stage (after the receiver signal amplification stage), using commercially available off-the-shelf integrated circuits.

  4. 35 GHz, 4-Cavity Gyroklystron Amplifier Experiment

    NASA Astrophysics Data System (ADS)

    Garven, M.; Calame, J. P.; Danly, B. G.; Levush, B.; Wood, F.

    1998-11-01

    Gyroklystron amplifiers operating in the Ka-band are attractive sources for the next generation of millimeter wave radars and are currently under investigation at the Naval Research Laboratory (NRL). A four-cavity, 35 GHz gyroklystron experiment has been designed to demonstrate higher saturated gain (50dB) than previous experiments at NRL( J. J. Choi et al, IEEE Trans. Plasma Sci. 26(3), 416, 1998.). Non-linear, time-dependent simulations of the 4-cavity gyroklystron amplifier design using MAGYKL(P. E. Latham et al IEEE Trans. Plasma Sci. 22, 804, 1994.) predict 35% efficiency, 225 kW peak power, 50 dB saturated gain and a -3 dB bandwidth of 0.6%. For this four-cavity gyroklystron, the interaction between the TE_01 mode and a 70 kV, 9 A electron beam was studied with α=1.3 and an rms perpendicular velocity spread of 9%. Initial studies have shown that variations in magnetic field and voltage affect the trade-offs between power, bandwidth and efficiency. Theoretical design studies and experimental progress will be presented.

  5. 47 CFR 25.136 - Licensing provisions for user transceivers in the 1.6/2.4 GHz, 1.5/1.6 GHz, and 2 GHz Mobile...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the 1.6/2.4 GHz, 1.5/1.6 GHz, and 2 GHz Mobile Satellite Services. 25.136 Section 25.136 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS..., 1.5/1.6 GHz, and 2 GHz Mobile Satellite Services. In addition to the technical...

  6. Achieving Higher Energies via Passively Driven X-band Structures

    NASA Astrophysics Data System (ADS)

    Sipahi, Taylan; Sipahi, Nihan; Milton, Stephen; Biedron, Sandra

    2014-03-01

    Due to their higher intrinsic shunt impedance X-band accelerating structures significant gradients with relatively modest input powers, and this can lead to more compact particle accelerators. At the Colorado State University Accelerator Laboratory (CSUAL) we would like to adapt this technology to our 1.3 GHz L-band accelerator system using a passively driven 11.7 GHz traveling wave X-band configuration that capitalizes on the high shunt impedances achievable in X-band accelerating structures in order to increase our overall beam energy in a manner that does not require investment in an expensive, custom, high-power X-band klystron system. Here we provide the design details of the X-band structures that will allow us to achieve our goal of reaching the maximum practical net potential across the X-band accelerating structure while driven solely by the beam from the L-band system.

  7. A low power dual-band multi-mode RF front-end for GNSS applications

    NASA Astrophysics Data System (ADS)

    Hao, Zhang; Zhiqun, Li; Zhigong, Wang

    2010-11-01

    A CMOS dual-band multi-mode RF front-end for the global navigation satellite system receivers of all GPS, Bei-Dou, Galileo and Glonass systems is presented. It consists of a reconfigurable low noise amplifier (LNA), a broadband active balun, a high linearity mixer and a bandgap reference (BGR) circuit. The effect of the input parasitic capacitance on the input impedance of the inductively degenerated common source LNA is analyzed in detail. By using two different LC networks at the input port and the switched capacitor at the output port, the LNA can work at two different frequency bands (1.2 GHz and 1.5 GHz) under low power consumption. The active balun uses a hybrid-connection structure to achieve high bandwidth. The mixer uses the multiple gated transistors technique to acquire a high linearity under low power consumption but does not deteriorate other performances. The measurement results of the proposed front-end achieve a noise figure of 2.1/2.0 dB, again of 33.9/33.8 dB and an input 1-dB compression point of 0/1 dBm at 1227.6/1575.42 MHz. The power consumption is about 16 mW under a 1.8 V power supply.

  8. An 'X-banded' Tidbinbilla interferometer

    NASA Technical Reports Server (NTRS)

    Batty, Michael J.; Gardyne, R. G.; Gay, G. J.; Jauncy, David L.; Gulkis, S.; Kirk, A.

    1986-01-01

    The recent upgrading of the Tidbinbilla two-element interferometer to simultaneous S-band (2.3 GHz) and X-band (8.4 GHz) operation has provided a powerful new astronomical facility for weak radio source measurement in the Southern Hemisphere. The new X-band system has a minimum fringe spacing of 38 arcsec, and about the same positional measurement capability (approximately 2 arcsec) and sensitivity (1 s rms noise of 10 mJy) as the previous S-band system. However, the far lower confusion limit will allow detection and accurate positional measurements for sources as weak as a few millijanskys. This capability will be invaluable for observations of radio stars, X-ray sources and other weak, compact radio sources.

  9. Dual band multi frequency rectangular patch microstrip antenna with flyswatter shaped slot for wireless systems

    NASA Astrophysics Data System (ADS)

    Bhardwaj, Dheeraj; Saraswat, Shriti; Gulati, Gitansh; Shekhar, Snehanshu; Joshi, Kanika; Sharma, Komal

    2016-03-01

    In this paper a dual band planar antenna has been proposed for IEEE 802.16 Wi-MAX /IEEE 802.11 WLAN/4.9 GHz public safety applications. The antenna comprises a frequency bandwidth of 560MHz (3.37GHz-3.93GHz) for WLAN and WiMAX and 372MHz (4.82GHz-5.192GHz) for 4.9 GHz public safety applications and Radio astronomy services (4.8-4.94 GHz). The proposed antenna constitutes of a single microstrip patch reactively loaded with three identical steps positioned in a zig-zag manner towards the radiating edges of the patch. The coaxially fed patch antenna characteristics (radiation pattern, antenna gain, antenna directivity, current distribution, S11) have been investigated. The antenna design is primarily focused on achieving a dual band operation.

  10. The 18/30 GHz fixed communications system service demand assessment. Volume 2: Main text

    NASA Technical Reports Server (NTRS)

    Gabriszeski, T.; Reiner, P.; Rogers, J.; Terbo, W.

    1979-01-01

    The total demand for communications services, and satellite transmission services at the 4/6 GHz, 12/14 GHz, and 18/30 GHz frequencies is assessed. The services are voice, video, and data services. Traffic demand, by service, is distributed by geographical regions, population density, and distance between serving points. Further distribution of traffic is made among four major end user groups: business, government, institutions and private individuals. A traffic demand analysis is performed on a typical metropolitan city to examine service distribution trends. The projected cost of C and Ku band satellite systems are compared on an individual service basis to projected terrestrial rates. Separation of traffic between transmission systems, including 18/30 GHz systems, is based on cost, user, and technical considerations.

  11. Short optical pulse generation at 40 GHz with a bulk electro-absorption modulator packaged device

    NASA Astrophysics Data System (ADS)

    Langlois, Patrick; Moore, Ronald; Prosyk, Kelvin; O'Keefe, Sean; Oosterom, Jill A.; Betty, Ian; Foster, Robert; Greenspan, Jonathan; Singh, Priti

    2003-12-01

    Short optical pulse generation at 40GHz and 1540nm wavelength is achieved using fully packaged bulk quaternary electro-absorption modulator modules. Experimental results obtained with broadband and narrowband optimized packaged modules are presented and compared against empirical model predictions. Pulse duty cycle, extinction ratio and chirp are studied as a function of sinusoidal drive voltage and detuning between operating wavelength and modulator absorption band edge. Design rules and performance trade-offs are discussed. Low-chirp pulses with a FWHM of ~12ps and sub-4ps at a rate of 40GHz are demonstrated. Optical time-domain demultiplexing of a 40GHz to a 10GHz pulse train is also demonstrated with better than 20dB extinction ratio.

  12. Weather Forecasting for Ka-band Operations: Initial Study Results

    NASA Astrophysics Data System (ADS)

    Morabito, D.; Wu, L.; Slobin, S.

    2016-08-01

    As lower frequency bands (e.g., 2.3 GHz and 8.4 GHz) have become oversubscribed during the past several decades, NASA has become interested in using higher frequency bands (e.g., 26 GHz and 32 GHz) for telemetry, thus making use of the available wider bandwidth. However, these bands are more susceptible to atmospheric degradation. Currently, flight projects tend to be conservative in preparing their communications links by using worst-case or conservative assumptions. Such assumptions result in nonoptimum data return. We explore the use of weather forecasting for Goldstone and Madrid for different weather condition scenarios to determine more optimal values of atmospheric attenuation and atmospheric noise temperature for use in telecommunication link design. We find that the use of weather forecasting can provide up to 2 dB or more of increased data return when more favorable conditions are forecast. Future plans involve further developing the technique for operational scenarios with interested flight projects.

  13. 17 GHz low noise GaAs FET amplifier

    NASA Astrophysics Data System (ADS)

    Bharj, J. S.

    1984-10-01

    The considered amplifier is suitable for use as the first stage in a direct broadcast TV satellite receiver, and it was specifically designed for the Unisat spacecraft. Attention is given to RF device characterization, the design of the low-noise FET amplifier, the very significant dispersion effects at 17 GHz, the noise figure, and questions of DC bias. Balanced stages are used for low-noise and high-gain amplifiers to enhance the reliability. The noise figure of the amplifier is approximately 3.75 dB in the frequency band of interest. A low-noise microstrip GaAs FET amplifier circuit is shown.

  14. The 30/20 GHz experimental communications satellite system

    NASA Technical Reports Server (NTRS)

    Sivo, J. N.

    1981-01-01

    NASA is continuing to pursue an agressive satellite communications technology development program focused on the 30/20 GHz frequency band. A review of the program progress to date is presented. Included is a discussion of the technology program status as well as a description of the experimental system concept under study. Expected system performance characteristics together with spacecraft and payload configuration details including weight and power budget is presented. Overall program schedules of both the technology development and the flight system development are included.

  15. First demonstration of a vehicle mounted 250GHz real time passive imager

    NASA Astrophysics Data System (ADS)

    Mann, Chris

    2009-05-01

    This paper describes the design and performance of a ruggedized passive Terahertz imager, the frequency of operation is a 40GHz band centred around 250GHz. This system has been specifically targeted at vehicle mounted operation, outdoors in extreme environments. The unit incorporates temperature stabilization along with an anti-vibration chassis and is sealed to allow it to be used in a dusty environment. Within the system, a 250GHz heterodyne detector array is mated with optics and scanner to allow real time imaging out to 100 meters. First applications are envisaged to be stand-off, person borne IED detection to 30 meters but the unique properties in this frequency band present other potential uses such as seeing through smoke and fog. The possibility for use as a landing aid is discussed. A detailed description of the system design and video examples of typical imaging output will be presented.

  16. 20/30 GHz satellite systems technology needs assessment. [for domestic communications

    NASA Technical Reports Server (NTRS)

    Stevens, G.; Wright, D.

    1978-01-01

    The paper surveys the system and market work done at NASA-Lewis with regard to exploring the potential of the 20/30 GHz bands for domestic satellite communications. The 20/30 GHz bands appear attractive economically and, with certain technology advances, appear to offer a virtually unlimited spectrum resource. This attractiveness is especially relevant to high density trunking where there is sufficient traffic to justify dual-station site diversity. Ongoing system and market studies actively involve satellite system suppliers and carriers as well as the government in a cooperative, mutually beneficial effort. It is considered that this is the approach most likely to result in a spectrum-efficient acceptable-risk high-capacity 30/30 GHz satellite system which is relevant to anticipated markets.

  17. A 30-GHz Hexagonal Ferrite Phase Shifter

    NASA Astrophysics Data System (ADS)

    Semenov, A. S.; Slavin, A. N.; Mantese, J. V.

    2005-03-01

    Highly-anisotropic hexaferrites, such as barium ferrite BaFe12O19 (BFO), are ideal for millimeter wave phase shifters due to a large ferromagnetic resonance frequency at low magnetic bias field H. It enables one to make millimeter-wave devices with compact magnetic systems. Here we discuss the design, fabrication and characterization of a BFO phase shifter. A microstrip line deposited on a ferrite substrate supports the propagation of electromagnetic wave, leading to a phase shift kb, where k is the wave number and b is the length of the microstrip line. As k is a function of the bias H, we obtain a differential phase shift with a change of H. A phase shifter consisting of a single crystal (7 x 7 x 0.5 mm^3) BFO and a 500 μm wide stripline was evaluated at 30 GHz. A differential phase shift of 30 deg. was measured for H=1.2 kOe. The measured value of the insertion loss was about 10 dB. -Work supported by a grant from the Delphi Automotive Corporation.

  18. Magnetron Driven L Band RF Gun using a Photocathode Emitter

    NASA Astrophysics Data System (ADS)

    Evans, Kirk; Fisher, Amnon; Friedman, Moshe

    1996-11-01

    Magnetron Driven L Band RF Gun using a Photocathode Emitter A tunable 5 megawatt L-Band injection locked magnetron amplifier is used to drive a 1-1/2 cell RF cavity gun, to produce a 2.5 megavolt electron beam. A tunable RF source relaxes the precision of the cavity gun construction, and therefore simplifies the design and reduces the overall cost. The design of the L-Band ( 1.3 GHz) RF cavity linear accelerator is presented, along with Superfish, SOS computer simulations, and calculations of beam energy and temporal qualities. Measurements of a few robust photocathode materials as well as measurements of the beam qualities of the final accelerator are presented. Future work will utilize new semiconductor laser diodes that can be electrically driven in the gigahertz range. This makes possible an electron gun system which can run at the RF frequency used to accelerate the electron beam. Such a system produces a "lock to clock" and synchronized RF and electron beam source which can be run single shot or any rep rate up to the RF frequency.

  19. MMIC Power Amplifier Puts Out 40 mW From 75 to 110 GHz

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene

    2006-01-01

    A three-stage monolithic microwave integrated circuit (MMIC) W-band amplifier has been constructed and tested in a continuing effort to develop amplifiers as well as oscillators, frequency multipliers, and mixers capable of operating over wide frequency bands that extend above 100 GHz. There are numerous potential uses for MMICs like these in scientific instruments, radar systems, communication systems, and test equipment operating in this frequency range.

  20. V-band IMPATT transmitter

    NASA Technical Reports Server (NTRS)

    Williams, D.; Ying, R. S.

    1983-01-01

    A V-band transmitter for communication application was developed that has 30 dB gain and consists of six stages of IMPATT amplifiers. The low and medium power stages are stable amplifiers while the two high power stages are triggered oscillators. Hybrid couplers in the form of Magic Tees were used for power combining two single diode IMPATT modules in the high driver stage and for a single diode IMPATT modules at the output stage. Output power of 4 watts CW across a 2.5 GHz band centered at 60 GHz was achieved with an input power of 4 mW. Dynamic range of the amplifier chain is in excess of 7 dB. A single diode one watt stable amplifier over a bandwidth greater than 2.5 GHz, a high power ( 1 watt) stable amplifier capable of operating in either the constant current or constant voltage mode and verification of the advantages of the latter mode of operation; and a 10 channel modulator with built in test equipment (specifically protective circuitry, failure monitoring, and mode of failure indicated) were also developed. The performance requirements of circulators/isolators for reflection amplifiers were also defined and verified.

  1. LFI 30 and 44 GHz receivers Back-End Modules

    NASA Astrophysics Data System (ADS)

    Artal, E.; Aja, B.; de la Fuente, M. L.; Pascual, J. P.; Mediavilla, A.; Martinez-Gonzalez, E.; Pradell, L.; de Paco, P.; Bara, M.; Blanco, E.; García, E.; Davis, R.; Kettle, D.; Roddis, N.; Wilkinson, A.; Bersanelli, M.; Mennella, A.; Tomasi, M.; Butler, R. C.; Cuttaia, F.; Mandolesi, N.; Stringhetti, L.

    2009-12-01

    The 30 and 44 GHz Back End Modules (BEM) for the Planck Low Frequency Instrument are broadband receivers (20% relative bandwidth) working at room temperature. The signals coming from the Front End Module are amplified, band pass filtered and finally converted to DC by a detector diode. Each receiver has two identical branches following the differential scheme of the Planck radiometers. The BEM design is based on MMIC Low Noise Amplifiers using GaAs P-HEMT devices, microstrip filters and Schottky diode detectors. Their manufacturing development has included elegant breadboard prototypes and finally qualification and flight model units. Electrical, mechanical and environmental tests were carried out for the characterization and verification of the manufactured BEMs. A description of the 30 and 44 GHz Back End Modules of Planck-LFI radiometers is given, with details of the tests done to determine their electrical and environmental performances. The electrical performances of the 30 and 44 GHz Back End Modules: frequency response, effective bandwidth, equivalent noise temperature, 1/f noise and linearity are presented.

  2. 32-GHz cryogenically cooled HEMT low-noise amplifiers

    NASA Technical Reports Server (NTRS)

    Duh, K. H. George; Kopp, William F.; Ho, Pin; Chao, Pane-Chane; Ko, Ming-Yih; Smith, Phillip M.; Ballingall, James M.; Bautista, J. Javier; Ortiz, Gerardo G.

    1989-01-01

    The cryogenic noise temperature performance of a two-stage and a three-stage 32 GHz high electron mobility transistor (HEMT) amplifier was evaluated. The amplifiers employ 0.25 micrometer conventional AlGaAs/GaAs HEMT devices, hybrid matching input and output microstrip circuits, and a cryogenically stable dc biasing network. The noise temperature measurements were performed in the frequency range of 31 to 33 GHz over a physical temperature range of 300 K down to 12 K. Across the measurement band, the amplifiers displayed a broadband response, and the noise temperature was observed to decrease by a factor of 10 in cooling from 300 to 15 K. The lowest noise temperature measured for the two-stage amplifier at 32 GHz was 35 K with an associated gain of 16.5 dB, while the three-stage amplifier measured 39 K with an associated gain of 26 dB. It was further observed that both amplifiers were insensitive to light.

  3. On 32-GHz cryogenically cooled HEMT low-noise amplifiers

    NASA Technical Reports Server (NTRS)

    Bautista, J. J.; Ortiz, G. G.; Duh, K. H. G.; Kopp, W. F.; Ho, P.; Chao, P. C.; Kao, M. Y.; Smith, P. M.; Ballingall, J. M.

    1988-01-01

    The cryogenic noise temperature performance of a two-stage and a three-stage 32 GHz High Electron Mobility Transistor (HEMT) amplifier was evaluated. The amplifiers employ 0.25 micrometer conventional AlGaAs/GaAs HEMT devices, hybrid matching input and output microstrip circuits, and a cryogenically stable dc biasing network. The noise temperature measurements were performed in the frequency range of 31 to 33 GHz over a physical temperature range of 300 K down to 12 K. Across the measurement band, the amplifiers displayed a broadband response, and the noise temperature was observed to decrease by a factor of 10 in cooling from 300 K to 15 K. The lowest noise temperature measured for the two-stage amplifier at 32 GHz was 35 K with an associated gain of 16.5 dB, while the three-stage amplifier measured 39 K with an associated gain of 26 dB. It was further observed that both amplifiers were insensitive to light.

  4. The 20 GHz spacecraft IMPATT solid state transmitter

    NASA Technical Reports Server (NTRS)

    Best, T.; Ngan, Y. C.

    1986-01-01

    The engineering development of a solid-state transmitter amplifier operating in the 20-GHz frequency range is described. This effort involved a multitude of disciplines including IMPATT device development, circulator design, multiple-diode circuit design, and amplifier integration and test. The objective was to develop a transmitter amplifier demonstrating the feasibility of providing an efficient, reliable, lightweight solid-state transmitter to be flown on a 30 to 20 GHz communication demonstration satellite. The work was done under contract from NASA/Lewis Research Center for a period of three years. The result was the development of a GaAs IMPACT diode amplifier capable of an 11-W CW output power and a 2-dB bandwidth of 300 MHz. GaAs IMPATT diodes incorporating diamond heatsink and double-Read doping profile capable of 5.3-W CW oscillator output power and 15.5% efficiency were developed. Up to 19% efficiency was also observed for an output power level of 4.4 W. High performance circulators with a 0.2 dB inserting loss and bandwidth of 5 GHz have also been developed. These represent a significant advance in both device and power combiner circuit technologies in K-band frequencies.

  5. Demonstration of An Image Rejection Mixer for High Frequency Applications (26-36 GHz)

    NASA Technical Reports Server (NTRS)

    Bankston, Cheryl D.; Carlstrom, John E.

    1999-01-01

    A new high frequency image-rejection mixer was successfully tested in a 26-36 GHz band receiver. This paper briefly describes the motivation for implementation of an image rejection mixer in a receiver system, the basic operation of an image rejection mixer, and the development and testing of an image rejection mixer for a high frequency, cryogenic receiver system.

  6. 75 FR 71064 - Allocation and Designation of Spectrum for Fixed-Satellite Services in the 37.5-38.5 GHz, 40.5-41...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ... COMMISSION 47 CFR Part 25 Allocation and Designation of Spectrum for Fixed-Satellite Services in the 37.5-38... on technical rules for the Fixed-Satellite Service in the 37.5-42.5 GHz band. The purpose of this proceeding is to ensure that satellite operators in this band can share the band with terrestrial...

  7. A Cassegrain Offset-Fed Dual-Band Reflectarray

    NASA Technical Reports Server (NTRS)

    Huang, John; Han, Chulmin; Chang, Kai

    2006-01-01

    An X/Ka dual-band microstrip reflectarray with circular polarization (CP) has been constructed using thin membranes and Cassegrain offset-fed configuration. It is believed that this is the first Cassegrain reflectarray ever been developed. This antenna has a 75-cm-diameter aperture and uses metallic subreflector and angular-rotated annular ring elements. It achieved a measured -3dB-gain bandwidth of 700 MHz at X-band and 1.5 GHz at Ka-band, as well as a CP bandwidth (3dB axial ratio) of more than 700 MHz at X-band and more than 2 GHz at Ka-band. The measured peak efficiencies are 49.8% at X-band and 48.2% at Ka-band.

  8. Teleportation of a 3-dimensional GHZ State

    NASA Astrophysics Data System (ADS)

    Cao, Hai-Jing; Wang, Huai-Sheng; Li, Peng-Fei; Song, He-Shan

    2012-05-01

    The process of teleportation of a completely unknown 3-dimensional GHZ state is considered. Three maximally entangled 3-dimensional Bell states function as quantum channel in the scheme. This teleportation scheme can be directly generalized to teleport an unknown d-dimensional GHZ state.

  9. High power 303 GHz gyrotron for CTS in LHD

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Y.; Kasa, J.; Saito, T.; Tatematsu, Y.; Kotera, M.; Kubo, S.; Shimozuma, T.; Tanaka, K.; Nishiura, M.

    2015-10-01

    A high-power pulsed gyrotron is under development for 300 GHz-band collective Thomson scattering (CTS) diagnostics in the Large Helical Device (LHD). High-density plasmas in the LHD require a probe wave with power exceeding 100 kW in the sub-terahertz region to obtain sufficient signal intensity and large scattering angles. At the same time, the frequency bandwidth should be less than several tens of megahertz to protect the CTS receiver using a notch filter against stray radiations. Moreover, duty cycles of ~ 10% are desired for the time domain analysis of the CTS spectrum. At present, a 77 GHz gyrotron for electron cyclotron heating is used as a CTS wave source in the LHD. However, the use of such a low-frequency wave suffers from refraction, cutoff and absorption at the electron cyclotron resonance layer. Additionally, the signal detection is severely affected by background noise from electron cyclotron emission. To resolve those problems, high-power gyrotrons in the 300 GHz range have been developed. In this frequency range, avoiding mode competition is critical to realizing high-power and stable oscillation. A moderately over-moded cavity was investigated to isolate a desired mode from neighbouring modes. After successful tests with a prototype tube, the practical one was constructed with a cavity for TE22,2 operation mode, a triode electron gun forming intense laminar electron beams, and an internal mode convertor. We have experimentally confirmed single mode oscillation of the TE22,2 mode at the frequency of 303.3 GHz. The spectrum peak is sufficiently narrow. The output power of 290 kW has been obtained at the moment.

  10. 76 FR 56657 - Unlicensed Operation in the TV Broadcast Bands

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-14

    ... FR 75814, December 6, 2010, are effective on September 14, 2011. FOR FURTHER INFORMATION CONTACT: For... Devices Below 900 MHz and in the 3 GHz Band, ET Docket Nos. 04-186 and 02-380; FCC 10-174, 75 FR 75814... COMMISSION 47 CFR Parts 0 and 15 Unlicensed Operation in the TV Broadcast Bands AGENCY:...

  11. X-/Ka-band dichroic plate design and grating lobe study

    NASA Technical Reports Server (NTRS)

    Chen, J. C.

    1991-01-01

    An X-/Ka-band dichroic plate is needed for simultaneously receiving X-band and Ka-band in the DSS-13 Beam Waveguide Antenna. The plate is transparent to the allocated Ka-band downlink (31.8-32.3 GHz) and the frequency band for the Mars Observer Ka-band Beacon Link Experiment (KABLE) (33.6-33.8 GHz), while at the same time reflecting the X-band downlink (8.4-8.5 GHz). The design is made using a computer program for dichroic plates with rectangular holes. The theoretical performance of the X-/Ka-band dichroic plate is presented. A study of the grating lobe problem is also included in this article.

  12. Preliminary Results from NASA/GSFC Ka-Band High Rate Demonstration for Near-Earth Communications

    NASA Technical Reports Server (NTRS)

    Wong, Yen; Gioannini, Bryan; Bundick, Steven N.; Miller, David T.

    2004-01-01

    In early 2000, the National Aeronautics and Space Administration (NASA) commenced the Ka-Band Transition Project (KaTP) as another step towards satisfying wideband communication requirements of the space research and earth exploration-satellite services. The KaTP team upgraded the ground segment portion of NASA's Space Network (SN) in order to enable high data rate space science and earth science services communications. The SN ground segment is located at the White Sands Complex (WSC) in New Mexico. NASA conducted the SN ground segment upgrades in conjunction with space segment upgrades implemented via the Tracking and Data Relay Satellite (TDRS)-HIJ project. The three new geostationary data relay satellites developed under the TDRS-HIJ project support the use of the inter-satellite service (ISS) allocation in the 25.25-27.5 GHz band (the 26 GHz band) to receive high speed data from low earth-orbiting customer spacecraft. The TDRS H spacecraft (designated TDRS-8) is currently operational at a 171 degrees west longitude. TDRS I and J spacecraft on-orbit testing has been completed. These spacecraft support 650 MHz-wide Ka-band telemetry links that are referred to as return links. The 650 MHz-wide Ka-band telemetry links have the capability to support data rates up to at least 1.2 Gbps. Therefore, the TDRS-HIJ spacecraft will significantly enhance the existing data rate elements of the NASA Space Network that operate at S-band and Ku-band.

  13. Satellite-borne QPSK Direct Modulator for Ka Band

    NASA Astrophysics Data System (ADS)

    Zhang, Min; Li, Changsheng

    2016-02-01

    Ka band is referred to a microwave band whose frequency range is from 24.6 GHz to 40 GHz, it shares a wide available bandwidth, high frequency reuse rate and strong ability of anti-jamming. This paper presents a novel method to design a modulator for Ka-band satellite communication. Using QPSK to improve the ability of anti-jamming, using direct modulation to reduce the weight, volume and cost of electronic equipment, using sub-harmonic mixer to cut the LO power leakage, excellent modulation results are obtained.

  14. High power testing of a 17 GHz photocathode RF gun

    SciTech Connect

    Chen, S.C.; Danly, B.G.; Gonichon, J.

    1995-12-31

    The physics and technological issues involved in high gradient particle acceleration at high microwave (RF) frequencies are under study at MIT. The 17 GHz photocathode RF gun has a 1 1/2 cell ({pi} mode) room temperature cooper cavity. High power tests have been conducted at 5-10 MW levels with 100 ns pulses. A maximum surface electric field of 250 MV/m was achieved. This corresponds to an average on-axis gradient of 150 MeV/m. The gradient was also verified by a preliminary electron beam energy measurement. Even high gradients are expected in our next cavity design.

  15. A 30/20 GHz FSS feasibility study

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The near term feasibility of direct-to-subscriber services were determined using the 30/20 GHz Fixed Satellite Service (FSS) frequency bands. Those technologies which need to be further developed before such a system can be implemented, were identified. To determine this feasibility, dozens of potential applications were examined for their near-term viability, and the subscriber base of three promising applications were estimated. The system requirements, terminal design, and satellite architecture were all investigated to determine whether a 30/20 GHz FSS system is technically and economically feasible by mid-1990s. It was concluded that such a system is feasible, although maturation of some technologies is needed. This system would likely consist of one or two multibeam satellites serving hub/spoke networks of simple user terminals and more complex, mutli-channel terminals of the service providers. Rain compensation would be accomplished non-adaptively through the use of coding, nonuniform satellite TWT power that is a function of a beam's anticipated downlink fading, and signal regeneration of traffic to the wettest climate regions. It was estimated that a potential market of almost two million users could exist in in the mid-1990s time frame for home banking and financial services via Ka-band satellites.

  16. A compact 500GHz SIS receiver developed for space observations

    NASA Astrophysics Data System (ADS)

    Liu, D.; Yao, Q. J.; Li, J.; Shi, S. C.

    2011-08-01

    The submillimeter (submm) regime, ranging from 100 to 1000um, is an important frequency band for radio astronomy. A large number of astronomical spectral lines are located in this frequency region. Compared with ground-based observation, which is limited by the atmospheric absorption of signal, space borne platform provides perfect condition for submm observation. Here we introduce some preliminary results for a compact 500GHz SIS (Superconductor- Insulator-Superconductor) heterodyne receiver system developed for future space borne observation. Considering low power consumption requirement for space applications, we adopt a high critical temperature (Tc) NbN/AlN/NbN SIS tunnel junction for the mixer, a key component of the receiver system, which may work at relatively high temperature around 10 K. All the components, including the SIS mixer, HEMT low noise amplifier and optical lens, are assembled into a compact system. The whole system is cooled by a close-cycled 4K cryo-cooler in laboratory and test result shows a good noise performance, less than 250K at the 500GHz band. Detailed simulation and experimental results will be presented in this paper.

  17. The 18 and 30 GHz fixed service communications satellite system study. [to determine the cost and performance characteristics

    NASA Technical Reports Server (NTRS)

    Bronstein, L. M.

    1979-01-01

    The use of the 18 and 30 GHz bands for fixed service satellite communications is examined. The cost and performance expected of 18 and 30 GHz hardware is assessed, selected trunking and direct to user concepts are optimized, and the cost of these systems are estimated. The effect of rain attenuation on the technical and economic viability of the system and methods circumventing the problem are discussed. Technology developments are investigated and cost estimates of these developments are presented.

  18. Active wideband 350GHz imaging system for concealed-weapon detection

    NASA Astrophysics Data System (ADS)

    Sheen, David M.; Hall, Thomas E.; Severtsen, Ronald H.; McMakin, Douglas L.; Hatchell, Brian K.; Valdez, Patrick L. J.

    2009-05-01

    A prototype active wideband 350 GHz imaging system has been developed to address the urgent need for standoff concealed-weapon detection. This system is based on a wideband, heterodyne, frequency-multiplier-based transceiver system coupled to a quasi-optical focusing system and high-speed conical scanner. This system is able to quickly scan personnel for concealed weapons. Additionally, due to the wideband operation, this system provides accurate ranging information, and the images obtained are fully three-dimensional. Waves in the microwave, millimeter-wave, and terahertz (3 GHz to 1 THz) frequency bands are able to penetrate many optical obscurants, and can be used to form the basis of high-resolution imaging systems. Waves in the sub-millimeter-wave band (300 GHz to 1 THz) are particularly interesting for standoff concealed-weapon detection at ranges of 5 - 20+ meters, due to their unique combination of high resolution and clothing penetration. The Pacific Northwest National Laboratory (PNNL) has previously developed portal screening systems that operate at the lower end of the millimeter-wave frequency range around 30 GHz. These systems are well suited for screening within portals; however, increasing the range of these systems would dramatically reduce the resolution due to diffraction at their relatively long wavelength. In this paper, the standoff 350 GHz imaging system is described in detail and numerous imaging results are presented.

  19. Gastric Banding

    MedlinePlus

    ... gastric banding before deciding to have the procedure. Advertisements for a device or procedure may not include ... feeds Follow FDA on Twitter Follow FDA on Facebook View FDA videos on YouTube View FDA photos ...

  20. Performance of a first generation X-band photoelectron rf gun

    NASA Astrophysics Data System (ADS)

    Limborg-Deprey, C.; Adolphsen, C.; McCormick, D.; Dunning, M.; Jobe, K.; Li, H.; Raubenheimer, T.; Vrielink, A.; Vecchione, T.; Wang, F.; Weathersby, S.

    2016-05-01

    Building more compact accelerators to deliver high brightness electron beams for the generation of high flux, highly coherent radiation is a priority for the photon science community. A relatively straightforward reduction in footprint can be achieved by using high-gradient X-band (11.4 GHz) rf technology. To this end, an X-band injector consisting of a 5.5 cell rf gun and a 1-m long linac has been commissioned at SLAC. It delivers an 85 MeV electron beam with peak brightness somewhat better than that achieved in S-band photoinjectors, such as the one developed for the Linac Coherent Light Source (LCLS). The X-band rf gun operates with up to a 200 MV /m peak field on the cathode, and has been used to produce bunches of a few pC to 1.2 nC in charge. Notably, bunch lengths as short as 120 fs rms have been measured for charges of 5 pC (˜3 ×107 electrons), and normalized transverse emittances as small as 0.22 mm-mrad have been measured for this same charge level. Bunch lengths as short as 400 (250) fs rms have been achieved for electron bunches of 100 (20) pC with transverse normalized emittances of 0.7 (0.35) mm-mrad. We report on the performance and the lessons learned from the operation and optimization of this first generation X-band gun.

  1. A low noise 665 GHz SIS quasi-particle waveguide receiver

    NASA Technical Reports Server (NTRS)

    Kooi, J. W.; Walker, C. K.; Leduc, H. G.; Hunter, T. R.; Benford, D. J.; Phillips, T. G.

    1993-01-01

    Recent results on a 565-690 GHz SIS heterodyne receiver employing a 0.36 micron(sup 2) Nb/AlOx/Nb SIS tunnel junction with high quality circular non-contacting back short and E-plane tuners in a full height wave guide mount are reported. No resonant tuning structures were incorporated in the junction design at this time, even though such structures are expected to help the performance of the receiver. The receiver operates to at least the gap frequency of Niobium, approximately 680 GHz. Typical receiver noise temperatures from 565-690 GHz range from 160K to 230K with a best value of 185K DSB at 648 GHz. With the mixer cooled from 4.3K to 2K the measured receiver noise temperatures decreased by approximately 15 percent, giving roughly 180K DSB from 660 to 680 GHz. The receiver has a full 1 GHz IF pass band and was successfully installed at the Caltech Submillimeter Observatory in Hawaii.

  2. Relative performance of 8.5-GHz and 32-GHz telemetry links on the basis of total data return per pass

    NASA Astrophysics Data System (ADS)

    Koerner, M. A.

    1986-11-01

    The performance of X-band (8.5-GHz) and 32-GHz telemetry links is compared on the basis of the total data return per DSN station pass. Differences in spacecraft transmitter efficiency, transmit circuit loss, and transmitting antenna area efficiency and pointing loss are not considered in these calculations. Thus, the performance differentials calculated in this memo are those produced by a DSN 70-m station antenna gain and clear weather receiving system noise temperature and by weather. These calculations show that, assuming mechanical compensation of the DSN 70-m antenna for 32-GHz operation, a performance advantage for 32 GHz over X-band of 8.2 dB can be achieved for at least one DSN station location. Even if only Canberra and Madrid are used, a performance advantage of 7.7 dB can be obtained for at least one DSN station location. A system using a multiple beam feed (electronic compensation) should achieve similar results.

  3. An All-Solid-State, Room-Temperature, Heterodyne Receiver for Atmospheric Spectroscopy at 1.2 THz

    NASA Technical Reports Server (NTRS)

    Siles, Jose V.; Mehdi, Imran; Schlecht, Erich T.; Gulkis, Samuel; Chattopadhyay, Goutam; Lin, Robert H.; Lee, Choonsup; Gill, John J.; Thomas, Bertrand; Maestrini, Alain E.

    2013-01-01

    Heterodyne receivers at submillimeter wavelengths have played a major role in astrophysics as well as Earth and planetary remote sensing. All-solid-state heterodyne receivers using both MMIC (monolithic microwave integrated circuit) Schottky-diode-based LO (local oscillator) sources and mixers are uniquely suited for long-term planetary missions or Earth climate monitoring missions as they can operate for decades without the need for any active cryogenic cooling. However, the main concern in using Schottky-diode-based mixers at frequencies beyond 1 THz has been the lack of enough LO power to drive the devices because 1 to 3 mW are required to properly pump Schottky diode mixers. Recent progress in HEMT- (high-electron-mobility- transistor) based power amplifier technology, with output power levels in excess of 1 W recently demonstrated at W-band, as well as advances in MMIC Schottky diode circuit technology, have led to measured output powers up to 1.4 mW at 0.9 THz. Here the first room-temperature tunable, all-planar, Schottky-diode-based receiver is reported that is operating at 1.2 THz over a wide (˜20%) bandwidth. The receiver front-end (see figure) consists of a Schottky-diode-based 540 to 640 GHz multiplied LO chain (featuring a cascade of W-band power amplifiers providing around 120 to 180 mW at W-band), a 200-GHz MMIC frequency doubler, and a 600-GHz MMIC frequency tripler, plus a biasable 1.2-THz MMIC sub-harmonic Schottky-diode mixer. The LO chain has been designed, fabricated, and tested at JPL and provides around 1 to 1.5 mW at 540 o 640 GHz. The sub-harmonic mixer consists of two Schottky diodes on a thin GaAs membrane in an anti-parallel configuration. An integrated metal insulator metal (MIM) capacitor has been included on-chip to allow dc bias for the Schottky diodes. A bias voltage of around 0.5 V/diode is necessary to reduce the LO power required down to the 1 to 1.5 mW available from the LO chain. The epilayer thickness and doping profiles have

  4. Performance of the X-/Ka/KABLE-band dichroic plate in the DSS-13 beam waveguide antenna

    NASA Technical Reports Server (NTRS)

    Chen, J. C.; Stanton, P. H.; Reilly, H. F.

    1993-01-01

    The first Ka-band downlink demonstration was recently carried out by the Ka-Band Link Experiment (KABLE) in association with the Mars Observer spacecraft. In order to support the mission, a dichroic plate was required in the DSS-13 beam waveguide antenna to allow simultaneous X- and Ka-band operation. An X-/ Ka-/ KABLE-band dichroic plate was designed to transmit Ka-band downlink (31.8-32.3 GHz), Ka-band uplink (34.2-34.7 GHz), and KABLE (33.6-33.8 GHz) frequencies, while reflecting X-band (8.4-8.5 GHz). A computer program was developed for the analysis of a dichroic plate with rectangular apertures by using the mode-matching method. The plate was then fabricated and tested. The reflection, group delay, and noise temperature in the antenna system due to the dichroic plate were measured. The experimental results show good agreement with theoretical prediction.

  5. Concepts for 18/30 GHz satellite communication system study. Executive summary

    NASA Technical Reports Server (NTRS)

    Baker, M.; Davies, R.; Cuccia, L.; Mitchell, C.

    1979-01-01

    An examination of a multiplicity of interconnected parameters ranging from specific technology details to total system economic costs for satellite communication systems at the 18/30 GHz transmission bands are presented. It was determined that K sub A band systems can incur a small communications outage during very heavy rainfall periods and that reducing the outage to zero would lead to prohibitive system costs. On the other hand, the economics of scale, ie, one spacecraft accommodating 2.5 GHz of bandwidth coupled with multiple beam frequency reuse, leads to very low costs for those users who can tolerate the 5 to 50 hours per year of downtime. A multiple frequency band satellite network can provide the ultimate optimized match to the consumer performance/economics demands.

  6. 60 GHz low noise wideband receiver

    NASA Technical Reports Server (NTRS)

    Knust-Graichen, R. A.; Bui, L.

    1985-01-01

    The printed circuit and GaAs beam lead technology-based, low noise integrated receiver presented was developed for low cost space communications and operates in the 59-64 GHz range, using a phase-locked Gunn oscillator at 51.5 GHz. An IF output of 7.5-12.5 GHz is obtained. With the exception of the IF amplifier, and of the E-plane technology-based RF preselect filter, all circuits of the device employ suspended stripline construction.

  7. TWT design requirements for 30/20 GHz digital communications' satellite

    NASA Technical Reports Server (NTRS)

    Stankiewicz, N.; Anzic, G.

    1979-01-01

    The rapid growth of communication traffic (voice, data, and video) requires the development of additional frequency bands before the 1990's. The frequencies currently in use for satellite communications at 6/4 GHz are crowded and demands for 14/12 GHz systems are increasing. Projections are that these bands will be filled to capacity by the late 1980's. The next higher frequency band allocated for satellite communications is at 30/20 GHz. For interrelated reasons of efficiency, power level, and system reliability criteria, a candidate for the downlink amplifier in a 30/20 GHz communications' satellite is a dual mode traveling wave tube (TWT) equipped with a highly efficient depressed collector. A summary is given of the analyses which determine the TWT design requirements. The overall efficiency of such a tube is then inferred from a parametric study and from experimental data on multistaged depressed collectors. The expected TWT efficiency at 4 dB below output saturation is 24 percent in the high mode and 22 percent in the low mode.

  8. Tri-band small monopole antenna based on SRR units

    NASA Astrophysics Data System (ADS)

    Shehata, Gehan; Mohanna, Mahmoud; Rabeh, Mohammed Lotfy

    2015-12-01

    In this paper a novel design for a tri-band monopole antenna coupled with metamaterial units is introduced. The proposed antenna was designed to cover WiMAX (2.5, 3.5) and WLAN (5.2) bands. In our proposal, a coplanar waveguide (CPW) fed circular-disk monopole antenna is coupled with three split ring resonator (SRR) units which exist on its back side. In our design a monopole antenna and SRR units are designed first to resonate at 5.2 GHz and 2.5 GHz respectively. In addition, antenna is loaded with post to force resonance at 3.5 GHz. SRR units are used for 2.5 GHz resonance to miniaturize antenna size, and our proposed antenna considered an electrically small antenna (ESA) at its first resonance frequency. Simulated and measured results exhibit a good agreement that validate our design.

  9. Dual-band bandpass filter using composite metamaterial resonator

    NASA Astrophysics Data System (ADS)

    Jin, Yu-Ting; Si, Li-Ming; Zhang, Qing-Le; Wu, Yu-Ming; Lv, Xin

    2016-03-01

    A dual-band bandpass filter at X-band is proposed using composite metamaterial resonator consisting of an outer square closed-ring resonator (SCRR) and two inner electric inductance-capacitance (ELC) resonators. Numerical simulation and microwave measurement reveal that the filter exhibits two passbands centered at 8.76 GHz and 11.04 GHz, with 3 dB bandwidths of 130 MHz and 290 MHz, respectively. The complex dispersion relation of the filter is further derived based on the effective medium theory, where two balanced composite right-/left-handed bands are found, i.e. lines exhibiting two left-handed and two right-handed bands alternating. The proposed filter may find useful in dual-band or multi-band wireless communication systems.

  10. High Power Local Oscillator Sources for 1-2 THz

    NASA Technical Reports Server (NTRS)

    Mehdi, Imran; Thomas, Bertrand; Lin, Robert; Maestrini, Alain; Ward, John; Schlecht, Erich; Gill, John; Lee, Choonsup; Chattopadhyay, Goutam; Maiwald, Frank

    2010-01-01

    Recent results from the Heterodyne Instrument for Far-Infrared (HIFI) on the Herschel Space Telescope have confirmed the usefulness of high resolution spectroscopic data for a better understanding of our Universe. This paper will explore the current status of tunable local oscillator sources beyond HIFI and provide demonstration of how power combining of GaAs Schottky diodes can be used to increase both power and upper operating frequency for heterodyne receivers. Availability of power levels greater than 1 watt in the W-band now makes it possible to design a 1900 GHz source with more than 100 microwatts of expected output power.

  11. An 8.4-GHz cryogenically cooled HEMT amplifier for DSS 13

    NASA Technical Reports Server (NTRS)

    Tanida, L.

    1988-01-01

    A prototype 8.4 GHz (X-band) high electron mobility transistor (HEMT) amplifier/closed cycle refrigerator system was installed in the Deep Space Station 13 feedcone in August 1987. The amplifier is cryogenically cooled to a physical temperature of 12 K and provides 31 K antenna noise temperature (zenith) and 35 dB of gain at a frequency of 8.2 to 8.6 GHz. Antenna system noise temperature is less than 50 K from 7.2 to 9.4 MHz. The low noise HEMT amplifier system is intended for use as a radio astronomy or space communications receiver front end.

  12. The Arcetri 40-50 GHz receiver for the Medicina Radiotelescope.

    NASA Astrophysics Data System (ADS)

    Tofani, G.; Catarzi, M.; Natale, V.

    Numerous spectral lines of relevant astronomical importance are available in the wavelength range between 20 and 70 GHz. In this band transitions of several molecules like SiO, CS, HNCO, CH3OH, H2CO plays a central role in the different phases of the interstellar medium. In order to extend the observations with the Medicina Radiotelescope of Galactic masers, a cooled receiver operating in the range 40-50 GHz has been built for continuum and line observations. The system has been tested at the Cassegrain focus of the Medicina Radiotelescope on continuum and SiO maser sources.

  13. AMI 15 GHz upper limits for the nearby Type Ia supernova SN 2016coj

    NASA Astrophysics Data System (ADS)

    Mooley, K. P.; Fender, R. P.; Cantwell, T.; Titterington, D.; Saunders, R.; Carey, S.; Hickish, J.; Perrott, Y. C.; Razavi-Ghods, N.; Scott, P.; Grainge, K.; Scaife, A.

    2016-06-01

    We observed the type Ia supernova SN 2016coj in NGC 4125 (Zheng et al., ATel #9095; d=19Mpc; discovery date 2016 May 28.18) with the AMI Large Array at 15 GHz. We detected a fading source (later found to be a chance coincidence; see below) at the location of the supernova on 2016 Jun 03.86, Jun 05.89 and Jun 09.76 UT, following which we triggered the Jansky VLA. The VLA observations, carried out between 2-18 GHz on Jun 11.07 UT, gave 3sigma upper limits of ~60 uJy at S, C, X and Ku bands.

  14. A low-cost multiple-channel 12-GHz receiver for satellite television broadcasting

    NASA Technical Reports Server (NTRS)

    Risch, C. O.; Singh, J. P.; Rosenbaum, F. J.; Gregory, R. O.

    1975-01-01

    The design of a low-cost FM-microwave satellite-ground-station receiver is described. It is capable of accepting 12 contiguous color-television equivalent-bandwidth channels in the 11.72-12.2-GHz band using a wide-band FM format and frequency division multiplexing (FDM) of the channels. Each channel has 36 MHz of usable bandwidth with a 4-MHz guard band and provides a CATV compatible output. The overall system specifications are first discussed. Then consideration is given to the design, fabrication, and evaluation of the different subsystems in the receiver.

  15. The 64 meter antenna operation at K sub A band

    NASA Technical Reports Server (NTRS)

    Potter, P. D.

    1980-01-01

    The future potential of the 32 GHz K sub A band frequency region to planetary exploration, and the expected performance of the 64 m antenna network at 32 GHz is addressed. A modest level of noninterference upgrade work is assumed to achieve reasonable antenna aperture efficiency and alleviate antenna pointing difficulties. Electronic compensation of antenna aperture phasing errors is briefly considered as an alternative to the physical upgrade.

  16. Analysis of Resonance Response Performance of C-Band Antenna Using Parasitic Element

    PubMed Central

    Islam, M. T.; Misran, N.; Mandeep, J. S.

    2014-01-01

    Analysis of the resonance response improvement of a planar C-band (4–8 GHz) antenna is proposed using parasitic element method. This parasitic element based method is validated for change in the active and parasitic antenna elements. A novel dual-band antenna for C-band application covering 5.7 GHz and 7.6 GHz is designed and fabricated. The antenna is composed of circular parasitic element with unequal microstrip lines at both sides and a rectangular partial ground plane. A fractional bandwidth of 13.5% has been achieved from 5.5 GHz to 6.3 GHz (WLAN band) for the lower band. The upper band covers from 7.1 GHz to 8 GHz with a fractional bandwidth of 12%. A gain of 6.4 dBi is achieved at the lower frequency and 4 dBi is achieved at the upper frequency. The VSWR of the antenna is less than 2 at the resonance frequency. PMID:24895643

  17. Analysis of resonance response performance of C-band antenna using parasitic element.

    PubMed

    Zaman, M R; Islam, M T; Misran, N; Mandeep, J S

    2014-01-01

    Analysis of the resonance response improvement of a planar C-band (4-8 GHz) antenna is proposed using parasitic element method. This parasitic element based method is validated for change in the active and parasitic antenna elements. A novel dual-band antenna for C-band application covering 5.7 GHz and 7.6 GHz is designed and fabricated. The antenna is composed of circular parasitic element with unequal microstrip lines at both sides and a rectangular partial ground plane. A fractional bandwidth of 13.5% has been achieved from 5.5 GHz to 6.3 GHz (WLAN band) for the lower band. The upper band covers from 7.1 GHz to 8 GHz with a fractional bandwidth of 12%. A gain of 6.4 dBi is achieved at the lower frequency and 4 dBi is achieved at the upper frequency. The VSWR of the antenna is less than 2 at the resonance frequency. PMID:24895643

  18. The Q/U Imaging Experiment: Polarization Measurements of Radio Sources at 43 and 95 GHz

    NASA Astrophysics Data System (ADS)

    Huffenberger, K. M.; Araujo, D.; Bischoff, C.; Buder, I.; Chinone, Y.; Cleary, K.; Kusaka, A.; Monsalve, R.; Næss, S. K.; Newburgh, L. B.; Reeves, R.; Ruud, T. M.; Wehus, I. K.; Zwart, J. T. L.; Dickinson, C.; Eriksen, H. K.; Gaier, T.; Gundersen, J. O.; Hasegawa, M.; Hazumi, M.; Miller, A. D.; Radford, S. J. E.; Readhead, A. C. S.; Staggs, S. T.; Tajima, O.; Thompson, K. L.; QUIET Collaboration

    2015-06-01

    We present polarization measurements of extragalactic radio sources observed during the cosmic microwave background polarization survey of the Q/U Imaging Experiment (QUIET), operating at 43 GHz (Q-band) and 95 GHz (W-band). We examine sources selected at 20 GHz from the public, >40 mJy catalog of the Australia Telescope (AT20G) survey. There are ˜480 such sources within QUIET’s four low-foreground survey patches, including the nearby radio galaxies Centaurus A and Pictor A. The median error on our polarized flux density measurements is 30-40 mJy per Stokes parameter. At signal-to-noise ratio > 3 significance, we detect linear polarization for seven sources in Q-band and six in W-band; only 1.3 ± 1.1 detections per frequency band are expected by chance. For sources without a detection of polarized emission, we find that half of the sources have polarization amplitudes below 90 mJy (Q-band) and 106 mJy (W-band), at 95% confidence. Finally, we compare our polarization measurements to intensity and polarization measurements of the same sources from the literature. For the four sources with WMAP and Planck intensity measurements >1 Jy, the polarization fractions are above 1% in both QUIET bands. At high significance, we compute polarization fractions as much as 10%-20% for some sources, but the effects of source variability may cut that level in half for contemporaneous comparisons. Our results indicate that simple models—ones that scale a fixed polarization fraction with frequency—are inadequate to model the behavior of these sources and their contributions to polarization maps.

  19. Beam Dynamics Study of X-Band Linac Driven X-Ray FELS

    SciTech Connect

    Adolphsen, C.; Limborg-Deprey, C.; Raubenheimer, T.O.; Wu, J.; Sun, Y.; /SLAC

    2011-12-13

    Several linac driven X-ray Free Electron Lasers (XFELs) are being developed to provide high brightness photon beams with very short, tunable wavelengths. In this paper, three XFEL configurations are proposed that achieve LCLS-like performance using X-band linac drivers. These linacs are more versatile, efficient and compact than ones using S-band or C-band rf technology. For each of the designs, the overall accelerator layout and the shaping of the bunch longitudinal phase space are described briefly. During the last 40 years, the photon wavelengths from linac driven FELs have been pushed shorter by increasing the electron beam energy and adopting shorter period undulators. Recently, the wavelengths have reached the X-ray range, with FLASH (Free-Electron Laser in Hamburg) and LCLS (Linac Coherent Light Source) successfully providing users with soft and hard X-rays, respectively. FLASH uses a 1.2 GeV L-band (1.3 GHz) superconducting linac driver and can deliver 10-70 fs FWHM long photon pulses in a wavelength range of 44 nm to 4.1 nm. LCLS uses the last third of the SLAC 3 km S-band (2.856 GHz) normal-conducting linac to produce 3.5 GeV to 15 GeV bunches to generate soft and hard X-rays with good spatial coherence at wavelengths from 2.2 nm to 0.12 nm. Newer XFELs (at Spring8 and PSI) use C-band (5.7 GHz) normal-conducting linac drivers, which can sustain higher acceleration gradients, and hence shorten the linac length, and are more efficient at converting rf energy to bunch energy. The X-band (11.4 GHz) rf technology developed for NLC/GLC offers even higher gradients and efficiencies, and the shorter rf wavelength allows more versatility in longitudinal bunch phase space compression and manipulation. In the following sections, three different configurations of X-band linac driven XFELs are described that operate from 6 to 14 GeV. The first (LOW CHARGE DESIGN) has an electron bunch charge of only 10 pC; the second (OPTICS LINEARIZATION DESIGN) is based on optics

  20. Low-noise hybrid superconductor/semiconductor 7.4 GHz receiver downconverter for NASA space applications

    SciTech Connect

    Javadi, H.H.S.; Barner, J.B.; Bautista, J.J.

    1994-12-31

    A low-noise microwave receiver downconverter utilizing thin-film high-critical-temperature superconducting (HTS) passive circuitry and semiconductor active devices has been developed for use in space. It consists of an HTS preselect filter, a cryogenic low-noise amplifier, a cryogenic mixer, and a cryogenic oscillator with an HTS resonator. The downconverter converts a 200 MHz wide band centered around 7.35 GHz to a band centered around 1.0 GHz. When cooled to 77 K, the downconverter plus cables inside a cryogenic refrigerator produced a noise temperature measured at the refrigerator port of approximately 50 K with conversion gain of 18 dB.

  1. Recent operating experience with Varian 70 GHz and 140 GHz gyrotrons

    SciTech Connect

    Felch, K.; Bier, R.; Fox, L.; Huey, H.; Ives, L.; Jory, H.; Lopez, N.; Shively, J.; Spang, S.

    1985-01-01

    The design features and initial test results of Varian 70 GHz and 140 GHz CW gyrotrons are presented. The first experimental 140 GHz tube has achieved an output power of 102 kW at 24% efficiency under pulsed conditions in the desired TE031 cavity mode. Further tests aimed at achieving the design goal of 100 kW CW are currently underway. The 70 GHz tube has achieved an output power of 200 kW under pulsed conditions and possesses a wide dynamic range for output power variations. 6 refs., 8 figs.

  2. Band Together!

    ERIC Educational Resources Information Center

    Olson, Cathy Applefeld

    2011-01-01

    After nearly a decade as band director at St. James High School in St. James, Missouri, Derek Limback knows that the key to building a successful program is putting the program itself above everything else. Limback strives to augment not only his students' musical prowess, but also their leadership skills. Key to his philosophy is instilling a…

  3. Ka-band study: 1988

    NASA Technical Reports Server (NTRS)

    Layland, J. W.; Horttor, R. L.; Clauss, R. C.; Wilcher, J. H.; Wallace, R. J.; Mudgway, D. J.

    1989-01-01

    The Ka-band study team was chartered in late 1987 to bring together all the planning elements for establishing 32 GHz (Ka-band) as the primary downlink frequency for deep-space operation, and to provide a stable baseline from which to pursue that development. This article summarizes the results of that study at its conclusion in mid-1988, and corresponds to material presented to NASA's Office of Space Operations on July 14, 1988. For a variety of reasons, Ka-band is the right next major step in deep-space communications. It offers improved radio metric accuracy through reduced plasma sensitivity and increased bandwidth. Because of these improvements, it offers the opportunity to reduce costs in the flight radio system or in the DSN by allocating part of the overall benefits of Ka-band to this cost reduction. A mission scenario is being planned that can drive at least two and possibly all three of the DSN subnets to provide a Ka-band downlink capability by the turn of the century. The implementation scenario devised by the study team is believed to be feasible within reasonable resource expectations, and capable of providing the needed upgrade as a natural follow-on to the technology development which is already underway.

  4. High precision 6.8GHz phase locking of coherent laser beams for optical lattice experiment

    NASA Astrophysics Data System (ADS)

    Ding, Xun; Sang, Linlin; Zhang, Chen; Jin, Ge; Jiang, Xiao

    2013-12-01

    With the optical phase lock loop (OPLL) we made, we can achieve phase locking at frequency differences ranging from 0.5GHz to 7.5 GHz. This OPLL is fully applicable in atomic physics experiments, mostly in coherent lasers frequency locking. Two kinds of modulation modes were brought to ensure the frequency range and precision: the fast feedback current as the injection current and the slow feedback current to adjust the piezo-electric transducer. This device has been put into an optical lattice platform to lock a laser used for cooling and trapping atoms. The beat signal has a -3dB band width of 1Hz at 6.834GHz, corresponding to the hyperfine splitting of the ground state 87Rb atom.

  5. High-power 140-GHz quasioptical gyrotron traveling-wave amplifier.

    PubMed

    Sirigiri, J R; Shapiro, M A; Temkin, R J

    2003-06-27

    We present the design and experimental results of a novel quasioptical gyrotron traveling-wave tube (gyro-TWT) amplifier at 140 GHz. The gyro-TWT produced up to 30 kW of peak power in 2 micros pulsed operation at 6 Hz achieving a peak gain of 29 dB, a peak efficiency of 12%, and a bandwidth of 2.3 GHz. The device was operated in a very higher-order mode of an open quasioptical interaction structure, namely, a confocal waveguide. The diffraction loss from the open sidewalls of the confocal waveguide was used to suppress mode competition in this highly overmoded circuit resulting in a stable single-mode operation. The experiment achieved record high power levels at 140 GHz for a gyro-TWT. These experiments demonstrate the effectiveness of using overmoded quasioptical waveguide interaction structures for generating high power in the millimeter and submillimeter wave bands with a gyro-TWT. PMID:12857176

  6. A 330-500 GHz Zero-Biased Broadband Tripler Based on Terahertz Monolithic Integrated Circuits

    NASA Astrophysics Data System (ADS)

    Ren, Tian-Hao; Zhang, Yong; Yan, Bo; Xu, Rui-Min; Yang, Cheng-Yue; Zhou, Jing-Tao; Jin, Zhi

    2015-02-01

    A 330-500 GHz zero-biased broadband monolithic integrated tripler is reported. The measured results show that the maximum efficiency and the maximum output power are 2% and 194 μW at 348 GHz. The saturation characteristic test shows that the output 1 dB compression point is about -8.5 dBm at 334 GHz and the maximum efficiency is obtained at the point, which is slightly below the 1 dB compression point. Compared with the conventional hybrid integrated circuit, a major advantage of the monolithic integrated circuit is the significant improvement of reliability and consistency. In this work, a terahertz monolithic frequency multiplier at this band is designed and fabricated.

  7. Hybrid Band effects program (Lockheed Martin shared vision CRADA)

    SciTech Connect

    Bacon, L. D.

    2012-03-01

    Hybrid Band{trademark} (H-band) is a Lockheed Martin Missiles and Fire Control (LMMFC) designation for a specific RF modulation that causes disruption of select electronic components and circuits. H-Band enables conventional high-power microwave (HPM) effects (with a center frequency of 1 to 2 GHz, for example) using a higher frequency carrier signal. The primary technical objective of this project was to understand the fundamental physics of Hybrid Band{trademark} Radio Frequency effects on electronic systems. The follow-on objective was to develop and validate a Hybrid Band{trademark} effects analysis process.

  8. Photonic-Band-Gap Traveling-Wave Gyrotron Amplifier

    PubMed Central

    Nanni, E. A.; Lewis, S. M.; Shapiro, M. A.; Griffin, R. G.; Temkin, R. J.

    2014-01-01

    We report the experimental demonstration of a gyrotron traveling-wave-tube amplifier at 250 GHz that uses a photonic band gap (PBG) interaction circuit. The gyrotron amplifier achieved a peak small signal gain of 38 dB and 45 W output power at 247.7 GHz with an instantaneous −3 dB bandwidth of 0.4 GHz. The amplifier can be tuned for operation from 245–256 GHz. The widest instantaneous −3 dB bandwidth of 4.5 GHz centered at 253.25 GHz was observed with a gain of 24 dB. The PBG circuit provides stability from oscillations by supporting the propagation of transverse electric (TE) modes in a narrow range of frequencies, allowing for the confinement of the operating TE03-like mode while rejecting the excitation of oscillations at nearby frequencies. This experiment achieved the highest frequency of operation for a gyrotron amplifier; at present, there are no other amplifiers in this frequency range that are capable of producing either high gain or high output power. This result represents the highest gain observed above 94 GHz and the highest output power achieved above 140 GHz by any conventional-voltage vacuum electron device based amplifier. PMID:24476286

  9. Photonic-band-gap traveling-wave gyrotron amplifier.

    PubMed

    Nanni, E A; Lewis, S M; Shapiro, M A; Griffin, R G; Temkin, R J

    2013-12-01

    We report the experimental demonstration of a gyrotron traveling-wave-tube amplifier at 250 GHz that uses a photonic band gap (PBG) interaction circuit. The gyrotron amplifier achieved a peak small signal gain of 38 dB and 45 W output power at 247.7 GHz with an instantaneous -3  dB bandwidth of 0.4 GHz. The amplifier can be tuned for operation from 245-256 GHz. The widest instantaneous -3  dB bandwidth of 4.5 GHz centered at 253.25 GHz was observed with a gain of 24 dB. The PBG circuit provides stability from oscillations by supporting the propagation of transverse electric (TE) modes in a narrow range of frequencies, allowing for the confinement of the operating TE03-like mode while rejecting the excitation of oscillations at nearby frequencies. This experiment achieved the highest frequency of operation for a gyrotron amplifier; at present, there are no other amplifiers in this frequency range that are capable of producing either high gain or high output power. This result represents the highest gain observed above 94 GHz and the highest output power achieved above 140 GHz by any conventional-voltage vacuum electron device based amplifier. PMID:24476286

  10. W/V-Band RF Propagation Experiment Design

    NASA Technical Reports Server (NTRS)

    Acosta, Roberto J.; Nessel, James A.; Simons, Rainee N.; Zemba, Michael J.; Morse, Jacquelynne Rose; Budinger, James M.

    2012-01-01

    The utilization of frequency spectrum for space-to-ground communications applications has generally progressed from the lowest available bands capable of supporting transmission through the atmosphere to the higher bands, which have required research and technological advancement to implement. As communications needs increase and the available spectrum in the microwave frequency bands (3 30 GHz) becomes congested globally, future systems will move into the millimeter wave (mm-wave) range (30 300 GHz). While current systems are operating in the Ka-band (20 30 GHz), systems planned for the coming decades will initiate operations in the Q-Band (33 50 GHz), V-Band (50 75 GHz) and W Band (75 110 GHz) of the spectrum. These bands offer extremely broadband capabilities (contiguous allocations of 500 MHz to 1GHz or more) and an uncluttered spectrum for a wide range of applications. NASA, DoD and commercial missions that can benefit from moving into the mm-wave bands include data relay and near-Earth data communications, unmanned aircraft communications, NASA science missions, and commercial broadcast/internet services, all able to be implemented via very small terminals. NASA Glenn Research Center has a long history of performing the inherently governmental function of opening new frequency spectrum by characterizing atmospheric effects on electromagnetic propagation and collaborating with the satellite communication industry to develop specific communications technologies for use by NASA and the nation. Along these lines, there are critical issues related to W/V-band propagation that need to be thoroughly understood before design of any operational system can commence. These issues arise primarily due to the limitations imposed on W/V-band signal propagation by the Earth s atmosphere, and to the fundamental lack of understanding of these effects with regards to proper system design and fade mitigation. In this paper, The GRC RF propagation team recommends measurements

  11. X-band uplink feedcone capabilities, components, and layout

    NASA Astrophysics Data System (ADS)

    Marlin, H.; Freiley, A.; Hartop, R.

    1986-11-01

    Two new X-(7.2 GHz up, 8.4 GHz down) and S-band (2.1 to 2.3 Ghz) common aperture (XSC) feedcones are being added to the DSS 45 and DSS 65 34-Meter Efficiency Antennas. These new feedcones are modifications of the existing SXC feedcone design incorporating a new high power (20-kW) X-band transmitter. The modified Antenna Microwave Subsystem design also incorporates two additional X-band low noise amplifiers and greater phase stability performance to meet both the increased stability requirements for Galileo gravity wave experiments and requirements for spacecraft navigation near the Sun. A third XSC will be constructed for DSS 15 later.

  12. Tri-band microstrip antenna design for wireless communication applications

    NASA Astrophysics Data System (ADS)

    Sami, Gehan; Mohanna, Mahmoud; Rabeh, Mohamed L.

    2013-06-01

    This paper introduces a novel rectangular tri-band patch antenna that is fabricated and measured for wireless communication systems. The introduced antenna is designed for WLAN and WiMAX applications. The desired tri-band operation was obtained by proper loading for a rectangular patch antenna using slots and shorting pins. The optimal location and dimension for the loaded elements were obtained with the aid of interfacing a Genetic Algorithm (GA) model with an Ansoft High Frequency Structural Simulator (HFSS). The results obtained from our simulated antenna show 5.8% impedance matching band width at 2.4 GHz, 3.7% at 3.5 GHz and 1.57% at 5.7 GHz. In addition, an equivalent circuit of the proposed antenna is introduced using the least square curve fitting optimization technique.

  13. Low-Noise MMIC Amplifiers for 120 to 180 GHz

    NASA Technical Reports Server (NTRS)

    Pukala, David; Samoska, Lorene; Peralta, Alejandro; Bayuk, Brian; Grundbacher, Ron; Oliver, Patricia; Cavus, Abdullah; Liu, Po-Hsin

    2009-01-01

    Three-stage monolithic millimeter-wave integrated-circuit (MMIC) amplifiers capable of providing useful amounts of gain over the frequency range from 120 to 180 GHz have been developed as prototype low-noise amplifiers (LNAs) to be incorporated into instruments for sensing cosmic microwave background radiation. There are also potential uses for such LNAs in electronic test equipment, passive millimeter- wave imaging systems, radar receivers, communication receivers, and systems for detecting hidden weapons. The main advantage afforded by these MMIC LNAs, relative to prior MMIC LNAs, is that their coverage of the 120-to-180-GHz frequency band makes them suitable for reuse in a wider variety of applications without need to redesign them. Each of these MMIC amplifiers includes InP transistors and coplanar waveguide circuitry on a 50- mthick chip (see Figure 1). Coplanar waveguide transmission lines are used for both applying DC bias and matching of input and output impedances of each transistor stage. Via holes are incorporated between top and bottom ground planes to suppress propagation of electromagnetic modes in the substrate. On the basis of computational simulations, each of these amplifiers was expected to operate with a small-signal gain of 14 dB and a noise figure of 4.3 dB. At the time of writing this article, measurements of noise figures had not been reported, but on-chip measurements had shown gains approaching their simulated values (see Figure 2).

  14. Design of a Ka-band gyro-TWT amplifier for broadband operation

    SciTech Connect

    Alaria, Mukesh Kumar; Sinha, A. K.; Choyal, Y.

    2013-07-15

    In this paper, the design of a Ka-band periodically ceramic loaded gyro-TWT amplifier has been carried out. The design predict that the interaction structure can produce more than 80 kW output power, 50 dB saturated gain, and 3 dB bandwidth for 65 kV and 5 A electron beam with velocity ratio (α) of 1.2. This paper describes the design and simulation of a high performance 35 GHz TE{sub 01} mode gyro-TWT that applies the same technique of employing a periodic dielectric loaded interaction structure to achieve stability and wide bandwidth. The design of input coupler with loaded interaction structure for Ka-band Gyro-TWT has been carried out using Ansoft hfss. The return loss (S{sub 11}) and transmission loss (S{sub 21}) of the Ka-band gyro-TWT input coupler have been found to be −27.3 dB and −0.05 dB, respectively. The design of output window for Ka-band Gyro-TWT has been carried out using cst microwave studio.

  15. W-band accelerator study in KEK

    NASA Astrophysics Data System (ADS)

    Zhu, Xiongwei; Nakajima, Kazuhisa

    2001-05-01

    In this paper, we summarize the W-band accelerator study in KEK. We present a design study on W-Band photocathode RF gun which is capable of generating and accelerating 300 pC electron bunch. The design system is made up of 91.392 GHz photocathode RF gun and 91.392 GHz traveling wave linac cells. Based on the numerical simulation using SUPERFISH and PARMELA and the conventional RF linac scaling law, the design will produce 300 pC at 1.74 MeV with bunch length 0.72 ps and normalized transverse emittance 0.55 mm mrad. We study the beam dynamics in high frequency and high gradient; due to the high gradient, the pondermotive effect plays an important role in beam dynamics; we found the pondermotive effect still exist with only the fundamental space harmonics (synchrotron mode) due to the coupling of the transverse and longitudinal motion.

  16. Feasibility study of a Ka-/Ka-band dichroic plate with stepped rectangular apertures

    NASA Technical Reports Server (NTRS)

    Chen, J. C.

    1993-01-01

    For the Cassini spacecraft mission, a dichroic plate is needed to pass Ka-band uplink (34.2 to 34.7 GHz) and to reflect Ka-band downlink (31.8 to 32.3 GHz) for dual-frequency operation in the Deep Space Network. The special characteristic of the Ka-/Ka-band dichroic plate is that the pass band and the reflective band are only 1.9 GHz (5.7 percent) apart. A thick dichroic plate with stepped rectangular apertures that function as resonator filters was chosen for the Ka-/Ka-band dichroic plate design. The results of the feasibility study are presented in this article.

  17. EPR of Cu2+ Prion Protein Constructs at 2 GHz Using the g⊥ Region to Characterize Nitrogen Ligation

    PubMed Central

    Hyde, James S.; Bennett, Brian; Walter, Eric D.; Millhauser, Glenn L.; Sidabras, Jason W.; Antholine, William E.

    2009-01-01

    Abstract A double octarepeat prion protein construct, which has two histidines, mixed with copper sulfate in a 3:2 molar ratio provides at most three imidazole ligands to each copper ion to form a square-planar Cu2+ complex. This work is concerned with identification of the fourth ligand. A new (to our knowledge) electron paramagnetic resonance method based on analysis of the intense features of the electron paramagnetic resonance spectrum in the g⊥ region at 2 GHz is introduced to distinguish between three and four nitrogen ligands. The methodology was established by studies of a model system consisting of histidine imidazole ligation to Cu2+. In this spectral region at 2 GHz (S-band), g-strain and broadening from the possible rhombic character of the Zeeman interaction are small. The most intense line is identified with the MI = +1/2 extra absorption peak. Spectral simulation demonstrated that this peak is insensitive to cupric Ax and Ay hyperfine interaction. The spectral region to the high-field side of this peak is uncluttered and suitable for analysis of nitrogen superhyperfine couplings to determine the number of nitrogens. The spectral region to the low-field side of the intense extra absorption peak in the g⊥ part of the spectrum is sensitive to the rhombic distortion parameters Ax and Ay. Application of the method to the prion protein system indicates that two species are present and that the dominant species contains four nitrogen ligands. A new loop-gap microwave resonator is described that contains ∼1 mL of frozen sample. PMID:19383478

  18. NASA 60 GHz intersatellite communication link definition study. Addendum A: Mixed baseband and IF signals

    NASA Technical Reports Server (NTRS)

    1986-01-01

    As part of a definition study for a 60 GHz intersatellite communications link system (ICLS), baseline design concepts for a channelized crosslink were identified. The crosslink would allow communications between geostationary satellites of the planned Tracking and Data Acquisition System (TDAS) and would accommodate a mixture of frequency translation coherent links (bent pipe links) and baseband-in/baseband-out links (mod/demod links). A 60 GHz communication system was developed for sizing and analyzing the crosslink. For the coherent links this system translates incoming signals directly up to the 60 GHz band; trunks the signals across from one satellite to a second satellite at 60 GHz then down converts to the proper frequency for re-transmission from the second satellite without converting to any intermediate frequencies. For the baseband-in/baseband-out links the baseband data is modulated on to the 60 GHz carrier at the transmitting satellite and demodulated at the receiving satellite. The frequency plan, equipment diagrams, and link calculations are presented along with results from sizing and reliability analyses.

  19. A 2.3-GHz low-noise cryo-FET amplifier

    NASA Technical Reports Server (NTRS)

    Loreman, J.

    1988-01-01

    A cryogenic cooled, low-noise Field Effect Transistor (FET) amplifier assembly for use at 2.2 to 2.3 GHz was developed for the DSN to meet the requirements of a Very Long Baseline Interferometry (VLBI) upgrade. An amplifier assembly was developed at JPL that uses a commercial closed-cycle helium refrigerator (CCR) to cool a FET amplifier to an operating temperature of 15 K. A cooled probe waveguide-to-coaxial transition similar to that used in the research and development Ultra-Low-Noise S-band Traveling Wave Maser (TWM) is used to minimize input line losses. Typical performance includes an input flange equivalent noise contribution of 14.5 K, a gain slope of less than 0.05 dB/MHz across a bandwidth of 2.2 to 2.3 GHz, an input VSWR of 1.5:1 at 2.25 GHz, and an insertion gain of 45 + or - 1 dB across the bandwidth of 2.2 to 2.3 GHz. Three 2.3 GHz FET/CCR assemblies were delivered to the DSN in the spring of 1987.

  20. Heterodyne detection of the 752.033-GHz H2O rotational absorption line

    NASA Technical Reports Server (NTRS)

    Dionne, G. F.; Fitzgerald, J. F.; Chang, T. S.; Litvak, M. M.; Fetterman, H. R.

    1980-01-01

    A tunable high resolution two stage heterodyne radiometer was developed for the purpose of investigating the intensity and lineshape of the 752.033 GHz rotational transition of water vapor. Single-sideband system noise temperatures of approximately 45,000 K were obtained using a sensitive GaAs Schottky diode as the first stage mixer. First local oscillator power was supplied by a CO2 laser pumped formic acid laser (761.61 GHz), generating an X-band IF signal with theoretical line center at 9.5744 GHz. Second local oscillator power was provided by means of a 3 GHz waveguide cavity filter with only 9 dB insertion loss. In absorption measurements of the H2O taken from a laboratory simulation of a high altitude rocket plume, the center frequency of the 752 GHz line was determined to within 1 MHz of the reported value. A rotational temperature 75 K, a linewidth 5 MHz and a Doppler shift 3 MHz were measured with the line-of-sight intersecting the simulated-plume axis at a distance downstream of 30 nozzle diameters. These absorption data were obtained against continuum background radiation sources at temperatures of 1175 and 300 K.

  1. High power pulsed magnicon at 34-GHz

    SciTech Connect

    Nezhevenko, O.A.; Yakovlev, V.P.; Ganguly, A.K.; Hirshfield, J.L.

    1999-05-01

    A high efficiency, high power magnicon amplifier at 34.272 GHz has been designed as a radiation source to drive multi-TeV electron-positron linear colliders. Simulations show peak output power of 45 MW in a 1.5 microsecond wide pulse with an efficiency of 45{percent} and gain of 55 dB. The repetition rate is 10 Hz. The amplifier is a frequency tripler, or third harmonic amplifier, in that the output frequency of 34.272 GHz is three times the input drive frequency of 11.424 GHz. Thus the rotating TM{sub 110} modes in the drive cavity, 3 gain cavities and double decoupled penultimate cavities are resonant near 11.424 GHz; and the rotating TM{sub 310} mode in the output cavity is resonant at 34.272 GHz. A 500 kV, 200 A high area compression electron gun will provide a low emittance electron beam with a diameter of about 0.8 mm. A superconducting solenoid magnet will provide a magnetic field of 13 kG in the deflection system and 22 kG in the output cavity. A collector for the spent beam has also been designed. Detailed simulation results for the operation of the entire magnicon amplifier (gun, magnetic system, rf system and collector) will be given. {copyright} {ital 1999 American Institute of Physics.}

  2. A 12 GHZ 50 MW Klystron for Support of Accelerator Research

    SciTech Connect

    Sprehn, Daryl; Haase, Andrew; Jensen, Aaron; Jongewaard, Erik; Nantista, Christopher; Vlieks, Arnold; /SLAC

    2011-05-31

    A 12 GHz 50MW X-band klystron is under development at the SLAC National Accelerator Laboratory Klystron Department. The klystron will be fabricated to support programs currently underway at three European Labs; CERN, PSI, and INFN Trieste. The choice of frequency selection was due to the CLIC RF frequency changing from 30 GHz to the European X-band frequency of 11.99 GHz in 2008. Since the Klystron Department currently builds 50MW klystrons at 11.424 GHz known collectively as the XL4 klystrons, it was deemed cost-effective to utilize many XL4 components by leaving the gun, electron beam transport, solenoid magnet and collector unchanged. To realize the rf parameters required, the rf cavities and rf output hardware were necessarily altered. Some improvements to the rf design have been made to reduce operating gradients and increase reliability. Changes in the multi-cell output structure, waveguide components, and the window will be discussed along with testing of the devices. Five klystrons known as XL5 klystrons are scheduled for production over the next two years.

  3. 330 GHz FMCW Image Sensor for Homeland Security Applications

    NASA Astrophysics Data System (ADS)

    Kapilevich, Boris; Pinhasi, Yosef; Arusi, Ruth; Anisimov, Michael; Hardon, Danny; Litvak, Boris; Wool, Yan

    2010-11-01

    A single-pixel imaging remote sensor operating at 330 GHz is described. It is based on a frequency modulated continuous wave (FMCW) and aimed at detection of concealed objects for ranges up to 40 m. The system consists of 2 horn-lens antennas integrated with a homodyne transceiver. The synthesized linear FMCW signal at X-band is multiplied by a factor of 32 to generate the transmitted signal. An intermediate frequency (IF) signal obtained in the output port of the 2-nd harmonic mixer is employed for image processing. Distance measurements were made by performing data acquisition unit based on LabView interface and resulting in a range resolution about 1 cm. Examples of 2D and 3D images reconstructed with this sensor are presented.

  4. A 20 GHz, 75 watt helix TWT for space communications

    NASA Technical Reports Server (NTRS)

    Heney, J. F.; Tamashiro, R. N.

    1982-01-01

    A space-qualified, helix-type traveling wave tube is being developed for satellite communication systems in the frequency band of 17.7 to 21.2 GHz. The design approach stresses very high efficiency operation, but with very low distortion. The tube provides multi-mode operation, permitting CW saturated power output levels of 75 watts, 40 watt and 7.5 watts. Operation is also anticipated at 5 dB below these saturation levels to achieve the required low distortion levels. Advanced construction features include a 5 stage depressed collector, a diamond supported helix slow-wave circuit, and a type M dispenser cathode. High reliability and long life (10 years) are objectives of the tube design. The status of the development and recent experimental results are presented.

  5. Quasi-Optical 34-GHz Rf Pulse Compressor

    SciTech Connect

    Hirshfield, Jay L

    2007-06-19

    Designs have been carried out on non-high-vacuum, low-power versions of three- and four-mirror quasi-optical passive and active Ka-band pulse compressors, and prototypes built and tested based on these designs. The active element is a quasi-optical grating employing gas discharge tubes in the gratings. Power gains of about 3:1 were observed experimentally for the passive designs, and about 7:1 with the active designs. High-power, high-vacuum versions of the three-and four-mirror quasi-optical pulse compressors were built and tested at low power. These now await installation and testing using multi-MW power from the 34-GHz magnicon.

  6. Four-Way Ka-Band Power Combiner

    NASA Technical Reports Server (NTRS)

    Perez, Raul; Li, Samuel

    2007-01-01

    A waveguide structure for combining the outputs of four amplifiers operating at 35 GHz (Ka band) is based on a similar prior structure used in the X band. The structure is designed to function with low combining loss and low total reflected power at a center frequency of 35 GHz with a 160 MHz bandwidth. The structure (see figure) comprises mainly a junction of five rectangular waveguides in a radial waveguide. The outputs of the four amplifiers can be coupled in through any four of the five waveguide ports. Provided that these four signals are properly phased, they combine and come out through the fifth waveguide port.

  7. Bandwidth and gain enhancement of optically transparent 60-GHz CPW-fed antenna by using BSIS-UC-EBG structure

    NASA Astrophysics Data System (ADS)

    Wang, Ning; Tian, Huiping; Guo, Zheng; Yang, Daquan; Zhou, Jian; Ji, Yuefeng

    2015-06-01

    A method in terms of bandwidth and gain enhancement is presented for optically transparent coplanar waveguide fed (CPW-Fed) antenna, which supports unlicensed 60 GHz band (57-66 GHz) applications. The original antenna and mesh antenna in [8] were designed on a transparent material that is made of a 0.2-mm-thick fused silica 7980 Corning substrate (ɛr: 3.8 and tan δ: 0.0001). However, the peak gains of -5.3 and -5.4 dBi at 60 GHz of those antennas can be further improved. Thus, in this paper, a novel bidirectional symmetric I-shaped slot uniplanar compact electromagnetic band-gap (BSIS-UC-EBG) structure with a reflection phase band of 58.0-62.1 GHz is proposed to improve antenna performance. Based on this BSIS-UC-EBG structure, both transparent BSIS-UC-EBG antenna and transparent mesh BSIS-UC-EBG antenna with enhanced properties are presented and discussed. The analysis results show that the impedance bandwidth (the peak gain) of transparent BSIS-UC-EBG antenna and transparent mesh BSIS-UC-EBG antenna are enhanced to 36.6% (4.7 dBi) and 44.7% (5.8 dBi), respectively. In addition, we also discuss the comparison of radiation patterns at 60 GHz, and the results illustrate that the radiation patterns are basically identical.

  8. Absolutely calibrated radio polarimetry of the inner Galaxy at 2.3 and 4.8 GHz

    NASA Astrophysics Data System (ADS)

    Sun, X. H.; Gaensler, B. M.; Carretti, E.; Purcell, C. R.; Staveley-Smith, L.; Bernardi, G.; Haverkorn, M.

    2014-01-01

    We present high-sensitivity and absolutely calibrated images of diffuse radio polarization at a resolution of about 10 arcmin covering the range 10° < l < 34° and |b| < 5° at 2.3 GHz from the S-band Polarization All Sky Survey and at 4.8 GHz from the Sino-German λ6 cm polarization survey of the Galactic plane. Strong depolarization near the Galactic plane is seen at 2.3 GHz, which correlates with strong Hα emission. We ascribe the depolarization to spatial Faraday rotation measure fluctuations of about 65 rad m-2 on scales smaller than 6-9 pc. We argue that most (about 90 per cent) of the polarized emission seen at 4.8 GHz originates from a distance of 3-4 kpc in the Scutum arm and that the random magnetic field dominates the regular field there. A branch extending from the North Polar Spur towards lower latitudes can be identified from the polarization image at 4.8 GHz but only partly from the polarization image at 2.3 GHz, implying that the branch is at a distance larger than 2-3 kpc. We show that comparison of structure functions of complex polarized intensity with those of polarized intensity can indicate whether the observed polarized structures are intrinsic or caused by Faraday screens. The probability distribution function of gradients from the polarization images at 2.3 GHz indicates that the turbulence in the warm ionized medium is transonic.

  9. The Mars Observer Ka-band link experiment

    NASA Technical Reports Server (NTRS)

    Rebold, T. A.; Kwok, A.; Wood, G. E.; Butman, S.

    1994-01-01

    The Ka-Band Link Experiment was the first demonstration of a deep-space communications link in the 32- to 35-GHz band (Ka-band). It was carried out using the Mars Observer spacecraft while the spacecraft was in the cruise phase of its mission and using a 34-meter beam-waveguide research and development antenna at the Goldstone complex of the DSN. The DSN has been investigating the performance benefits of a shift from X-band (8.4 GHz) to Ka-band (32 GHz) for deep-space communications. The fourfold increase in frequency is expected to offer a factor of 3 to 10 improvement (5 to 10 dB) in signal strength for a given spacecraft transmitter power and antenna size. Until recently, the expected benefits were based on performance studies, with an eye to implementing such a link, but theory was transformed to reality when a 33.7-GHz Ka-band signal was received from the spacecraft by DSS 13. This article describes the design and implementation of the Ka-Band Link Experiment from the spacecraft to the DSS-13 system, as well as results from the Ka-band telemetry demonstration, ranging demonstration, and long-term tracking experiment. Finally, a preliminary analysis of comparative X- and Ka-band tracking results is included. These results show a 4- to 7-dB advantage for Ka-band using the system at DSS 13, assuming such obstacles as antenna pointing loss and power conversion loss are overcome.

  10. A Low Power V-Band Injection-Locked Frequency Divider in 0.13-µm Si RFCMOS Technology

    NASA Astrophysics Data System (ADS)

    Seo, Seungwoo; Rieh, Jae-Sung

    In this work, a divide-by-2 injection locked frequency divider (ILFD) operating in the V-band with a low DC power consumption has been developed in a commercial 0.13-µm Si RFCMOS technology. The bias current path was separated from the injection signal path, which enabled a small supply voltage of 0.5V, leading to a DC power consumption of only 0.31mW. To the authors' best knowledge, this is the lowest power consumption reported for mm-wave ILFDs at the point of writing. All inductors and interconnection lines were designed based on EM (electromagnetic) simulator for precise prediction of circuit performance. With varactor tuning voltage ranged for 0-1.2V, the free-running oscillation frequency varied from 27.43 to 28.06GHz. At 0dBm input power, the frequency divider exhibited a locking range of 5.8GHz from 53 to 58.8GHz without external tuning mechanism. The fabricated circuit size is 0.72mm × 0.62mm including the RF and DC supply pads.

  11. Ku-band high gain antenna

    NASA Technical Reports Server (NTRS)

    Deerkoski, L. F.

    1972-01-01

    An exposed four element array of 12.8 m diameter elements mounted on a common pedestal is the recommended ground antenna configuration in support of the 2 GHz bandwidth Ku-band downlink from tdr satellites. The array provides three channel phase monopulse tracking capability with only listening feeds in each element. The array is as cost effective as a single aperture antenna and offers significant advantages in tracking and reliability.

  12. V-band integrated quadriphase modulator

    NASA Technical Reports Server (NTRS)

    Grote, A.; Chang, K.

    1983-01-01

    A V-band integrated circuit quadriphase shift keyed modulator/exciter for space communications systems was developed. Intersatellite communications systems require direct modulation at 60 GHz to enhance signal processing capability. For most systems, particularly space applications, small and lightweight components are essential to alleviate severe system design constraints. Thus to achieve wideband, high data rate systems, direct modulation techniques at millimeter waves using solid state integrated circuit technology are an integral part of the overall technology developments.

  13. 47 CFR 25.136 - Licensing provisions for user transceivers in the 1.6/2.4 GHz, 1.5/1.6 GHz, and 2 GHz Mobile...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .../2.4 GHz Mobile-Satellite Service or 2 GHz Mobile-Satellite Service may not be operated on civil... rules and regulations in this Part and the applicable engineering standards. Prior to engaging in...

  14. 47 CFR 25.136 - Licensing provisions for user transceivers in the 1.6/2.4 GHz, 1.5/1.6 GHz, and 2 GHz Mobile...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .../2.4 GHz Mobile-Satellite Service or 2 GHz Mobile-Satellite Service may not be operated on civil... rules and regulations in this Part and the applicable engineering standards. Prior to engaging in...

  15. An FDMA system concept for 30/20 GHz high capacity domestic satellite service

    NASA Technical Reports Server (NTRS)

    Berk, G.; Jean, P. N.; Rotholz, E.; White, B. E.

    1982-01-01

    The paper summarizes a feasibility study of a multibeam FDMA satellite system operating in the 30/20 GHz band. The system must accommodate a very high volume of traffic within the restrictions of a 5 kW solar cell array and a 2.5 GHz bandwidth. Multibeam satellite operation reduces the DC power demand and allows reuse of the available bandwidth. Interferences among the beams are brought to acceptable levels by appropriate frequency assignments. A transponder design is presented; it is greatly simplified by the application of a regional concept. System analysis shows that MSK modulation is appropriate for a high-capacity system because it conserves the frequency spectrum. Rain attenuation, a serious problem in this frequency band, is combatted with sufficient power margins and with coding. Link budgets, cost analysis, and weight and power calculations are also discussed. A satellite-routed FDMA system compares favorably in performance and cost with a satellite-switched TDMA system.

  16. Forty and 80 GHz technology assessment and forecast including executive summary

    NASA Technical Reports Server (NTRS)

    Mazur, D. G.; Mackey, R. J., Jr.; Tanner, S. G.; Altman, F. J.; Nicholas, J. J., Jr.; Duchaine, K. A.

    1976-01-01

    The results of a survey to determine current demand and to forecast growth in demand for use of the 40 and 80 GHz bands during the 1980-2000 time period are given. The current state-of-the-art is presented, as well as the technology requirements of current and projected services. Potential developments were identified, and a forecast is made. The impacts of atmospheric attenuation in the 40 and 80 GHz bands were estimated for both with and without diversity. Three services for the 1980-2000 time period -- interactive television, high quality three stereo pair audio, and 30 MB data -- are given with system requirements and up and down-link calculations.

  17. A 0.4 to 10 GHz airborne electromagnetic environment survey of USA urban areas

    NASA Technical Reports Server (NTRS)

    Taylor, R. E.; Hill, J. S.

    1976-01-01

    An airborne electromagnetic-environment survey of some U.S. metropolitan areas measured terrestrial emissions within the broad frequency spectrum from 0.4 to 10 GHz. A Cessna 402 commercial aircraft was fitted with both nadir-viewing and horizon-viewing antennas and instrumentation, including a spectrum analyzer, a 35 mm continuous film camera, and a magnetic tape recorder. Most of the flights were made at a nominal altitude of 10,000 feet, and Washington, D. C., Baltimore, Philadelphia, New York, and Chicago were surveyed. The 450 to 470 MHz land-mobile UHF band is especially crowded, and the 400 to 406 MHz space bands are less active. This paper discusses test measurements obtained up to 10 GHz. Sample spectrum analyzer photograhs were selected from a total of 5,750 frames representing 38 hours of data.

  18. 0.4- to 10-GHz airborne electromagnetic-environment survey of United States urban areas

    NASA Technical Reports Server (NTRS)

    Taylor, R. E.; Hill, J. S.

    1976-01-01

    An airborne electromagnetic-environment survey of some U.S. metropolitan areas measured terrestrial emissions within the broad-frequency spectrum from 0.4 to 10 GHz. A Cessna 402 commercial aircraft was fitted with both nadir-viewing and horizon-viewing antennas and instrumentation, including a spectrum analyzer, a 35-mm continuous-film camera, and a magnetic-tape recorder. Most of the flights were made at a nominal altitude of 10,000 ft, and Washington, Baltimore, Philadelphia, New York, and Chicago were surveyed. The 450- to 470-MHz land-mobile UHF band is especially crowded, and the 400- to 406-MHz space bands are less active. Test measurements obtained up to 10 GHz are discussed. Sample spectrum-analyzer photographs were selected from a total of 5750 frames representing 38 hours of data.

  19. Feasibility studies for a wireless 60 GHz tracking detector readout

    NASA Astrophysics Data System (ADS)

    Dittmeier, S.; Schöning, A.; Soltveit, H. K.; Wiedner, D.

    2016-09-01

    The amount of data produced by highly granular silicon tracking detectors in high energy physics experiments poses a major challenge to readout systems. At high collision rates, e.g. at LHC experiments, only a small fraction of data can be read out with currently used technologies. To cope with the requirements of future or upgraded experiments new data transfer techniques are required which offer high data rates at low power and low material budget. Wireless technologies operating in the 60 GHz band or at higher frequencies offer high data rates and are thus a promising upcoming alternative to conventional data transmission via electrical cables or optical fibers. Using wireless technology, the amount of cables and connectors in detectors can be significantly reduced. Tracking detectors profit most from a reduced material budget as fewer secondary particle interactions (multiple Coulomb scattering, energy loss, etc.) improve the tracking performance in general. We present feasibility studies regarding the integration of the wireless technology at 60 GHz into a silicon tracking detector. We use spare silicon strip modules of the ATLAS experiment as test samples which are measured to be opaque in the 60 GHz range. The reduction of cross talk between links and the attenuation of reflections is studied. An estimate of the maximum achievable link density is given. It is shown that wireless links can be placed as close as 2 cm next to each other for a layer distance of 10 cm by exploiting one or several of the following measures: highly directive antennas, absorbers like graphite foam, linear polarization and frequency channeling. Combining these measures, a data rate area density of up to 11 Tb/(s·m2) seems feasible. In addition, two types of silicon sensors are tested under mm-wave irradiation in order to determine the influence of 60 GHz data transmission on the detector performance: an ATLAS silicon strip sensor module and an HV-MAPS prototype for the Mu3e

  20. Optimal GHZ Paradox for Three Qubits.

    PubMed

    Ren, Changliang; Su, Hong-Yi; Xu, Zhen-Peng; Wu, Chunfeng; Chen, Jing-Ling

    2015-01-01

    Quatum nonlocality as a valuable resource is of vital importance in quantum information processing. The characterization of the resource has been extensively investigated mainly for pure states, while relatively less is know for mixed states. Here we prove the existence of the optimal GHZ paradox by using a novel and simple method to extract an optimal state that can saturate the tradeoff relation between quantum nonlocality and the state purity. In this paradox, the logical inequality which is formulated by the GHZ-typed event probabilities can be violated maximally by the optimal state for any fixed amount of purity (or mixedness). Moreover, the optimal state can be described as a standard GHZ state suffering flipped color noise. The maximal amount of noise that the optimal state can resist is 50%. We suggest our result to be a step toward deeper understanding of the role played by the AVN proof of quantum nonlocality as a useful physical resource. PMID:26272658

  1. Optimal GHZ Paradox for Three Qubits

    PubMed Central

    Ren, Changliang; Su, Hong-Yi; Xu, Zhen-Peng; Wu, Chunfeng; Chen, Jing-Ling

    2015-01-01

    Quatum nonlocality as a valuable resource is of vital importance in quantum information processing. The characterization of the resource has been extensively investigated mainly for pure states, while relatively less is know for mixed states. Here we prove the existence of the optimal GHZ paradox by using a novel and simple method to extract an optimal state that can saturate the tradeoff relation between quantum nonlocality and the state purity. In this paradox, the logical inequality which is formulated by the GHZ-typed event probabilities can be violated maximally by the optimal state for any fixed amount of purity (or mixedness). Moreover, the optimal state can be described as a standard GHZ state suffering flipped color noise. The maximal amount of noise that the optimal state can resist is 50%. We suggest our result to be a step toward deeper understanding of the role played by the AVN proof of quantum nonlocality as a useful physical resource. PMID:26272658

  2. Optimal GHZ Paradox for Three Qubits

    NASA Astrophysics Data System (ADS)

    Ren, Changliang; Su, Hong-Yi; Xu, Zhen-Peng; Wu, Chunfeng; Chen, Jing-Ling

    2015-08-01

    Quatum nonlocality as a valuable resource is of vital importance in quantum information processing. The characterization of the resource has been extensively investigated mainly for pure states, while relatively less is know for mixed states. Here we prove the existence of the optimal GHZ paradox by using a novel and simple method to extract an optimal state that can saturate the tradeoff relation between quantum nonlocality and the state purity. In this paradox, the logical inequality which is formulated by the GHZ-typed event probabilities can be violated maximally by the optimal state for any fixed amount of purity (or mixedness). Moreover, the optimal state can be described as a standard GHZ state suffering flipped color noise. The maximal amount of noise that the optimal state can resist is 50%. We suggest our result to be a step toward deeper understanding of the role played by the AVN proof of quantum nonlocality as a useful physical resource.

  3. A 30 GHz monolithic receive module

    NASA Technical Reports Server (NTRS)

    Mondal, J.; Contolatis, T.; Geddes, J.; Bauhahn, P.; Sokolov, V.

    1990-01-01

    The technical achievements and deliveries made during the duration of the program to develop a 30 GHz monolithic receive module for communication feed array applications and to deliver submodules and 30 GHz monolithic receive modules for experimental evaluation are discussed. Key requirements include an overall receive module noise figure of 5 dB, a 30 dB RF-to-RF gain with six levels of intermediate gain control, a five bit phase shifter, and a maximum power consumption of 250 mW. In addition, the monolithic receive module design addresses a cost goal of less than one thousand dollars (1980 dollars) per module in unit buys of 5,000 or more, and a mechanical configuration that is applicable to a spaceborne phase array system. An additional task for the development and delivery of 32 GHz phase shifter integrated circuit (IC) for deep space communication is also described.

  4. V-band low-noise integrated circuit receiver. [for space communication systems

    NASA Technical Reports Server (NTRS)

    Chang, K.; Louie, K.; Grote, A. J.; Tahim, R. S.; Mlinar, M. J.; Hayashibara, G. M.; Sun, C.

    1983-01-01

    A compact low-noise V-band integrated circuit receiver has been developed for space communication systems. The receiver accepts an RF input of 60-63 GHz and generates an IF output of 3-6 GHz. A Gunn oscillator at 57 GHz is phaselocked to a low-frequency reference source to achieve high stability and low FM noise. The receiver has an overall single sideband noise figure of less than 10.5 dB and an RF to IF gain of 40 dB over a 3-GHz RF bandwidth. All RF circuits are fabricated in integrated circuits on a Duroid substrate.

  5. 95 GHz gyrotron with ferroelectric cathode.

    PubMed

    Einat, M; Pilossof, M; Ben-Moshe, R; Hirshbein, H; Borodin, D

    2012-11-01

    Ferroelectric cathodes were reported as a feasible electron source for microwave tubes. However, due to the surface plasma emission characterizing this cathode, operation of millimeter wave tubes based on it remains questionable. Nevertheless, the interest in compact high power sources of millimeter waves and specifically 95 GHz is continually growing. In this experiment, a ferroelectric cathode is used as an electron source for a gyrotron with the output frequency extended up to 95 GHz. Power above a 5 kW peak and ~0.5 μs pulses are reported; a duty cycle of 10% is estimated to be achievable. PMID:23215293

  6. 17 GHz High Gradient Accelerator Research

    SciTech Connect

    Temkin, Richard J.; Shapiro, Michael A.

    2013-07-10

    This is a report on the MIT High Gradient Accelerator Research program which has included: Operation of the 17 GHz, 25 MeV MIT/Haimson Research Corp. electron accelerator at MIT, the highest frequency, stand-alone accelerator in the world; collaboration with members of the US High Gradient Collaboration, including the design and test of novel structures at SLAC at 11.4 GHz; the design, construction and testing of photonic bandgap structures, including metallic and dielectric structures; the investigation of the wakefields in novel structures; and the training of the next generation of graduate students and postdoctoral associates in accelerator physics.

  7. A 260-340 GHz Dual Chip Frequency Tripler for THz Frequency Multiplier Chains

    NASA Technical Reports Server (NTRS)

    Maestrini, Alain; Tripon-Canseliet, Charlotte; Ward, John S.; Gill, John J.; Mehdi, Imran

    2006-01-01

    We designed and fabricated a fix-tuned balanced frequency tripler working in the 260-340 GHz band to be the first stage of a x3x3x3 multiplier chain to 2.7 THz. The design of a dual-chip version of this multiplier featuring an input splitter / output combiner as part of the input / output matching networks of both chips - with no degradation of the expected bandwidth and efficiency- will be presented.

  8. Compact filtering monopole patch antenna with dual-band rejection.

    PubMed

    Kim, Sun-Woong; Choi, Dong-You

    2016-01-01

    In this paper, a compact ultra-wideband patch antenna with dual-band rejection is proposed. The proposed antenna filters 3.3-3.8 GHz WiMAX and 5.15-5.85 GHz WLAN by respectively rejecting these bands through a C-shaped slit and a λg/4 resonator. The λg/4 resonator is positioned as a pair, centered around the microstrip line, and a C-type slit is inserted into an elliptical patch. The impedance bandwidth of the proposed antenna is 2.9-9.3 GHz, which satisfies the bandwidth for ultra-wideband communication systems. Further, the proposed antenna provides dual-band rejection at two bands: 3.2-3.85 and 4.7-6.03 GHz. The radiation pattern of the antenna is omnidirectional, and antenna gain is maintained constantly while showing -8.4 and -1.5 dBi at the two rejected bands, respectively. PMID:27386331

  9. 47 CFR 25.136 - Licensing provisions for user transceivers in the 1.6/2.4 GHz, 1.5/1.6 GHz, and 2 GHz Mobile...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Footnote 5.353A in 47 CFR 2.106 and the priority and real-time preemption requirements imposed by Footnote... the 1.6/2.4 GHz, 1.5/1.6 GHz, and 2 GHz Mobile-Satellite Services. 25.136 Section 25.136 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE...

  10. AMMONIA AND CO OBSERVATIONS TOWARD LOW-LUMINOSITY 6.7 GHz METHANOL MASERS

    SciTech Connect

    Wu, Y. W.; Xu, Y.; Yang, J.; Zhang, S. B.; Pandian, J. D.; Henkel, C.; Menten, K. M.

    2010-09-01

    To investigate whether distinctions exist between low- and high-luminosity Class II 6.7 GHz methanol masers, we have undertaken multi-line mapping observations of various molecular lines, including the NH{sub 3} (1,1), (2,2), (3,3), (4,4), and {sup 12}CO (1-0) transitions, toward a sample of nine low-luminosity 6.7 GHz masers and {sup 12}CO (1-0) observations toward a sample of eight high-luminosity 6.7 GHz masers, for which we already had NH{sub 3} spectral line data. Emission in the NH{sub 3} (1,1), (2,2), and (3,3) transitions was detected in eight out of nine low-luminosity maser sources, in which 14 cores were identified. We derive densities, column densities, temperatures, core sizes, and masses of both low- and high-luminosity maser regions. A comparative analysis of the physical quantities reveals marked distinctions between the low-luminosity and high-luminosity groups: in general, cores associated with high-luminosity 6.7 GHz masers are larger and more massive than those traced by low-luminosity 6.7 GHz masers; regions traced by the high-luminosity masers have larger column densities but lower densities than those of the low-luminosity maser regions. Further, strong correlations between 6.7 GHz maser luminosity and NH{sub 3} (1,1) and (2,2) line widths are found, indicating that internal motions in high-luminosity maser regions are more energetic than those in low-luminosity maser regions. A {sup 12}CO (1-0) outflow analysis also shows distinctions in that outflows associated with high-luminosity masers have wider line wings and larger sizes than those associated with low-luminosity masers.

  11. The 20 GHz GaAs monolithic power amplifier module development

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The development of a 20 GHz GaAs FET monlithic power amplifier module for advanced communication applications is described. Four-way power combing of four 0.6 W amplifier modules is used as the baseline approach. For this purpose, a monolithic four-way traveling-wave power divider/combiner was developed. Over a 20 GHz bandwidth (10 to 30 GHz), an insertion loss of no more than 1.2 dB was measured for a pair of back-to-back connected divider/combiners. Isolation between output ports is better than 20 dB, and VSWRs are better than 21:1. A distributed amplifier with six 300 micron gate width FETs and gate and drain transmission line tapers has been designed, fabricated, and evaluated for use as an 0.6 W module. This amplifier has achieved state-of-the-art results of 0.5 W output power with at least 4 dB gain across the entire 2 to 21 GHz frequency range. An output power of 2 W was achieved at a measurement frequency of 18 GHz when four distributed amplifiers were power-combined using a pair of traveling-wave divider/combiners. Another approach is the direct common-source cascading of three power FET stages. An output power of up to 2W with 12 dB gain and 20% power-added efficiency has been achieved with this approach (at 17 GHz). The linear gain was 14 dB at 1 W output. The first two stages of the three-stage amplifier have achieved an output power of 1.6 W with 9 dB gain and 26% power-added efficiency at 16 GHz.

  12. A 670 GHz gyrotron with record power and efficiency

    NASA Astrophysics Data System (ADS)

    Glyavin, M. Yu.; Luchinin, A. G.; Nusinovich, G. S.; Rodgers, J.; Kashyn, D. G.; Romero-Talamas, C. A.; Pu, R.

    2012-10-01

    A 670 GHz gyrotron with record power and efficiency has been developed in joint experiments of the Institute of Applied Physics, Russian Academy of Sciences (Nizhny Novgord, Russia), and the University of Maryland (USA) teams. The magnetic field of 27-28 T required for operation at the 670 GHz at the fundamental cyclotron resonance is produced by a pulsed solenoid. The pulse duration of the magnetic field is several milliseconds. A gyrotron is driven by a 70 kV, 15 A electron beam, so the beam power is on the order of 1 MW in 10-20 ms pulses. The ratio of the orbital to axial electron velocity components is in the range of 1.2-1.3. The gyrotron is designed to operate in the TE31,8-mode. Operation in a so high-order mode results in relatively low ohmic losses (less than 10% of the radiated power). Achieved power of the outgoing radiation (210 kW) and corresponding efficiency (about 20%) represent record numbers for high-power sources of sub-THz radiation.

  13. Moving target imaging by both Ka-band and Ku-band high-resolution radars

    NASA Astrophysics Data System (ADS)

    Zhang, Yunhua; Zhai, Wenshuai; Zhang, Xiangkun; Shi, Xiaojin; Gu, Xiang; Jiang, Jingshan

    2011-11-01

    The experimental work on testing the wide-band transmitters and receivers developed for Ka-band and Ku-band radar systems, as well as the signal processing algorithms were introduced. A city light-railway train was selected as the imaged target. The wide-band transmitters and receivers were designed based on the stepped-frequency chirp signal (SFCS) with 2GHz bandwidth synthesized. The Super-SVA technique was used to deal with the case of transmitting SFCS with band gaps between subchirps for purpose of achieving the same bandwidth using as less as possible subpulses. Both Ka-band and Ku-band high-resolution radar images were obtained, which show that Ka-band images are much clear than that of Ku-band as we expect. There are two reasons to explaining this, one reason is due to the electromagnetic scattering of train itself are different for Ka-band and Ku-band frequencies, and the other reason is due to the interactions, i.e. multi-reflection or multi-scattering between the train and the side metal fences or the lamp post are different.

  14. W-band Phased Array Systems using Silicon Integrated Circuits

    NASA Astrophysics Data System (ADS)

    Kim, Sang Young

    This thesis presents the silicon-based on-chip W-band phased array systems. An improved quadrature all-pass filter (QAF) and its implementation in 60--80 GHz active phase shifter using 0.13 microm SiGe BiCMOS technology is presented. It is demonstrated that with the inclusion of an Rs/R in the high Q branches of C and L, the sensitivity to the loading capacitance, therefore the I/Q phase and amplitude errors are minimized. This technique is especially suited for wideband millimeter-wave circuits where the loading capacitance (CL) is comparable to the filter capacitance (C). A prototype 60--80 GHz active phased shifter using the improved QAF is demonstrated. The overall chip size is 1.15 x 0.92 mm2 with the power consumption of 108 mW. The measured S11 and S22 are < -10 dB at 60--80 GHz and 60--73 GHz, respectively. The measured average power gain is 11.0--14.7 dB at 60--79 GHz with the rms gain error of < 1.3 dB at 60--78 GHz for 4-bit phase states. And the rms phase error is < 9.1 degree at 60--78.5 GHz showing wideband 4-bit performance. The measured NF is 9--11.6 dB at 63--75 GHz and the measured P 1dB is -27 dBm at 70 GHz. In another project, a 67--78 GHz 4-bit passive phase shifter using 0.13 microm CMOS switches is demonstrated. The phase shifter is based on a low-pass pi-network. The chip size is 0.45 x 0.3 mm2 without pads and consumes virtually no power. The measured S11 and S22 is < -10 dB at 67--81 GHz for all 16 phase states. The measured gain of 4-bit phase shifter is -19.2 +/- 3.7 dB at 77 GHz with the rms gain error of < 11.25 degree at 67--78 GHz. And the measured rms phase error is < 2.5 dB at 67--78 GHz. The measured P1dB is > 8 dBm and the simulated IIP3 is > 22 dBm. A low-power 76--84 GHz 4-element phased array receiver using the designed passive phase shifter is presented. The power consumption is minimized by using a single-ended design and alternating the amplifiers and phase shifter cells to result in a low noise figure at a low power

  15. Fluorinated graphene oxide for enhanced S and X-band microwave absorption

    NASA Astrophysics Data System (ADS)

    Sudeep, P. M.; Vinayasree, S.; Mohanan, P.; Ajayan, P. M.; Narayanan, T. N.; Anantharaman, M. R.

    2015-06-01

    Here we report the microwave absorbing properties of three graphene derivatives, namely, graphene oxide (GO), fluorinated GO (FGO, containing 5.6 at. % Fluorine (F)), and highly FGO (HFGO, containing 23 at. % F). FGO is known to be exhibiting improved electrochemical and electronic properties when compared to GO. Fluorination modifies the dielectric properties of GO and hence thought of as a good microwave absorber. The dielectric permittivities of GO, FGO, and HFGO were estimated in the S (2 GHz to 4 GHz) and X (8 GHz to 12 GHz) bands by employing cavity perturbation technique. For this, suspensions containing GO/FGO/HFGO were made in N-Methyl Pyrrolidone (NMP) and were subjected to cavity perturbation. The reflection loss was then estimated and it was found that -37 dB (at 3.2 GHz with 6.5 mm thickness) and -31 dB (at 2.8 GHz with 6 mm thickness) in the S band and a reflection loss of -18 dB (at 8.4 GHz with 2.5 mm thickness) and -10 dB (at 11 GHz with 2 mm thickness) in the X band were achieved for 0.01 wt. % of FGO and HFGO in NMP, respectively, suggesting that these materials can serve as efficient microwave absorbers even at low concentrations.

  16. Commissioning of the superconducting ECR ion source VENUS at 18 GHz

    SciTech Connect

    Leitner, Daniela; Abbott, Steven R.; Dwinell, Roger D.; Leitner, Matthaeus; Taylor, Clyde E.; Lyneis, Claude M.

    2004-06-01

    During the last year, the VENUS ECR ion source was commissioned at 18 GHz and preparations for 28 GHz operation are now underway. During the commissioning phase with 18 GHz, tests with various gases and metals have been performed with up to 2000 W RF power. The ion source performance is very promising [1,2]. VENUS (Versatile ECR ion source for Nuclear Science) is a next generation superconducting ECR ion source, designed to produce high current, high charge state ions for the 88-Inch Cyclotron at the Lawrence Berkeley National Laboratory. VENUS also serves as the prototype ion source for the RIA (Rare Isotope Accelerator) front end. The goal of the VENUS ECR ion source project as the RIA R&D injector is the production of 240e{micro}A of U{sup 30+}, a high current medium charge state beam. On the other hand, as an injector ion source for the 88-Inch Cyclotron the design objective is the production of 5e{micro}A of U{sup 48+}, a low current, very high charge state beam. To meet these ambitious goals, VENUS has been designed for optimum operation at 28 GHz. This frequency choice has several design consequences. To achieve the required magnetic confinement, superconducting magnets have to be used. The size of the superconducting magnet structure implies a relatively large plasma volume. Consequently, high power microwave coupling becomes necessary to achieve sufficient plasma heating power densities. The 28 GHz power supply has been delivered in April 2004.

  17. Experimental study of a megawatt 200--300 GHz gyrotron oscillator

    SciTech Connect

    Grimm, T.L.; Kreischer, K.E.; Temkin, R.J. )

    1993-11-01

    A detailed experimental study is presented of a pulsed megawatt gyrotron oscillator operating in the 200--300 GHz range, whose design is consistent with continuous operation for electron cyclotron resonance heating (ECRH) of fusion plasmas. Two different radii beams produced by magnetron injection guns (MIG's) were used to excite the cylindrical waveguide cavity. The emission was found experimentally to be single mode, single frequency with a single rotation, which can be mode converted for transmission. The highest power reached with the larger radius electron beam was 1.2 MW at 230 GHz in the TE[sub 34,6] mode with an efficiency of 20% and beam parameters of 59 A and 100 kV. The highest power reached with the smaller radius electron beam was 0.78 MW at 280 GHz in the TE[sub 25,13] mode with an efficiency of 17% and beam parameters of 51 A and 92 kV. The smaller radius beam gave a peak efficiency of 18% at 0.72 MW, 290 GHz in the TE[sub 25,14] mode. Efficiencies obtained in this experiment are about half that of less highly overmoded gyrotrons. Analysis of the experiment suggests that the low efficiency is primarily caused by azimuthal mode competition, in agreement with multimode theory for a tapered cavity. These experimental results show that megawatt power levels can be generated in continuous wave (cw) gyrotron oscillators at 200--300 GHz with efficiencies approaching 20%.

  18. Customer premise service study for 30/20 GHz satellite system

    NASA Technical Reports Server (NTRS)

    Milton, R. T.; Ross, D. P.; Harcar, A. R.; Freedenberg, P.; Schoen, D.

    1983-01-01

    Satellite systems in which the space segment operates in the 30/20 GHz frequency band are defined and compared as to their potential for providing various types of communications services to customer premises and the economic and technical feasibility of doing so. Technical tasks performed include: market postulation, definition of the ground segment, definition of the space segment, definition of the integrated satellite system, service costs for satellite systems, sensitivity analysis, and critical technology. Based on an analysis of market data, a sufficiently large market for services is projected so as to make the system economically viable. A large market, and hence a high capacity satellite system, is found to be necessary to minimize service costs, i.e., economy of scale is found to hold. The wide bandwidth expected to be available in the 30/20 GHz band, along with frequency reuse which further increases the effective system bandwidth, makes possible the high capacity system. Extensive ground networking is required in most systems to both connect users into the system and to interconnect Earth stations to provide spatial diversity. Earth station spatial diversity is found to be a cost effective means of compensating the large fading encountered in the 30/20 GHz operating band.

  19. Common base amplifier with 7 - dB gain at 176 GHz in InP mesa DHBT technology

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene; Paidi, V.; Griffith, Z.; Dahlstrom, M.; Wei, Y.; Urteaga, M.; Rodell, M. J. W.; Fung, A.

    2004-01-01

    We report a single stage tunded amplifier that exhibits 7 dB small signal gain at 176 GHz. Common Base topology is chosen as it has the best maximum stable gain (MSG) in this frequency band when compared to common emitter and common collector topologies. The amplifiers are designed and fabricated in InP mesa double heterojunction bipolar transistor (DHBT) technology.

  20. A 0.8-4.2 GHz monolithic all-digital PLL based frequency synthesizer for wireless communications

    NASA Astrophysics Data System (ADS)

    Yuanxin, Zhao; Yuanpei, Gao; Wei, Li; Ning, Li; Junyan, Ren

    2015-01-01

    A 0.8-4.2 GHz monolithic all-digital PLL based frequency synthesizer for wireless communications is successfully realized by the 130 nm CMOS process. A series of novel methods are proposed in this paper. Two band DCOs with high frequency resolution are utilized to cover the frequency band of interest, which is as wide as 2.5 to 5 GHz. An overflow counter is proposed to prevent the “pulse-swallowing” phenomenon so as to significantly reduce the locking time. A NTW-clamp digital module is also proposed to prevent the overflow of the loop control word. A modified programmable divider is presented to prevent the failure operation at the boundary. The measurement results show that the output frequency range of this frequency synthesizer is 0.8-4.2 GHz. The locking time achieves a reduction of 84% at 2.68 GHz. The best in-band and out-band phase noise performances have reached -100 dBc/Hz, and -125 dBc/Hz respectively. The lowest reference spur is -58 dBc.

  1. Long-term amplitude and phase stability of the 400-kW 2.115-GHz transmitter

    NASA Technical Reports Server (NTRS)

    Hoppe, D. J.; Bhanji, A. M.

    1986-01-01

    Results of recent measurements of the long-term phase, amplitude and group delay stability of the 400-kW S-band (2.115-GHz) transmitter are reported. Various control parameters which are responsible for many of the observed instabilities are identified. Further tests to identify the parameters responsible for the remaining instabilities are suggested.

  2. Multi-band polarization independent cylindrical metamaterial absorber and sensor application

    NASA Astrophysics Data System (ADS)

    Dincer, Furkan; Karaaslan, Muharrem; Colak, Sule; Tetik, Erkan; Akgol, Oguzhan; Altıntas, Olcay; Sabah, Cumali

    2016-03-01

    A multi-band perfect metamaterial absorber (MA) based on a cylindrical waveguide with polarization independency is numerically presented and investigated in detail. The proposed absorber has a very simple configuration, and it operates at flexible frequency ranges within the microwave frequency regime by simply tuning the dimensions of the structure. The maximum absorption values are obtained as 99.9%, 97.5%, 85.8%, 68.2% and 40.2% at the frequencies of 1.34 GHz, 2.15 GHz, 3.2 GHz, 4.31 GHz and 5.41 GHz, respectively. The numerical studies verify that the proposed model can provide multi-band perfect absorptions at wide polarization and incident angles due to its rotational symmetry feature. We have also realized sensor and parametric study applications in order to show additional features of the suggested model. The suggested MA enables myriad potential applications in medical technologies, sensors and in defense industry etc.

  3. Harmonic measurements of the Galileo spacecraft X-band transmitter system

    NASA Technical Reports Server (NTRS)

    Stanton, P. H.; Manshadi, F.

    1987-01-01

    Harmonics of X-band (8.4 GHz) spacecraft transmitter systems can be used to measure the performance characteristics of higher frequency deep space communication links. The Galileo X-band transmitter system was measured at the second, third, and fourth harmonics (16.8, 25.2, and 33.6 GHz, respectively). The effective isotropic radiated power was determined to be approximately 52 dBm at 16.8 GHz, 47 dBm at 25.2 GHz, and 25 dBm at 33.6 GHz. These values can be useful, depending upon the sensitivity of the Earth-based receiving system and the distance of the spacecraft from Earth.

  4. 1,2,4-Tribromobenzene

    Integrated Risk Information System (IRIS)

    1,2,4 - Tribromobenzene ; CASRN 615 - 54 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcin

  5. 1,2,3-Trichloropropane

    Integrated Risk Information System (IRIS)

    1,2,3 - Trichloropropane ; CASRN 96 - 18 - 4 Human health assessment information on a chemical substance is included in IRIS only after a comprehensive review of toxicity data by U.S . EPA health scientists from several program offices , regional offices , and the Office of Research and Development

  6. trans-1,2-Dichloroethylene

    Integrated Risk Information System (IRIS)

    trans - 1,2 - Dichloroethylene ; CASRN 156 - 60 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for No

  7. 1,1,2-Trichloropropane

    Integrated Risk Information System (IRIS)

    1,1,2 - Trichloropropane ; CASRN 598 - 77 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarci

  8. 1,1,2-Trichloroethane

    Integrated Risk Information System (IRIS)

    1,1,2 - Trichloroethane ; CASRN 79 - 00 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcino

  9. 1,2,4-Trichlorobenzene

    Integrated Risk Information System (IRIS)

    1,2,4 - Trichlorobenzene ; CASRN 120 - 82 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarci

  10. cis-1,2-Dichloroethylene

    Integrated Risk Information System (IRIS)

    cis - 1,2 - Dichloroethylene ; CASRN 156 - 59 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Nonc

  11. 1,2-Epoxybutane (EBU)

    Integrated Risk Information System (IRIS)

    1,2 - Epoxybutane ( EBU ) ; CASRN 106 - 88 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarc

  12. A GPU-Based Wide-Band Radio Spectrometer

    NASA Astrophysics Data System (ADS)

    Chennamangalam, Jayanth; Scott, Simon; Jones, Glenn; Chen, Hong; Ford, John; Kepley, Amanda; Lorimer, D. R.; Nie, Jun; Prestage, Richard; Roshi, D. Anish; Wagner, Mark; Werthimer, Dan

    2014-12-01

    The graphics processing unit has become an integral part of astronomical instrumentation, enabling high-performance online data reduction and accelerated online signal processing. In this paper, we describe a wide-band reconfigurable spectrometer built using an off-the-shelf graphics processing unit card. This spectrometer, when configured as a polyphase filter bank, supports a dual-polarisation bandwidth of up to 1.1 GHz (or a single-polarisation bandwidth of up to 2.2 GHz) on the latest generation of graphics processing units. On the other hand, when configured as a direct fast Fourier transform, the spectrometer supports a dual-polarisation bandwidth of up to 1.4 GHz (or a single-polarisation bandwidth of up to 2.8 GHz).

  13. On board low noise 30 GHz receiver

    NASA Astrophysics Data System (ADS)

    Dambrosio, A.; Castelli, G.; Mazzini, C.

    An advanced receiver for onboard application in a 30/20 GHz SS-TDMA satellite communication system is described. The basic requirements of the receiver are a total noise temperature of 1000 K and a bandwidth of 250 MHz. Attention is given to system requirements, the receiver configuration, the parametric preamplifier, and the down converter and IF preamplifier.

  14. Propagation handbook, frequencies above 10 GHz

    NASA Technical Reports Server (NTRS)

    Ippolito, Louis J.

    1988-01-01

    The progress and accomplishments in the developmet of the Fourth Edition of the NASA Propagation Effects Handbook for Satellite Systems Design, for frequencies 10 to 100 GHz, NASA Reference Publication 1082(04), dated May 1988, prepared by Westighouse Electric Corporation for the Jet Propulsion Laboratory are discussed.

  15. Gyroharmonic Conversion at 11.4 GHz

    NASA Astrophysics Data System (ADS)

    Lapointe, M. A.; Wang, Changbiao; Yoder, R. B.; Ganguly, A. K.; Wang, Mei; Hirshfield, J. L.

    1997-11-01

    First results on the generation of 11.4 GHz microwaves by gyroharmonic conversion are presented. A helical rotating beam is prepared in a 2.857 GHz cyclotron autoresonant accelerator (CARA(M.A. LaPointe, R.B. Yoder, Changbiao Wang, A.K. Ganguly and J.L. Hirshfield, Phys. Rev. Lett. 76), 2718 (1996); J.L. Hirshfield, M.A. LaPointe, A.K. Ganguly, R.B. Yoder and Changbiao Wang, Phys. Plasmas 3, 2163 (1996).). The resulting 27A, 190 kV beam is injected into a cavity whose TE_411 mode is resonant at the 4th harmonic of the CARA drive frequency. With an appropriate magnetic field profile, power at 11.428 GHz has been observed. The spectrum at the 4th harmonic has a FWHM of 400 kHz, the Fourier limit for a 3 μsec pulse. Calorimeter measurements give an 11.4 GHz power level of about 300 kW, more than 20 dB above the nearest competing mode (TE_311). These results are compared with theory, especially regarding spreads in beam guiding center and axial velocity.

  16. Dual-band quasi-zero refraction and negative refraction in coin-shaped metamaterial

    NASA Astrophysics Data System (ADS)

    Zhang, Min; Hou, Zhi-Ling; Liu, Ya-Min; Li, Zhong-Jun; Liu, Xingda; Fang, Hui-Min

    2015-05-01

    This paper demonstrates a metamaterial capable of realizing a dual-band quasi-zero refractive index and a negative refractive index, which consists of a coin-shaped slice and two parallel planar wires. The zero refractive index is achieved over a very wide frequency range. The bandwidth of the first band of the quasi-zero index can reach up to 3 GHz, and the width of the second band exhibiting low loss is 0.4 GHz. Between these two bands, the negative refractive index band is 9.0-13.9 GHz. The corresponding formulas of electric plasma frequency and magnetic plasma frequency are established, and the theoretical results agree well with the simulated results. The proposed metamaterial may have potential applications in multiband or broadband devices.

  17. Real-time dual-band wireless videos in millimeter-wave radio-over-fiber system

    NASA Astrophysics Data System (ADS)

    Cheng, Lin; Liu, Cheng; Dong, Ze; Wang, Jing; Zhu, Ming; Chang, Gee-Kung

    2013-12-01

    A dual-band converged radio-over-fiber (RoF) access system at 60-GHz and 100-GHz millimeter-wave (mm-wave) is proposed. Real-time end-to-end delivery of two channels of independent high-definition (HD) video services simultaneously carried on 60-GHz and 100-GHz radios is demonstrated for the first time. PRBS data transmission with equivalent data rate and format is also tested to characterize the system performance. The analysis of the spectrum from the beating signal indicates the entire 60-GHz band and the W-band can be retrieved without interference. The real-time HD video display and error-free (BER < 10-9) data transmission demonstrate the feasibility of the proposed wireless access system using converged fiber-optic and mm-wave RoF techniques.

  18. A dual-band antenna feed design using a fundamental-mode coupler

    NASA Astrophysics Data System (ADS)

    Carpenter, Earl

    1992-03-01

    By means of a feed system that uses 0-dB directional couplers to inject 11- and 14 GHz fundamental mode signals into a 54-mm diameter circular waveguide, the present dual-feed system allows an earth station antenna to simultaneously operate in the 4/6 GHz and 11/14 GHz Intelsat bands. Since the 4/6 GHz signals can propagate through the Ku-band couplers with only minor perturbations, this approach permits the use of a simple C-band diplexing and polarization network that is low cost and compact, as well as adaptable for various applications. Attention is given to measured performance levels for this system; compatibility with Intelsat is demonstrated.

  19. A 10 GHz bandwidth, single transient, digitized oscilloscope with 20 GHz capability

    SciTech Connect

    Hudson, C.L.; Kocimski, S.M.; Spector, J.; Thomas, J.B.; Woodstra, R.R.

    1993-12-31

    EG&G/EM has developed an oscilloscope with a {minus}3 dB bandwidth greater than 10 GHz. Its rolloff characteristics are such that single-transient data greater than 20 GHz may be captured. A demountable CCD camera records the oscilloscope trace and is provided with PC-compatible capture and data processing software. The capabilities of the oscilloscope, camera, and its processing software are described and examples of the system`s performance is shown.

  20. RF environment survey of Space Shuttle related EEE frequency bands

    NASA Technical Reports Server (NTRS)

    Simpson, J.; Prigel, B.; Postelle, J.

    1977-01-01

    Radio frequency assignments within the continental United States in frequency bands between 121 MHz abd 65 GHz were surveyed and analyzed in order to determine current utilization of anticipated frequency bands for the shuttle borne electromagnetic environment experiment. Data from both government and nongovernment files were used. Results are presented in both narrative form and in histograms which show the total number of unclassified assignments versus frequency and total assigned power versus frequency.