Science.gov

Sample records for 470-512 mhz uhf-tv

  1. 47 CFR 90.305 - Location of stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.305 Location of... UHF TV channels separated by 2, 3, 4, 5, 7, and 8 TV channels from the television channel in which...

  2. 47 CFR 90.305 - Location of stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.305 Location of... UHF TV channels separated by 2, 3, 4, 5, 7, and 8 TV channels from the television channel in which...

  3. 47 CFR 90.305 - Location of stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.305 Location of... UHF TV channels separated by 2, 3, 4, 5, 7, and 8 TV channels from the television channel in which...

  4. 47 CFR 90.305 - Location of stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.305 Location of... UHF TV channels separated by 2, 3, 4, 5, 7, and 8 TV channels from the television channel in which...

  5. 47 CFR 90.305 - Location of stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.305 Location of... UHF TV channels separated by 2, 3, 4, 5, 7, and 8 TV channels from the television channel in which...

  6. 47 CFR 90.307 - Protection criteria.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., where protection will be in accordance with the values set forth in tables B and E in 47 CFR 90.309. (b... 47 Telecommunication 5 2012-10-01 2012-10-01 false Protection criteria. 90.307 Section 90.307... MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.307 Protection...

  7. 47 CFR 90.311 - Frequencies.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Frequencies. 90.311 Section 90.311... MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.311 Frequencies. (a) Except as provided for in § 90.315 and except for those frequencies allocated to services in part 22...

  8. 47 CFR 90.311 - Frequencies.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequencies. 90.311 Section 90.311... MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.311 Frequencies. (a) Except as provided for in § 90.315 and except for those frequencies allocated to services in part 22...

  9. 47 CFR 90.311 - Frequencies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Frequencies. 90.311 Section 90.311... MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.311 Frequencies. (a) Except as provided for in § 90.315 and except for those frequencies allocated to services in part 22...

  10. 47 CFR 90.311 - Frequencies.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Frequencies. 90.311 Section 90.311... MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.311 Frequencies. (a) Except as provided for in § 90.315 and except for those frequencies allocated to services in part 22...

  11. 47 CFR 90.313 - Frequency loading criteria.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Frequency loading criteria. 90.313 Section 90.313 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) §...

  12. 47 CFR 90.313 - Frequency loading criteria.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequency loading criteria. 90.313 Section 90.313 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) §...

  13. 47 CFR 90.313 - Frequency loading criteria.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Frequency loading criteria. 90.313 Section 90.313 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) §...

  14. 47 CFR 90.301 - Scope.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Scope. 90.301 Section 90.301 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.301 Scope. This subpart governs...

  15. 47 CFR 90.313 - Frequency loading criteria.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Frequency loading criteria. 90.313 Section 90.313 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) §...

  16. 47 CFR 90.301 - Scope.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Scope. 90.301 Section 90.301 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.301 Scope. This subpart governs...

  17. 47 CFR 90.301 - Scope.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Scope. 90.301 Section 90.301 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.301 Scope. This subpart governs...

  18. 47 CFR 90.301 - Scope.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Scope. 90.301 Section 90.301 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.301 Scope. This subpart governs...

  19. 47 CFR 90.313 - Frequency loading criteria.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequency loading criteria. 90.313 Section 90.313 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) §...

  20. 47 CFR 90.301 - Scope.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Scope. 90.301 Section 90.301 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.301 Scope. This subpart governs...

  1. 75 FR 3622 - Revisions to Rules Authorizing the Operation of Low Power Auxiliary Stations in the 698-806 MHz...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-22

    ... Stations in the 698-806 MHz Band; Public Interest Spectrum Coalition, Petition for Rulemaking Regarding Low... decisions in this Report and Order and of the need to clear the 700 MHz Band so that the spectrum can be...] will not be allowed to use * * * in the UHF-TV band due to a recent spectrum reallocation of...

  2. 47 CFR 15.242 - Operation in the bands 174-216 MHz and 470-668 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... of any of the other radio astronomy observatories noted in footnote US385 of Section 2.106 of this... astronomy observatory before the equipment can be installed or operated. The National Science Foundation... mobile stations operating under part 90 of this chapter in the 470-512 MHz band, and radio...

  3. 47 CFR 15.242 - Operation in the bands 174-216 MHz and 470-668 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... of any of the other radio astronomy observatories noted in footnote US 311 of Section 2.106 of this... astronomy observatory before the equipment can be installed or operated. The National Science Foundation... mobile stations operating under part 90 of this chapter in the 470-512 MHz band, and radio...

  4. 47 CFR 15.242 - Operation in the bands 174-216 MHz and 470-668 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... of any of the other radio astronomy observatories noted in footnote US385 of Section 2.106 of this... astronomy observatory before the equipment can be installed or operated. The National Science Foundation... mobile stations operating under part 90 of this chapter in the 470-512 MHz band, and radio...

  5. 47 CFR 15.242 - Operation in the bands 174-216 MHz and 470-668 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of any of the other radio astronomy observatories noted in footnote US 311 of Section 2.106 of this... astronomy observatory before the equipment can be installed or operated. The National Science Foundation... mobile stations operating under part 90 of this chapter in the 470-512 MHz band, and radio...

  6. 47 CFR 15.242 - Operation in the bands 174-216 MHz and 470-668 MHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of any of the other radio astronomy observatories noted in footnote US 311 of Section 2.106 of this... astronomy observatory before the equipment can be installed or operated. The National Science Foundation... mobile stations operating under part 90 of this chapter in the 470-512 MHz band, and radio...

  7. 47 CFR 90.175 - Frequency coordinator requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... contour of a proposed station would overlap the service contour of a station on a frequency formerly... add-on base stations in multiple licensed systems operating in the 470-512 MHz, 769-775 MHz band,...

  8. 47 CFR 90.175 - Frequency coordinator requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... contour of a proposed station would overlap the service contour of a station on a frequency formerly... add-on base stations in multiple licensed systems operating in the 470-512 MHz, 769-775 MHz band,...

  9. Determination of the Wavelength of u.h.f. TV Transmissions

    ERIC Educational Resources Information Center

    Gaskell, D. C.

    1973-01-01

    Describes an experiment suitable for high school physics classes in which students determine the wavelength of electromagnetic radiation of u.h.f. television transmissions. Elaborate equipment is not required, and details are given for the construction of a dipole. (JR)

  10. 47 CFR 90.175 - Frequency coordinator requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... contour of a proposed station would overlap the service contour of a station on a frequency formerly...) Applications for add-on base stations in multiple licensed systems operating in the 470-512 MHz, 769-775...

  11. Calibration System for SLC 476MHz to 2856MHz Multipliers

    SciTech Connect

    Akre, Ron; /SLAC

    2011-08-26

    The two mile long Main Drive Line (MDL) distributes 476MHz at each of the 31 sectors along its length. Each of the 31 sectors has a six times multiplier which drives the 2856MHz phase reference system for that sector. This system is used to set and maintain phase of the accelerator structures over time. During previous runs significant down time resulted from sector phasing which was required after multiplier replacement. A system was designed to calibrate the phase of the 476MHz input to the phase of the 2856MHz output of the multiplier units. This enabled multipliers to be replaced without rephasing sectors.

  12. Multi-MHz retinal OCT

    PubMed Central

    Klein, Thomas; Wieser, Wolfgang; Reznicek, Lukas; Neubauer, Aljoscha; Kampik, Anselm; Huber, Robert

    2013-01-01

    We analyze the benefits and problems of in vivo optical coherence tomography (OCT) imaging of the human retina at A-scan rates in excess of 1 MHz, using a 1050 nm Fourier-domain mode-locked (FDML) laser. Different scanning strategies enabled by MHz OCT line rates are investigated, and a simple multi-volume data processing approach is presented. In-vivo OCT of the human ocular fundus is performed at different axial scan rates of up to 6.7 MHz. High quality non-mydriatic retinal imaging over an ultra-wide field is achieved by a combination of several key improvements compared to previous setups. For the FDML laser, long coherence lengths and 72 nm wavelength tuning range are achieved using a chirped fiber Bragg grating in a laser cavity at 419.1 kHz fundamental tuning rate. Very large data sets can be acquired with sustained data transfer from the data acquisition card to host computer memory, enabling high-quality averaging of many frames and of multiple aligned data sets. Three imaging modes are investigated: Alignment and averaging of 24 data sets at 1.68 MHz axial line rate, ultra-dense transverse sampling at 3.35 MHz line rate, and dual-beam imaging with two laser spots on the retina at an effective line rate of 6.7 MHz. PMID:24156052

  13. 47 CFR 95.628 - MedRadio transmitters in the 413-419 MHz, 426-432 MHz, 438-444 MHz, and 451-457 MHz and 2360-2400...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-432 MHz, 438-444 MHz, and 451-457 MHz and 2360-2400 MHz bands. 95.628 Section 95.628 Telecommunication..., 438-444 MHz, and 451-457 MHz and 2360-2400 MHz bands. The following provisions apply to MedRadio transmitters operating in the 413-419 MHz, 426-432 MHz, 438-444 MHz, and 451-457 MHz bands as part of a...

  14. 47 CFR 95.628 - MedRadio transmitters in the 413-419 MHz, 426-432 MHz, 438-444 MHz, and 451-457 MHz and 2360-2400...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-432 MHz, 438-444 MHz, and 451-457 MHz and 2360-2400 MHz bands. 95.628 Section 95.628 Telecommunication..., 438-444 MHz, and 451-457 MHz and 2360-2400 MHz bands. The following provisions apply to MedRadio transmitters operating in the 413-419 MHz, 426-432 MHz, 438-444 MHz, and 451-457 MHz bands as part of a...

  15. 47 CFR 74.602 - Frequency assignment.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... stations (CARS) operating between 12,700 and 13,200 MHz. Auxiliary stations licensed to low power TV... with and must accept interference from current and future full-power UHF-TV stations, LPTV stations...-13.20 GHz is reserved for television pickup and CARS pickup stations inside a 50 km radius of the...

  16. 47 CFR 74.602 - Frequency assignment.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... stations (CARS) operating between 12,700 and 13,200 MHz. Auxiliary stations licensed to low power TV... with and must accept interference from current and future full-power UHF-TV stations, LPTV stations...-13.20 GHz is reserved for television pickup and CARS pickup stations inside a 50 km radius of the...

  17. 47 CFR 74.602 - Frequency assignment.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... stations (CARS) operating between 12,700 and 13,200 MHz. Auxiliary stations licensed to low power TV... with and must accept interference from current and future full-power UHF-TV stations, LPTV stations...-13.20 GHz is reserved for television pickup and CARS pickup stations inside a 50 km radius of the...

  18. 47 CFR 101.79 - Sunset provisions for licensees in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands. 101.79 Section 101.79 Telecommunication FEDERAL... licensees in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands. (a) FMS licensees will maintain primary status in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands unless and until an...

  19. 47 CFR 101.79 - Sunset provisions for licensees in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands. 101.79 Section 101.79 Telecommunication FEDERAL... licensees in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands. (a) FMS licensees will maintain primary status in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands unless and until an...

  20. 47 CFR 101.79 - Sunset provisions for licensees in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands. 101.79 Section 101.79 Telecommunication FEDERAL... licensees in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands. (a) FMS licensees will maintain primary status in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands unless and until an...

  1. 47 CFR 101.79 - Sunset provisions for licensees in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands. 101.79 Section 101.79 Telecommunication FEDERAL... licensees in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands. (a) FMS licensees will maintain primary status in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands unless and until an...

  2. 47 CFR 101.79 - Sunset provisions for licensees in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands. 101.79 Section 101.79 Telecommunication FEDERAL... licensees in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands. (a) FMS licensees will maintain primary status in the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands unless and until an...

  3. 805 MHz and 201 MHz RF cavity development for MUCOOL

    SciTech Connect

    DLi@lbl.gov

    2002-10-10

    A muon cooling channel calls for very high acceleratinggradient RF structures to restore the energy lost by muons in theabsorbers. The RF structures have to be operated in a strong magneticfield and thus the use of superconducting RF cavities is excluded. Toachieve a high shunt impedance while maintaining a large enough apertureto accommodate a large transverse emittance muon beam, the cavity designadopted is a pillbox-like geometry with thin Be foils to terminate theelectromagnetic field at the cavity iris. The possibility of using gridsof thin-walled metallic tubes for the termination is also being explored.Many of the RF-related issues for muon cooling channels are being studiedboth theoretically and experimentally using an 805 MHz cavity that has apillbox-like geometry with thin Be windows to terminate the cavityaperture. The design and performance of this cavity are reported here.High-power RF tests of the 805 MHz cavity are in progress at Lab G inFermilab. The cavity has exceeded its design gradient of 30 MV/m,reaching 34 MV/m without external magnetic field. No surface damage wasobserved at this gradient. The cavity is currently under conditioning atLab G with an external magnetic field of 2.5 T. We also present here a201 MHz cavity design for muoncooling channels. The proposed cavitydesign is also suitable for use in a proof-of-principle Muon IonizationCooling Experiment (MICE).

  4. Achievement of 1020MHz NMR.

    PubMed

    Hashi, Kenjiro; Ohki, Shinobu; Matsumoto, Shinji; Nishijima, Gen; Goto, Atsushi; Deguchi, Kenzo; Yamada, Kazuhiko; Noguchi, Takashi; Sakai, Shuji; Takahashi, Masato; Yanagisawa, Yoshinori; Iguchi, Seiya; Yamazaki, Toshio; Maeda, Hideaki; Tanaka, Ryoji; Nemoto, Takahiro; Suematsu, Hiroto; Miki, Takashi; Saito, Kazuyoshi; Shimizu, Tadashi

    2015-07-01

    We have successfully developed a 1020MHz (24.0T) NMR magnet, establishing the world's highest magnetic field in high resolution NMR superconducting magnets. The magnet is a series connection of LTS (low-Tc superconductors NbTi and Nb3Sn) outer coils and an HTS (high-Tc superconductor, Bi-2223) innermost coil, being operated at superfluid liquid helium temperature such as around 1.8K and in a driven-mode by an external DC power supply. The drift of the magnetic field was initially ±0.8ppm/10h without the (2)H lock operation; it was then stabilized to be less than 1ppb/10h by using an NMR internal lock operation. The full-width at half maximum of a (1)H spectrum taken for 1% CHCl3 in acetone-d6 was as low as 0.7Hz (0.7ppb), which was sufficient for solution NMR. On the contrary, the temporal field stability under the external lock operation for solid-state NMR was 170ppb/10h, sufficient for NMR measurements for quadrupolar nuclei such as (17)O; a (17)O NMR measurement for labeled tri-peptide clearly demonstrated the effect of high magnetic field on solid-state NMR spectra. PMID:25978708

  5. Differential Photometry at 1612 MHz

    NASA Astrophysics Data System (ADS)

    Lewis, B. Murray

    2009-01-01

    The 1612 MHz light curves of high latitude OH/IR stars have been observed for several years with the Arecibo 305m telescope, to derive the light-travel time diameter of their shells from the phase difference between their red and blue shifted peaks, and to look for secular evolution of their masers. However, direct intensity measurements are always limited by the extent to which the telescope's characteristics can be removed. These, in Arecibo's case, are subject to changes in the weight distribution about the structure over time, to the functioning of the vertical tie-down system, which can be interrupted by thunder storms, and by temperature-related zenith angle effects during daytime observations. Nevertheless, all of these limitations are neutralized when the ratio of the two peaks is used as the observed parameter. This form of differential photometry often results in clean light curves, though the ratio may still be perturbed by RFI, by interstellar scintillation, and more predictably by noise. The increased sensitivity of this observing mode readily detects (1) any differential evolution of the two masers, as well as (2) highlighting changes in masing gain between the two peaks around the pulsation cycle, that in turn are indicative of the operation of partially rather than fully saturated masers. In many of our light-curves there are abrupt changes in the ratio of the peak intensities at a constant pulsation phase. These are interpreted as being due to the onset of dust formation at that phase of the pulsation cycle, with a consequent abrupt change in the reprocessing of the stellar SED, and hence to an abrupt change in the maser pump. This is a feature of the Gray, Howe & Lewis (MN 364, 783 (2005)) maser model. Examples of these effects will be shown.

  6. The ionospheric refraction at 38 MHz.

    NASA Astrophysics Data System (ADS)

    Milogradov-Turin, J.

    The investigation of the observed shift of the North Polar Spur (NPS) at the 38 MHz survey of Milogradov-Turin and Smith (1973) in respect to the position of the NPS on the survey at 408 MHz convolved to the same resolution (Haslam and Salter 1977) has shown that there is no dependence of the NPS position on frequency and that the ionospheric refraction should be larger than believed.

  7. A 50 MHz System for GMRT

    NASA Astrophysics Data System (ADS)

    Udaya Shankar, N.; Dwarakanath, K. S.; Amiri, S.; Somashekar, R.; Girish, B. S.; Laus, W.; Nayak, A.

    2009-09-01

    This paper describes a 50~MHz system being developed for GMRT to provide imaging capability in the frequency range 30-90~MHz. Due to its larger collecting area and higher antenna efficiency, the low-frequency GMRT system will be several times more sensitive than the present 74~MHz VLA system and is likely to remain a competitive instrument in this frequency band. In the first phase of this project, receiver systems consisting of V-dipole feeds and front-ends have been installed on four of the thirty GMRT antennas. Test observations were carried out on a number of bright 3CR sources. The initial results are encouraging. This paper will also describe results of simultaneous observations carried out using the existing GMRT correlator, the new GMRT software correlator and a system employing digitization and direct recording of signals at two antenna bases.

  8. Nonthermal galactic emission below 10 MHz

    NASA Technical Reports Server (NTRS)

    Novaco, J. C.; Brown, L. W.

    1977-01-01

    The Radio Astronomy Explorer-2 (RAE-2) satellite has provided new measurements of the nonthermal galactic radio emission at frequencies below 10 MHz. Measurements of the emission spectra are presented for the center, anticenter, north polar, and south polar directions at 22 frequencies between 0.25 and 9.18 MHz. Survey maps of the spatial distribution of the observed low frequency galactic emission at 1.31, 2.20, 3.93, 4.70, 6.55, and 9.18 MHz are presented. The observations were obtained with the 229-meter traveling-wave V-antenna on this lunar orbiting spacecraft. The improved frequency coverage offers additional insights into structure of the local galactic neighborhood.

  9. 47 CFR 27.1102 - Designated Entities in the 1710-1755 MHz and 2110-2155 MHz bands.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 2110-2155 MHz bands. 27.1102 Section 27.1102 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz, 2110-2155... the 1710-1755 MHz and 2110-2155 MHz bands. (a) Eligibility for small business provisions. (1) A...

  10. BLAZAR SPECTRAL PROPERTIES AT 74 MHz

    SciTech Connect

    Massaro, F.; Funk, S.; Giroletti, M.; Paggi, A.; D'Abrusco, R.; Tosti, G.

    2013-10-01

    Blazars are the most extreme class of active galactic nuclei. Despite a previous investigation at 102 MHz for a small sample of BL Lac objects and our recent analysis of blazars detected in the Westerbork Northern Sky Survey, a systematic study of the blazar spectral properties at frequencies below 100 MHz has been never carried out. In this paper, we present the first analysis of the radio spectral behavior of blazars based on the recent Very Large Array Low-frequency Sky Survey (VLSS) at 74 MHz. We search for blazar counterparts in the VLSS catalog, confirming that they are detected at 74 MHz. We then show that blazars present radio-flat spectra (i.e., radio spectral indices of ∼0.5) when evaluated, which also about an order of magnitude in frequency lower than previous analyses. Finally, we discuss the implications of our findings in the context of the blazars-radio galaxies connection since the low-frequency radio data provide a new diagnostic tool to verify the expectations of the unification scenario for radio-loud active galaxies.

  11. 47 CFR 15.245 - Operation within the bands 902-928 MHz, 2435-2465 MHz, 5785-5815 MHz, 10500-10550 MHz, and 24075...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... limited to intentional radiators used as field disturbance sensors, excluding perimeter protection systems... field disturbance sensors operating in the 24075-24175 MHz band and for other field disturbance sensors... disturbance sensors, 7.5 mV/m. (iii) Field disturbance sensors designed to be used in motor vehicles...

  12. 47 CFR 15.245 - Operation within the bands 902-928 MHz, 2435-2465 MHz, 5785-5815 MHz, 10500-10550 MHz, and 24075...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... limited to intentional radiators used as field disturbance sensors, excluding perimeter protection systems... field disturbance sensors operating in the 24075-24175 MHz band and for other field disturbance sensors... disturbance sensors, 7.5 mV/m. (iii) Field disturbance sensors designed to be used in motor vehicles...

  13. 47 CFR 15.245 - Operation within the bands 902-928 MHz, 2435-2465 MHz, 5785-5815 MHz, 10500-10550 MHz, and 24075...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... limited to intentional radiators used as field disturbance sensors, excluding perimeter protection systems... field disturbance sensors operating in the 24075-24175 MHz band and for other field disturbance sensors... disturbance sensors, 7.5 mV/m. (iii) Field disturbance sensors designed to be used in motor vehicles...

  14. 47 CFR 15.245 - Operation within the bands 902-928 MHz, 2435-2465 MHz, 5785-5815 MHz, 10500-10550 MHz, and 24075...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... limited to intentional radiators used as field disturbance sensors, excluding perimeter protection systems... field disturbance sensors operating in the 24075-24175 MHz band and for other field disturbance sensors... disturbance sensors, 7.5 mV/m. (iii) Field disturbance sensors designed to be used in motor vehicles...

  15. 47 CFR 15.245 - Operation within the bands 902-928 MHz, 2435-2465 MHz, 5785-5815 MHz, 10500-10550 MHz, and 24075...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... limited to intentional radiators used as field disturbance sensors, excluding perimeter protection systems... field disturbance sensors operating in the 24075-24175 MHz band and for other field disturbance sensors... disturbance sensors, 7.5 mV/m. (iii) Field disturbance sensors designed to be used in motor vehicles...

  16. 47 CFR 27.501 - 746-763 MHz, 775-793 MHz, and 805-806 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false 746-763 MHz, 775-793 MHz, and 805-806 MHz bands subject to competitive bidding. 27.501 Section 27.501 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Competitive...

  17. 47 CFR 27.501 - 746-763 MHz, 775-793 MHz, and 805-806 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false 746-763 MHz, 775-793 MHz, and 805-806 MHz bands subject to competitive bidding. 27.501 Section 27.501 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Competitive...

  18. 47 CFR 27.501 - 746-758 MHz, 775-788 MHz, and 805-806 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false 746-758 MHz, 775-788 MHz, and 805-806 MHz bands subject to competitive bidding. 27.501 Section 27.501 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Competitive...

  19. 47 CFR 27.501 - 746-763 MHz, 775-793 MHz, and 805-806 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false 746-763 MHz, 775-793 MHz, and 805-806 MHz bands subject to competitive bidding. 27.501 Section 27.501 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Competitive...

  20. 47 CFR 27.501 - 746-763 MHz, 775-793 MHz, and 805-806 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false 746-763 MHz, 775-793 MHz, and 805-806 MHz bands subject to competitive bidding. 27.501 Section 27.501 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Competitive...

  1. 47 CFR 15.231 - Periodic operation in the band 40.66-40.70 MHz and above 70 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Periodic operation in the band 40.66-40.70 MHz... Periodic operation in the band 40.66-40.70 MHz and above 70 MHz. (a) The provisions of this section are restricted to periodic operation within the band 40.66-40.70 MHz and above 70 MHz. Except as shown...

  2. 47 CFR 90.317 - Fixed ancillary signaling and data transmissions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Fixed ancillary signaling and data transmissions. 90.317 Section 90.317 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz...

  3. 47 CFR 90.317 - Fixed ancillary signaling and data transmissions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Fixed ancillary signaling and data transmissions. 90.317 Section 90.317 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz...

  4. 47 CFR 90.317 - Fixed ancillary signaling and data transmissions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Fixed ancillary signaling and data transmissions. 90.317 Section 90.317 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz...

  5. 47 CFR 90.317 - Fixed ancillary signaling and data transmissions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Fixed ancillary signaling and data transmissions. 90.317 Section 90.317 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz...

  6. 47 CFR 90.317 - Fixed ancillary signaling and data transmissions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Fixed ancillary signaling and data transmissions. 90.317 Section 90.317 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz...

  7. The NATO III 5 MHz Distribution System

    NASA Technical Reports Server (NTRS)

    Vulcan, A.; Bloch, M.

    1981-01-01

    A high performance 5 MHz distribution system is described which has extremely low phase noise and jitter characteristics and provides multiple buffered outputs. The system is completely redundant with automatic switchover and is self-testing. Since the 5 MHz reference signals distributed by the NATO III distribution system are used for up-conversion and multiplicative functions, a high degree of phase stability and isolation between outputs is necessary. Unique circuit design and packaging concepts insure that the isolation between outputs is sufficient to quarantee a phase perturbation of less than 0.0016 deg when other outputs are open circuited, short circuited or terminated in 50 ohms. Circuit design techniques include high isolation cascode amplifiers. Negative feedback stabilizes system gain and minimizes circuit phase noise contributions. Balanced lines, in lieu of single ended coaxial transmission media, minimize pickup.

  8. 76 FR 11681 - Improving Public Safety Communications in the 800 MHz Band; New 800 MHz Band Plan for Puerto Rico...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-03

    ... systems operating in the band, 69 FR 67823, November 22, 2004. In a Third Report and Order and Third..., USVI incumbents in the 806-809/851-854 MHz band segment will be relocated to comparable spectrum in the... COMMISSION 47 CFR Part 90 Improving Public Safety Communications in the 800 MHz Band; New 800 MHz Band...

  9. 47 CFR 27.1102 - Designated Entities in the 1710-1755 MHz and 2110-2155 MHz bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Designated Entities in the 1710-1755 MHz and 2110-2155 MHz bands. 27.1102 Section 27.1102 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz,...

  10. 47 CFR 27.1002 - Designated entities in the 1915-1920 MHz and 1995-2000 MHz bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Designated entities in the 1915-1920 MHz and 1995-2000 MHz bands. 27.1002 Section 27.1002 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1915-1920 MHz and...

  11. 47 CFR 27.1102 - Designated Entities in the 1710-1755 MHz and 2110-2155 MHz bands.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Designated Entities in the 1710-1755 MHz and 2110-2155 MHz bands. 27.1102 Section 27.1102 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz,...

  12. 47 CFR 27.1102 - Designated Entities in the 1710-1755 MHz and 2110-2155 MHz bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Designated Entities in the 1710-1755 MHz and 2110-2155 MHz bands. 27.1102 Section 27.1102 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1695-1710 MHz,...

  13. 47 CFR 27.1002 - Designated entities in the 1915-1920 MHz and 1995-2000 MHz bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Designated entities in the 1915-1920 MHz and 1995-2000 MHz bands. 27.1002 Section 27.1002 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1915-1920 MHz and...

  14. 47 CFR 27.1102 - Designated Entities in the 1710-1755 MHz and 2110-2155 MHz bands.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Designated Entities in the 1710-1755 MHz and 2110-2155 MHz bands. 27.1102 Section 27.1102 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz,...

  15. 47 CFR 27.1104 - Designated Entities in the 2000-2020 MHz and 2180-2200 MHz bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Designated Entities in the 2000-2020 MHz and 2180-2200 MHz bands. 27.1104 Section 27.1104 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz,...

  16. Miniaturized bendable 400 MHz artificial magnetic conductor

    NASA Astrophysics Data System (ADS)

    Presse, Anthony; Tarot, Anne-Claude

    2016-04-01

    A bendable artificial magnetic conductor (AMC) with a resonant frequency of 400 MHz is proposed. The dimensions of the unit cell are 50 × 50 mm2 or 0.07 × 0.07 λ0. The miniaturization is achieved with closely coupled patches printed on each side of a 0.127-mm-thick dielectric substrate. This last one is stacked on a flexible 3-mm-thick silicone over a ground plane. An AMC prototype is simulated and manufactured. Also, a printed inverted-F antenna is used to highlight the bandwidth of the AMC.

  17. Superconducting 112 MHz QWR electron gun

    SciTech Connect

    Belomestnykh, S.; Ben-Zvi, I.; Boulware, C.H.; Chang, X.; Grimm, T.L.; Rao, T.; Siegel, B.; Skaritka, J.; Than, R.; Winowski, M.; Wu, Q.; Xin, T.; Xue, L.

    2011-07-25

    Brookhaven National Laboratory and Niowave, Inc. have designed and fabricated a superconducting 112 MHz quarter-wave resonator (QWR) electron gun. The first cold test of the QWR cryomodule has been completed at Niowave. The paper describes the cryomodule design, presents the cold test results, and outline plans to upgrade the cryomodule. Future experiments include studies of different photocathodes and use for the coherent electron cooling proof-of-principle experiment. Two cathode stalk options, one for multi-alkali photocathodes and the other one for a diamond-amplified photocathode, are discussed. A quarter-wave resonator concept of superconducting RF (SRF) electron gun was proposed at BNL for electron cooling hadron beams in RHIC. QWRs can be made sufficiently compact even at low RF frequencies (long wavelengths). The long wavelength allows to produce long electron bunches, thus minimizing space charge effects and enabling high bunch charge. Also, such guns should be suitable for experiments requiring high average current electron beams. A 112 MHz QWR gun was designed, fabricated, and cold-tested in collaboration between BNL and Niowave. This is the lowest frequency SRF gun ever tested successfully. In this paper we describe the gun design and fabrication, present the cold test results, and outline our plans. This gun will also serve as a prototype for a future SRF gun to be used for coherent electron cooling of hadrons in eRHIC.

  18. A Four Channel 250 MHz Visual Counter

    SciTech Connect

    Flores, I.; Blando, P.; Crawford, H.; Engelage, J.; Greiner, L.; Ko, S.; Krebs, G.; Visser, G.

    1992-04-01

    A visual counter rated at 250 mhz. with a pulse-pair resolution of 2.6 nanoseconds for nuclear instrument module (NIM) signals has been designed. Pulse widths for NIM signals must be equal to or greater than 2 ns. The counter has a separate input for transistor-transistor logic (TTL) signals and for this logic level it operates at rates equal to or less than 190 mhz. TTL pulses must be greater than 4 ns. The design was implemented on a printed circuit card. Four of these cards were packaged into a single unit resulting in a four channel device that can be mounted into a 19 inch rack. Seven units were built; they are presently used in the experimental area and in the Main Control Room of the Bevalac. The counter accepts well defined NIM or TTL signals internally terminated with 50 ohms. All the controls and the signal input connectors are located on the front panel. An Overflow output, Gate, and Reset inputs are located on the back panel. The counters have 8 Light Emitting Diode digit displays which are 20.3 mm high with a viewing distance rating of 10 meters. Light filters are used for the LED displays greatly enhancing their visibility.

  19. TEM Cell Testing of Cable Noise Reduction Techniques from 2 MHz to 200 MHz -- Part 2

    NASA Technical Reports Server (NTRS)

    Bradley, Arthur T.; Evans, William C.; Reed, Joshua L.; Shimp, Samuel K., III; Fitzpatrick, Fred D.

    2008-01-01

    This paper presents empirical results of cable noise reduction techniques as demonstrated in a TEM cell operating with radiated fields from 2 - 200 MHz. It is the second part of a two-paper series. The first paper discussed cable types and shield connections. In this second paper, the effects of load and source resistances and chassis connections are examined. For each topic, well established theories are compared to data from a real-world physical system. Finally, recommendations for minimizing cable susceptibility (and thus cable emissions) are presented. There are numerous papers and textbooks that present theoretical analyses of cable noise reduction techniques. However, empirical data is often targeted to low frequencies (e.g. <50 KHz) or high frequencies (>100 MHz). Additionally, a comprehensive study showing the relative effects of various noise reduction techniques is needed. These include the use of dedicated return wires, twisted wiring, cable shielding, shield connections, changing load or source impedances, and implementing load- or source-to-chassis isolation. We have created an experimental setup that emulates a real-world electrical system, while still allowing us to independently vary a host of parameters. The goal of the experiment was to determine the relative effectiveness of various noise reduction techniques when the cable is in the presence of radiated emissions from 2 MHz to 200 MHz.

  20. BNL 703 MHz SRF cryomodule demonstration

    SciTech Connect

    Burrill,A.; Ben-Zvi, I.; Calaga, R.; Dalesio, L.; Dottavio, T.; Gassner, D.; Hahn, H.; Hoff, L.; Kayran, D.; Kewisch, J.; Lambiase, R.; Lederle, d.; Litvinenko, v.; Mahler, G.; McIntyre, G.; et al.

    2009-05-04

    This paper will present the preliminary results of the testing of the 703 MHz SRF cryomodule designed for use in the ampere class ERL under construction at Brookhaven National Laboratory. The preliminary cavity tests, carried out at Thomas Jefferson Laboratory, demonstrated cavity performance of 20 MV/m with a Qo of 1 x 10{sup 10}, results we expect to reproduce in the horizontal configuration. This test of the entire string assembly will allow us to evaluate all of the additional cryomodule components not previously tested in the VTA and will prepare us for our next milestone test which will be delivery of electrons from our injector through the cryomodule to the beam dump. This will also be the first demonstration of an accelerating cavity designed for use in an ampere class ERL, a key development which holds great promise for future machines.

  1. Compact Miniaturized Antenna for 210 MHz RFID

    NASA Technical Reports Server (NTRS)

    Lee, Richard Q.; Chun, Kue

    2008-01-01

    This paper describes the design and simulation of a miniaturized square-ring antenna. The miniaturized antenna, with overall dimensions of approximately one tenth of a wavelength (0.1 ), was designed to operate at around 210 MHz, and was intended for radio-frequency identification (RFID) application. One unique feature of the design is the use of a parasitic element to improve the performance and impedance matching of the antenna. The use of parasitic elements to enhance the gain and bandwidth of patch antennas has been demonstrated and reported in the literature, but such use has never been applied to miniaturized antennas. In this work, we will present simulation results and discuss design parameters and their impact on the antenna performance.

  2. Shift Register Clock Rate Effects on Coincidence Collection 50MHz versus 4MHz Comparison Tests

    SciTech Connect

    Newell, Matthew R.; Bourret, Steven C.; Swinhoe, Martyn Thomas

    2015-11-03

    The following report identifies and quantifies the timing differences between the older slower Shift Register Coincidence/Multiplicity modules and today’s modern higher speed devices. Modern high speed Shift Register Coincidence/Multiplicity instruments employ high speed internal clocks that run at frequencies more than ten times the older units, typically 50MHz. These higher speed clocks allow for a finer time resolution when recording input pulses.

  3. 47 CFR 90.259 - Assignment and use of frequencies in the bands 216-220 MHz and 1427-1432 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... performed in the 1427-1429 MHz and 1431.5-1432 MHz bands. The maximum ERP limitations are as follows...) For all other locations, primary operations are performed in the 1429.5-1432 MHz band. The maximum...

  4. Simultaneous Observations of Giant Pulses from Pulsar PSR B0950+08 at 42 MHz and 74 MHz

    NASA Astrophysics Data System (ADS)

    Tsai, -Wei, Jr.; Simonetti, John H.; Akukwe, Bernadine; Bear, Brandon; Gough, Jonathan D.; Shawhan, Peter; Kavic, Michael

    2016-02-01

    We report the detection of giant pulse (GP) emission from PSR B0950+08 in 12 hr of observations made simultaneously at 42 and 74 MHz, using the first station of the Long Wavelength Array. We detected 275 GPs (in 0.16% of the pulse periods) and 465 GPs (0.27%) at 42 and 74 MHz, respectively. The pulsar is weaker and produces less frequent GPs than at 100 MHz. Here, GPs are taken as having ≥slant 10 times the flux density of an average pulse (AP); their cumulative distribution of pulse strength follows a power law, with an index of -4.1 at 42 MHz and -5.1 at 74 MHz, which is much less steep than would be expected if we were observing the tail of a Gaussian distribution of normal pulses. We detected no other transient pulses in a wide dispersion measure range from 1 to 5000 pc cm-3. There were 128 GPs detected within the same periods from both 42 and 74 MHz, which means more than half of them are not generated in a wide band. The CLEAN-based algorithm was used to deconvolve the the effect of scattering broadening and we have concluded that the scattering effect from the interstellar medium at 42 and 74 MHz is weak and cannot be distinguished from the pulse profiles. We calculated the altitude r of the emission region using the dipolar magnetic field model. We found r(42 MHz) = 29.27 km (0.242% of RLC) and r(74 MHz) = 29.01 km (0.240% of RLC) for the AP, while for GPs, r(42 MHz) = 29.10 km (0.241% of RLC) and r(74 MHz) = 28.95 km (0.240% of RLC). GPs, which have a double-peak structure, have a smaller mean peak-to-peak separation compared to the AP.

  5. 47 CFR 27.17 - Discontinuance of service in the 2000-2020 MHz and 2180-2200 MHz bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Discontinuance of service in the 2000-2020 MHz and 2180-2200 MHz bands. 27.17 Section 27.17 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Applications and...

  6. 75 FR 56533 - Wireless Telecommunications Bureau Postpones Auction of 218-219 MHz Service and Phase II 220 MHz...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-16

    ... COMMISSION Wireless Telecommunications Bureau Postpones Auction of 218-219 MHz Service and Phase II 220 MHz... document announces the postponement of Auction 89. FOR FURTHER INFORMATION CONTACT: Wireless... related documents are also available on the Internet at the Commission's Web site:...

  7. Imaging melanin cancer growth in-vivo using raster-scan optoacoustic mesoscopy (RSOM) at 50 MHz and 100 MHz

    NASA Astrophysics Data System (ADS)

    Omar, Murad; Schwarz, Mathias; Soliman, Dominik; Symvoulidis, Panagiotis; Ntziachristos, Vasilis

    2016-03-01

    We used raster-scan optoacoustic mesoscopy (RSOM) at 50 MHz, and at 100 MHz, to monitor tumor growth, and tumor angiogenesis, which is a central hallmark of cancer, in-vivo. In this study we compared the performance, and the effect of the 50 MHz, and the 100 MHz frequencies on the quality of the final image. The system is based on a reflection-mode implementation of RSOM. The detectors used are custom made, ultrawideband, and spherically focused. The use of such detectors enables light coupling from the same side as the detector, thus reflection-mode. Light is in turn coupled using a fiber bundle, and the detector is raster scanned in the xy-plane. Subsequently, to retrieve small features, the raw data are reconstructed using a multi-bandwidth, beamforming reconstruction algorithm. Comparison of the system performance at the different frequencies shows as expected a higher resolution in case of the 100 MHz detector compared to the 50 MHz. On the other hand the 50 MHz has a better SNR, can detect features from deeper layers, and has higher angular acceptance. Based on these characteristics the 50 MHz detector was mostly used. After comparing the performance we monitored the growth of B16F10 cells, melanin tumor, over the course of 9 days. We see correspondence between the optoacoustic measurements and the cryoslice validations. Additionally, in areas close to the tumor we see sprouting of new vessels, starting at day 4-5, which corresponds to tumor angiogenesis.

  8. TEM Cell Testing of Cable Noise Reduction Techniques From 2 MHz to 200 MHz - Part 1

    NASA Technical Reports Server (NTRS)

    Bradley, Arthur T.; Evans, William C.; Reed, Joshua L.; Shimp, Samuel K.; Fitzpatrick, Fred D.

    2008-01-01

    This paper presents empirical results of cable noise reduction techniques as demonstrated in a TEM cell operating with radiated fields from 2 - 200 MHz. It is the first part of a two-paper series. This first paper discusses cable types and shield connections. In the second paper, the effects of load and source resistances and chassis connections are examined. For each topic, well established theories are compared to data from a real-world physical system. Finally, recommendations for minimizing cable susceptibility (and thus cable emissions) are presented. There are numerous papers and textbooks that present theoretical analyses of cable noise reduction techniques. However, empirical data is often targeted to low frequencies (e.g. <50 KHz) or high frequencies (>100 MHz). Additionally, a comprehensive study showing the relative effects of various noise reduction techniques is needed. These include the use of dedicated return wires, twisted wiring, cable shielding, shield connections, changing load or source impedances, and implementing load- or source-to-chassis isolation. We have created an experimental setup that emulates a real-world electrical system, while still allowing us to independently vary a host of parameters. The goal of the experiment was to determine the relative effectiveness of various noise reduction techniques when the cable is in the presence of radiated emissions from 2 MHz to 200 MHz. The electronic system (Fig. 1) consisted of two Hammond shielded electrical enclosures, one containing the source resistance, and the other containing the load resistance. The boxes were mounted on a large aluminium plate acting as the chassis. Cables connecting the two boxes measured 81 cm in length and were attached to the boxes using standard D38999 military-style connectors. The test setup is shown in Fig. 2. Electromagnetic fields were created using an HP8657B signal generator, MiniCircuits ZHL-42W-SMA amplifier, and an EMCO 5103 TEM cell. Measurements were

  9. Design concepts and performance of NASA X-band (7162 MHz/8415 MHz) transponder for deep-space spacecraft applications

    NASA Technical Reports Server (NTRS)

    Mysoor, N. R.; Perret, J. D.; Kermode, A. W.

    1991-01-01

    The design concepts and measured performance characteristics are summarized of an X band (7162 MHz/8415 MHz) breadboard deep space transponder (DSP) for future spacecraft applications, with the first use scheduled for the Comet Rendezvous Asteroid Flyby (CRAF) and Cassini missions in 1995 and 1996, respectively. The DST consists of a double conversion, superheterodyne, automatic phase tracking receiver, and an X band (8415 MHz) exciter to drive redundant downlink power amplifiers. The receiver acquires and coherently phase tracks the modulated or unmodulated X band (7162 MHz) uplink carrier signal. The exciter phase modulates the X band (8415 MHz) downlink signal with composite telemetry and ranging signals. The receiver measured tracking threshold, automatic gain control, static phase error, and phase jitter characteristics of the breadboard DST are in good agreement with the expected performance. The measured results show a receiver tracking threshold of -158 dBm and a dynamic signal range of 88 dB.

  10. Investigation of radio astronomical windows between 1 MHz and 2060 MHz in Universiti Malaya, Malaysia

    NASA Astrophysics Data System (ADS)

    Abidin, Zamri Zainal; Ibrahim, Zainol Abidin; Adnan, Syed Bahari Ramadzan Syed; Anuar, Norwati Khairul

    2009-08-01

    An indoor and an outdoor radio frequency survey was conducted in Universiti Malaya, Malaysia, as a test site, for the purpose of developing radio astronomy research in Malaysia. This is the first radio astronomical survey of any such done in Malaysia. Observation and analysis were done in the radio frequency spectrum between 1 MHz and 2060 MHz. In this paper, the experimental setup and procedure of surveying are outlined and the measured data are interpreted. The eight radio astronomical windows were investigated from a 24 h observation, with the emphasis on two of the most important radio astronomical windows which are protected by the Malaysian Communications and Multimedia Commission (MCMC). Some intermittent observations were also done for referencing purposes. The radio frequency interferences (RFIs) are found to be relatively low. The overall relative Interference-to-Noise ratio (INR) at this test site ranges between 5.72% and 11.74%. The average strength of RFI in the eight focused radio astronomical windows at this site ranges between -100 dBm and -90 dBm (equivalently between 9.23 × 10 4 Jy and 93.29 × 10 4 Jy at resolution bandwidth of 125 kHz).

  11. An inexpensive 15 MHz fiber optic analog data link

    NASA Astrophysics Data System (ADS)

    Lagerstroem, E.; Kindberg, G.; Haegerstroem, G.; Drake, J. R.

    1982-03-01

    Circuit diagrams for the transmitter and receiver for an analog data link are presented. Analog signals are transmitted over distances of several meters via a fiber optic cable. System bandwidth is 10 to 15 MHz with a gain of unity for amplitudes of + or - 0.5 V. Transmission is switched to dc if moderate drift is acceptable. The signal to noise ratio is 46 dB which can be improved if a 5 MHz filter is used with transient recorders with a 20 MHz digitizing rate. A surge arrester protects against very fast high amplitude voltage spikes.

  12. The 121.75 MHz band pass filter

    NASA Technical Reports Server (NTRS)

    Davis, R. J.

    1975-01-01

    Prior to the ASTP joint flight it was observed during various tests on the USA's VHF/FM system, that the 121.75 MHz receiver unsquelched when exposed to certain RF power levels at a frequency of 142.417 MHz. Tests were conducted in an effort to arrive at a solution. Several recommendations were made but the most feasible was to insert a selective band pass filter in the transmit/receiver line of the VHF/FM transceiver. The tests were performed on the filter to determine the frequency response and rejection capabilities at 142.417 MHz.

  13. Hunting for MHz gravitational waves with the Fermilab Holometer

    NASA Astrophysics Data System (ADS)

    Kamai, Brittany; The Holometer Collaboration Collaboration

    2016-03-01

    The highest frequency end of the gravitational wave spectrum remains poorly constrained. Cosmic strings and primordial black holes are potential gravitational waves candidates that could radiate at MHz frequencies. The existence of nearby sources can be tested using the Fermilab Holometer, two nested 40 meter Michelson interferometers. This instrument can achieve strain sensitivity better than 10- 20 / rt .Hz within the 1-10 MHz frequency band. The Holometer is fully operational and has taken long observational campaigns acquiring 100s of hours of science quality data. I will present results of a search for narrow-lined sources and constraints on the stochastic background in the MHz band.

  14. 47 CFR 27.1176 - Cost-sharing requirements for AWS in the 2150-2160/62 MHz band.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... clearance of BRS incumbents from this spectrum, including BRS incumbents occupying the 2150-2162 MHz band on...-2160/62 MHz band. 27.1176 Section 27.1176 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... MHz, 1755-1780 MHz, 2110-2155 MHz, 2155-2180 MHz, 2180-2200 MHz Bands Cost-Sharing Policies...

  15. Achievement of a 920-MHz High Resolution NMR

    NASA Astrophysics Data System (ADS)

    Hashi, Kenjiro; Shimizu, Tadashi; Goto, Atsushi; Kiyoshi, Tsukasa; Matsumoto, Shinji; Wada, Hitoshi; Fujito, Teruaki; Hasegawa, Ken-ichi; Yoshikawa, Masatoshi; Miki, Takashi; Ito, Satoshi; Hamada, Mamoru; Hayashi, Seiji

    2002-06-01

    We have developed a 920-MHz NMR system and performed the proton NMR measurement of H 2O and ethylbenzene using the superconducting magnet operating at 21.6 T (920 MHz for proton), which is the highest field produced by a superconducting NMR magnet in the persistent mode. From the NMR measurements, it is verified that both homogeneity and stability of the magnet have a specification sufficient for a high resolution NMR.

  16. Real-Time, Polyphase-FFT, 640-MHz Spectrum Analyzer

    NASA Technical Reports Server (NTRS)

    Zimmerman, George A.; Garyantes, Michael F.; Grimm, Michael J.; Charny, Bentsian; Brown, Randy D.; Wilck, Helmut C.

    1994-01-01

    Real-time polyphase-fast-Fourier-transform, polyphase-FFT, spectrum analyzer designed to aid in detection of multigigahertz radio signals in two 320-MHz-wide polarization channels. Spectrum analyzer divides total spectrum of 640 MHz into 33,554,432 frequency channels of about 20 Hz each. Size and cost of polyphase-coefficient memory substantially reduced and much of processing loss of windowed FFTs eliminated.

  17. Study of loss mechanisms of Mn-Zn ferrites in the frequency from 1 MHz to 10 MHz

    SciTech Connect

    Tung, M.J.; Tseng, T.Y. . Institute of Electronics); Chang, W.C. . Dept. of Physics); Liu, C.S.; Liu, T.Y.; Chen, C.J. . Materials Research Labs.)

    1993-11-01

    The core loss mechanism of low loss grade Mn-Zn ferrite in the frequency from 1MHz to 10MHz was investigated in order to find out the Possibility of developing Mn-Zn ferrites to be used at such high frequency region. under the condition of f.B = 25KHz.T, it was found that dielectric loss dominated the core loss at the frequency between 1.1 and 3MHz, while eddy current loss dominated the core loss at the frequency higher than 3MHz. It is suggested that decrease of grain boundary capacitance and increase of grain resistivity of the core may be the suitable ways for the Mn-Zn ferrites to be used at such frequency region.

  18. 47 CFR 27.1103 - 2000-2020 MHz and 2180-2200 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz, 2110-2155... competitive bidding procedures set forth in 47 CFR part 1, subpart Q will apply unless otherwise provided...

  19. 47 CFR 27.1101 - 1710-1755 MHz and 2110-2155 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz, 2110-2155... competitive bidding procedures set forth in 47 CFR part 1, subpart Q will apply unless otherwise provided...

  20. 47 CFR 27.1101 - 1710-1755 MHz and 2110-2155 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz, 2110-2155... bidding procedures set forth in 47 CFR part 1, subpart Q will apply unless otherwise provided in...

  1. 47 CFR 27.1001 - 1915-1920 MHz and 1995-2000 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1915-1920 MHz and 1995... forth in 47 CFR part 1, subpart Q will apply unless otherwise provided in this subpart....

  2. 47 CFR 27.1001 - 1915-1920 MHz and 1995-2000 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1915-1920 MHz and 1995... forth in 47 CFR part 1, subpart Q will apply unless otherwise provided in this subpart....

  3. 47 CFR 27.1101 - 1710-1755 MHz and 2110-2155 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz, 2110-2155... bidding procedures set forth in 47 CFR part 1, subpart Q will apply unless otherwise provided in...

  4. 47 CFR 27.1101 - 1710-1755 MHz and 2110-2155 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1695-1710 MHz, 1710-1755... competitive bidding. The general competitive bidding procedures set forth in 47 CFR part 1, subpart Q...

  5. 47 CFR 27.1101 - 1710-1755 MHz and 2110-2155 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz, 2110-2155... bidding procedures set forth in 47 CFR part 1, subpart Q will apply unless otherwise provided in...

  6. The 136 MHz/400 MHz earth station antenna-noise temperature prediction program documentation for RAE-B

    NASA Technical Reports Server (NTRS)

    Chin, M.

    1972-01-01

    A simulation study to determine the 136 MHz and 400 MHz noise temperature of the ground network antennas which will track the RAE-B satellite during data transmission periods is described. Since the noise temperature of the antenna effectively sets the signal-to-noise ratio (SNR) of the received signal, a knowledge of SNR will be helpful in locating the optimum time windows for data transmission during low-noise periods. Antenna-noise temperatures at 136 MHz and 400 MHz will be predicted for selected earth-based ground stations which will support RAE-B. The antenna-noise temperature predictions will include the effects of galactic-brightness temperature, the sun, and the brightest radio stars. Predictions will cover the ten-month period from March 1, 1973 to December 31, 1973. The RAE-B mission will be expecially susceptible to SNR degradation during the two eclipses of the Sun occurring in this period.

  7. 47 CFR 101.69 - Transition of the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands from the fixed microwave...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., and 2160-2200 MHz bands from the fixed microwave services to personal communications services and emerging technologies. 101.69 Section 101.69 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... been allocated for use by emerging technology (ET) services, including Personal Communications...

  8. 47 CFR 101.69 - Transition of the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands from the fixed microwave...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., and 2160-2200 MHz bands from the fixed microwave services to personal communications services and emerging technologies. 101.69 Section 101.69 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... been allocated for use by emerging technology (ET) services, including Personal Communications...

  9. 47 CFR 101.69 - Transition of the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands from the fixed microwave...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., and 2160-2200 MHz bands from the fixed microwave services to personal communications services and emerging technologies. 101.69 Section 101.69 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... been allocated for use by emerging technology (ET) services, including Personal Communications...

  10. 47 CFR 101.69 - Transition of the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands from the fixed microwave...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., and 2160-2200 MHz bands from the fixed microwave services to personal communications services and emerging technologies. 101.69 Section 101.69 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... been allocated for use by emerging technology (ET) services, including Personal Communications...

  11. 47 CFR 101.69 - Transition of the 1850-1990 MHz, 2110-2150 MHz, and 2160-2200 MHz bands from the fixed microwave...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., and 2160-2200 MHz bands from the fixed microwave services to personal communications services and emerging technologies. 101.69 Section 101.69 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... been allocated for use by emerging technology (ET) services, including Personal Communications...

  12. 120 MW, 800 MHz Magnicon for a Future Muon Collider

    SciTech Connect

    Jay L. Hirshfield

    2005-12-15

    Development of a pulsed magnicon at 800 MHz was carried out for the muon collider application, based on experience with similar amplifiers in the frequency range between 915 MHz and 34.3 GHz. Numerical simulations using proven computer codes were employed for the conceptual design, while established design technologies were incorporated into the engineering design. A cohesive design for the 800 MHz magnicon amplifier was carried out, including design of a 200 MW diode electron gun, design of the magnet system, optimization of beam dynamics including space charge effects in the transient and steady-state regimes, design of the drive, gain, and output cavities including an rf choke in the beam exit aperture, analysis of parasitic oscillations and design means to eliminate them, and design of the beam collector capable of 20 kW average power operation.

  13. Millisecond solar radio spikes observed at 1420 MHz

    NASA Astrophysics Data System (ADS)

    Dabrowski, B. P.; Kus, A. J.

    We present results from observations of narrowband solar millisecond radio spikes at 1420 MHz. Observing data were collected between February 2000 and December 2001 with the 15-m radio telescope at the Centre for Astronomy Nicolaus Copernicus University in Torun, Poland, equipped with a radio spectrograph that covered the 1352-1490 MHz frequency band. The radio spectrograph has 3 MHz frequency resolution and 80 microsecond time resolution. We analyzed the individual radio spike duration, bandwidth and rate of frequency drift. A part of the observed spikes showed well-outlined subtle structures. On dynamic radio spectrograms of the investigated events we notice complex structures formed by numerous individual spikes known as chains of spikes and distinctly different structure of columns. Positions of active regions connected with radio spikes emission were investigated. It turns out that most of them are located near the center of the solar disk, suggesting strong beaming of the spikes emission.

  14. 47 CFR 15.247 - Operation within the bands 902-928 MHz, 2400-2483.5 MHz, and 5725-5850 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... seconds within a 20 second period; if the 20 dB bandwidth of the hopping channel is 250 kHz or greater... frequency shall not be greater than 0.4 seconds within a 10 second period. The maximum allowed 20 dB... second period. (iii) Frequency hopping systems in the 2400-2483.5 MHz band shall use at least 15...

  15. Intravascular photoacoustic imaging at 35 and 80 MHz

    PubMed Central

    Li, Xiang; Wei, Wei; Shung, K. Kirk

    2012-01-01

    Abstract. The catheter-based intravascular photoacoustic (IVPA) imaging for diagnosing atherosclerosis, which can provide optical absorption contrast of the arterial wall besides acoustic scattering contrast from the conventional intravascular ultrasound (IVUS) imaging, has been intensively researched recently. The resolution of IVPA is determined by the frequency bandwidth of an ultrasonic transducer. Higher resolution can be achieved by increasing the transducer’s working frequency and bandwidth. We introduce IVPA imaging at 35 and 80 MHz by using newly designed integrated IVUS/IVPA probes. This is the first time IVPA has been achieved as high as 80 MHz. Six-micrometer tungsten wires were imaged to evaluate the probes’ spatial resolutions and beam patterns. Healthy rabbit aorta was imaged in vitro. Imaging results show that IVPA has superior contrast over IVUS in identifying the arterial wall, and IVPA at 80 MHz demonstrates extraordinary resolution (35 μm) compared to 35 MHz. PMID:23224004

  16. COSPAS/SARSAT 406-MHz emergency beacon digital controller

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.

    1988-01-01

    The digital control portion of a low-cost 406-MHz COSPAS/SARSAT emergency beacon has been designed and breadboarded at the NASA Lewis Research Center. This report discusses the requirements and design tradeoffs of the digital controller and describes the hardware and software design, which is available only to United States citizens and companies.

  17. Q disease on 350-MHZ superconducting spoke cavities

    SciTech Connect

    Tajima, T.; Edwards, R. L.; Krawczyk, F. L.; Liu, Jianfei; Schrage, D. L.; Shapiro, A. H.

    2003-01-01

    Q disease, i.e., an increase of RF surface resistance due to hydride precipitation, has been investigated with 350-MHz spoke cavities. This phenomenon was studied extensively in early 1990s with cavities at frequencies >1 GHz. This is possibly due to the fact that the lower-frequency cavities were believed to show insignificant effect. However, early 500-MHz KEK elliptical cavities and JAERI 130-MHz quarter wave resonators have shown significant Q degradation, suggesting that this disease can be a serious problem with lower-frequency cavities as well. Since there were no quantitative data with 350-MHz cavities, we decided to measure our two spoke cavities. Our spoke cavities were made of RRR{approx}250 niobium and were chemically polished {approx}150 microns. A few series of systematic tests have shown that our spoke cavities do not show any Q{sub 0} degradation up to {approx}24 hours of holding the cavity at 100 K. However it starts showing degradation if it is held for a longer time and the additional loss due to the Q disease increases linearly. It was also found that our spoke cavity recovers from Q disease if it is warmed up to 150 K or higher for 12 hours.

  18. Radar - 449MHz - Astoria, OR (AST) - Raw Data

    DOE Data Explorer

    Coleman, Tim

    2016-10-25

    **Winds.** A radar wind profiler measures the Doppler shift of electromagnetic energy scattered back from atmospheric turbulence and hydrometeors along 3-5 vertical and off-vertical point beam directions. Back-scattered signal strength and radial-component velocities are remotely sensed along all beam directions and are combined to derive the horizontal wind field over the radar. These data typically are sampled and averaged hourly and usually have 6-m and/or 100-m vertical resolutions up to 4 km for the 915 MHz and 8 km for the 449 MHz systems. **Temperature.** To measure atmospheric temperature, a radio acoustic sound system (RASS) is used in conjunction with the wind profile. These data typically are sampled and averaged for five minutes each hour and have a 60-m vertical resolution up to 1.5 km for the 915 MHz and 60-m up to 3.5k m for the 449 MHz. **Spectra.** The daily raw spectra data are available. The files are labeled "header" and "data." These data files are generated by LapXM, binary encoded, and are specific to this application. These datasets contain the raw data from the radar, such as signal-to-noise, signal power, radial velocity, and spectra widths.

  19. Radar - 449MHz - North Bend, OR (OTH) - Raw Data

    DOE Data Explorer

    Coleman, Tim

    2016-10-25

    **Winds.** A radar wind profiler measures the Doppler shift of electromagnetic energy scattered back from atmospheric turbulence and hydrometeors along 3-5 vertical and off-vertical point beam directions. Back-scattered signal strength and radial-component velocities are remotely sensed along all beam directions and are combined to derive the horizontal wind field over the radar. These data typically are sampled and averaged hourly and usually have 6-m and/or 100-m vertical resolutions up to 4 km for the 915 MHz and 8 km for the 449 MHz systems. **Temperature.** To measure atmospheric temperature, a radio acoustic sound system (RASS) is used in conjunction with the wind profile. These data typically are sampled and averaged for five minutes each hour and have a 60-m vertical resolution up to 1.5 km for the 915 MHz and 60-m up to 3.5k m for the 449 MHz. **Spectra.** The daily raw spectra data are available. The files are labeled "header" and "data." These data files are generated by LapXM, binary encoded, and are specific to this application. These datasets contain the raw data from the radar, such as signal-to-noise, signal power, radial velocity, and spectra widths.

  20. Radar - 449MHz - Forks, WA (FKS) - Raw Data

    DOE Data Explorer

    Coleman, Tim

    2016-10-25

    **Winds.** A radar wind profiler measures the Doppler shift of electromagnetic energy scattered back from atmospheric turbulence and hydrometeors along 3-5 vertical and off-vertical point beam directions. Back-scattered signal strength and radial-component velocities are remotely sensed along all beam directions and are combined to derive the horizontal wind field over the radar. These data typically are sampled and averaged hourly and usually have 6-m and/or 100-m vertical resolutions up to 4 km for the 915 MHz and 8 km for the 449 MHz systems. **Temperature.** To measure atmospheric temperature, a radio acoustic sound system (RASS) is used in conjunction with the wind profile. These data typically are sampled and averaged for five minutes each hour and have a 60-m vertical resolution up to 1.5 km for the 915 MHz and 60-m up to 3.5k m for the 449 MHz. **Spectra.** The daily raw spectra data are available. The files are labeled "header" and "data." These data files are generated by LapXM, binary encoded, and are specific to this application. These datasets contain the raw data from the radar, such as signal-to-noise, signal power, radial velocity, and spectra widths.

  1. High power testing of the 402.5 MHZ and 805 MHZ RF windows for the spallation neutron source accelerator

    SciTech Connect

    Cummings, K. A.; De Baca, J. M.; Harrison, J. S.; Rodriguez, M. B.; Torrez, P. A.; Warner, D. K.

    2003-01-01

    Hisorically, Radio Frequency (RF) windows have been a common point of failure in input power couplers; therefore, reliable RF windows are critical to the success of the Spallation Neutron Source (SNS) project. The normal conducting part of the SNS accelerator requires six RF windows at 402.5 MHz and eight RF windows at 805 MHz[l]. Each RF window will transmit up to 180 kW of average power and 2.5 MW peak power at 60 Hz with 1.2 millisecond pulses. The RF windows, designed and manufactured by Thales, were tested at the full average power for 4 hours to ensure no problems with the high average power and then tested to an effective forward power level of 10 MW by testing at 2.5 MW forward power into a short and varying the phase of the standing wave. The sliding short was moved from 0 to 180 degrees to ensure no arcing or breakdown problems occur in any part of the window. This paper discusses the results of the high power testing of both the 402.5 MHz and the 805 MHz RF windows. Problems encountered during testing and the solutions for these problems are discussed.

  2. 75 FR 35315 - Improving Public Safety Communications in the 800 MHz Band; New 800 MHz Band Plan for Puerto Rico...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-22

    ... public safety and other land mobile communication systems operating in the band, 69 FR 67823, November 22... Puerto Rico market compared to other markets, 72 FR 39756, July 20, 2007. Rather than specify a band plan... 800 MHz band reconfiguration in Puerto Rico as well as alternative band plans, 73 FR 40274, July...

  3. 800MHz Crab Cavity Conceptual Design For the LHC Upgrade

    SciTech Connect

    Xiao, Liling; Li, Zenghai; Ng, Cho-Kuen; Seryi, Andrei; /SLAC

    2009-05-26

    In this paper, we present an 800 MHz crab cavity conceptual design for the LHC upgrade. The cell shape is optimized for lower maximum peak surface fields as well as higher transverse R/Q. A compact coax-to-coax coupler scheme is proposed to damp the LOM/SOM modes. A two-stub antenna with a notch filter is used as the HOM coupler to damp the HOM modes in the horizontal plane and rejects the operating mode at 800MHz. Multipacting (MP) simulations show that there are strong MP particles at the disks. Adding grooves along the short axis without changing the operating mode's RF characteristics can suppress the MP activities. Possible input coupler configurations are discussed.

  4. R&D of BEPCII 500 MHz superconducting cavity

    NASA Astrophysics Data System (ADS)

    Liu, YaPing; Wang, GuangWei; Pan, WeiMin; Li, JiZhen; Liu, DeGui; Sun, Yi; Li, ZhongQuan; Dai, JianPing; Li, ShaoPeng; He, Kun; Wang, GuoPing; Zhao, GuangYuan; Ma, Qiang; Lin, HaiYing; Sha, Peng; Wang, QunYao; Qiu, Feng; Meng, FanBo; Li, Han

    2011-12-01

    Beijing Electron-Positron Collider Upgrade (BEPCII) adopts two 500 MHz superconducting cavities (SCCs) in each ring for higher accelerated gradient, higher Q and lower impedance (Wang et al. The proceedings of SRF'07). There's no spare cavity due to the limited time and funding during BEPCII construction. If any serious trouble happened on either one of the two cavities and could not be recovered in a short time, the operation of BEPCII facility will be affected. Therefore, since 2009 three spare cavities have been fabricated in China to ensure reliable operation, and two of them have been successfully vertically tested in January and July 2011. This paper will briefly present the manufacture, post-process and vertical test performance of the 500 MHz spare cavities.

  5. Fractal dimension of mesospheric radar backscatter at 2. 75 MHz

    SciTech Connect

    Hall, C.; Armstrong, R.J.; La Hoz, C. )

    1991-04-01

    The authors identified the fractal dimension of radar returns from the mesopause region at 2.75 MHz. The input dataset was a time series of echo amplitude at a discrete height obtained from a partial reflection radar operating at Ramfjordmoen in northern Norway. Two different algorithms both of which yield approximations to the fractal dimension have been employed and give almost identical results. The radar echo dataset in question exhibits a dimension of between 7 and 8.

  6. Fast Radio Transient searches with UTMOST at 843 MHz

    NASA Astrophysics Data System (ADS)

    Caleb, M.; Flynn, C.; Bailes, M.; Barr, E. D.; Bateman, T.; Bhandari, S.; Campbell-Wilson, D.; Green, A. J.; Hunstead, R. W.; Jameson, A.; Jankowski, F.; Keane, E. F.; Ravi, V.; van Straten, W.; Krishnan, V. Venkataraman

    2016-05-01

    We report the first radio interferometric search at 843 MHz for fast transients, particularly Fast Radio Bursts (FRBs). The recently recommissioned Swinburne University of Technology's digital backend for the Molonglo Observatory Synthesis Telescope array (the UTMOST) with its large collecting area (18 000 m2) and wide instantaneous field of view (7.80 deg2) is expected to be an efficient tool to detect FRBs. As an interferometer it will be capable of discerning whether the FRBs are truly a celestial population. We show that UTMOST at full design sensitivity can detect an event approximately every few days. We report on two preliminary FRB surveys at about 7 per cent and 14 per cent, respectively, of the array's final sensitivity. Several pulsars have been detected via single pulses and no FRBs were discovered with pulse widths (W), in the range 655.36 μs < W < 41.9 ms and dispersion measures (DMs) in the range 100 < DM < 2000 pc cm-3. This non-detection sets a 2σ upper limit of the sky rate of not more than 1000 events sky-1 d-1 at 843 MHz down to a flux limit of 11 Jy for 1 ms FRBs. We show that this limit is consistent with previous survey limits at 1.4 GHz and 145 MHz and set a lower limit on the mean spectral index of FRBs of α > -3.2.

  7. Design for a 1 MHz soft magnetic material hysteresisgraph (abstract)

    NASA Astrophysics Data System (ADS)

    Dennison, Eric

    1993-05-01

    Until recently, high frequency (1 MHz) testing of magnetically soft materials has been typically limited to measurement of core loss and peak or inductive ac permeability. A high frequency hysteresisgraph allows direct examination of the hysteresis loop and calculation of values for magnetic parameters such as coercivity (Hc), peak permeability (μp), remanence (Br), core loss (Pc,Pcv,Pcm), bias drive field strength (Hbias), maximum H drive (Hmax) and maximum or saturation induction (Bmax). This paper describes the methods used to construct and calibrate a commercial high frequency magnetic hysteresisgraph which is capable of recording the primary current and secondary voltage waveforms of magnetic cores driven at up to 1 MHz. A system accuracy of 2% (for B and H parameter values) and 5% (for core loss) was achieved through careful control and calibration of signal phase shifts within the circuitry. System calibration, magnetic field calculations, and use of FFT post-processing of the acquired waveforms are discussed. The ability to accurately record the hysteresis loop of a material at 1 MHz allows high frequency core materials to be characterized not only by core loss and permeability, but by their hysteresis loop shape, coercivity, and remanence, both under pure ac and dc biased ac drive conditions. Changes in material characteristics due to dc biasing, temperature variations, defects, or mechanical stresses can be readily observed and described in terms of changes to the hysteresis curve shape.

  8. A 2-to-48-MHz Phase-Locked Loop

    NASA Technical Reports Server (NTRS)

    Koudelka, Robert D.

    2004-01-01

    A 2-to-48-MHz phase-locked loop (PLL), developed for the U.S. space program, meets or exceeds all space shuttle clock electrical interface requirements by taking as its reference a 2-to-48-MHz clock signal and outputting a phaselocked clock signal set at the same frequency as the reference clock with transistor- transistor logic (TTL) voltage levels. Because it is more adaptable than other PLLs, the new PLL can be used in industries that employ signaling devices and as a tool in future space missions. A conventional PLL consists of a phase/frequency detector, loop filter, and voltage-controlled oscillator in which each component exists individually and is integrated into a single device. PLL components phase-lock to a single frequency or to a narrow bandwidth of frequencies. It is this design, however, that prohibits them from maintaining phase lock to a dynamically changing reference clock when a large bandwidth is required a deficiency the new PLL overcomes. Since most PLL components require their voltage-controlled oscillators to operate at greater than 2-MHz frequencies, conventional PLLs often cannot achieve the low-frequency phase lock allowed by the new PLL. The 2-to-48-MHz PLL is built on a wire-wrap board with pins wired to three position jumpers; this makes changing configurations easy. It responds to variations in voltage-controlled oscillator (VCO) ranges, duty cycle, signal-to-noise ratio (SNR), amplitude, and jitter, exceeding design specifications. A consensus state machine, implemented in a VCO range detector which assures the PLL continues to operate in the correct range, is the primary control state machine for the 2-to-48-MHz PLL circuit. By using seven overlapping frequency ranges with hysteresis, the PLL output sets the resulting phase-locked clock signal at a frequency that agrees with the reference clock with TTL voltage levels. As a space-shuttle tool, the new PLL circuit takes the noisy, degraded reference clock signals as input and outputs

  9. 47 CFR 27.1176 - Cost-sharing requirements for AWS in the 2150-2160/62 MHz band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-2160/62 MHz band. 27.1176 Section 27.1176 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... MHz, 2160-2180 MHz Bands Cost-Sharing Policies Governing Broadband Radio Service Relocation from the 2150-2160/62 Mhz Band § 27.1176 Cost-sharing requirements for AWS in the 2150-2160/62 MHz band....

  10. 47 CFR 27.1176 - Cost-sharing requirements for AWS in the 2150-2160/62 MHz band.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-2160/62 MHz band. 27.1176 Section 27.1176 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... MHz, 2160-2180 MHz Bands Cost-Sharing Policies Governing Broadband Radio Service Relocation from the 2150-2160/62 Mhz Band § 27.1176 Cost-sharing requirements for AWS in the 2150-2160/62 MHz band....

  11. 47 CFR 27.1176 - Cost-sharing requirements for AWS in the 2150-2160/62 MHz band.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... from this spectrum, including BRS incumbents occupying the 2150-2162 MHz band on a primary basis, must...-2160/62 MHz band. 27.1176 Section 27.1176 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... MHz, 2000-2020 MHz, and 2180-2200 MHz bands Cost-Sharing Policies Governing Broadband Radio...

  12. 47 CFR 27.1176 - Cost-sharing requirements for AWS in the 2150-2160/62 MHz band.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-2160/62 MHz band. 27.1176 Section 27.1176 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... MHz, 2160-2180 MHz Bands Cost-Sharing Policies Governing Broadband Radio Service Relocation from the 2150-2160/62 Mhz Band § 27.1176 Cost-sharing requirements for AWS in the 2150-2160/62 MHz band....

  13. 47 CFR 27.1300 - 600 MHz band subject to competitive bidding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... licenses are subject to competitive bidding. The general competitive bidding procedures set forth in 47 CFR... SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 600 MHz Band § 27.1300 600 MHz band subject...

  14. Effects of gas pressure on 60/13.56 MHz dual-frequency capacitively coupled plasmas

    SciTech Connect

    Yuan, Q. H.; Yin, G. Q.; Xin, Y.; Ning, Z. Y.

    2011-05-15

    The electron energy probability functions (EEPFs) were measured with increasing gas pressure in 60/13.56 MHz dual-frequency capacitively coupled plasma (DF-CCP) using compensated Langmiur electrostatic probe. The transition pressure of heating mode from collisionless to collisional heating in 60/13.56 MHz DF-CCP is found to be significantly lower than that in 13.56 MHz single-frequency CCP. As the pressure increases, the EEPFs change from bi-Maxwellian to Druyvesteyn type which is similar with that in 60 MHz single-frequency CCP. The pressure dependence of electron densities, effective electron temperatures, floating potentials, and plasma potentials in 60/13.56 MHz DF-CCP were measured and were compared with that in 60 MHz single-frequency CCP. The pressure dependence of these plasma parameters in 60/13.56 MHz DF-CCP is similar with that in 60 MHz single-frequency CCP.

  15. 47 CFR 87.199 - Special requirements for 406.0-406.1 MHz ELTs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... is incorporated by reference in accordance with 5 U.S.C. 552(a), and 1 CFR part 51. Copies of the...-406.1 MHz ELT must contain as an integral part a homing beacon operating only on 121.500 MHz that... (a) of this section. The 121.500 MHz homing beacon must have a continuous duty cycle that may...

  16. 47 CFR 90.901 - 800 MHz SMR spectrum subject to competitive bidding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Specialized Mobile Radio Service § 90.901 800 MHz SMR spectrum subject to competitive bidding. Mutually exclusive initial applications for 800 MHz band licenses in Spectrum Blocks A through V are subject to... 47 Telecommunication 5 2011-10-01 2011-10-01 false 800 MHz SMR spectrum subject to...

  17. 47 CFR 27.1021 - Reimbursement obligation of licensees at 1915-1920 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... licensees at 1915-1920 MHz. A licensee in the 1915-1920 MHz band (Lower H Block) shall, within 30 days of... MHz band on a pro rata shared basis with other Lower H Block licensees as set forth in paragraphs (a... this spectrum cover, collectively, at least forty (40) percent of the nation's population, the...

  18. 47 CFR 90.901 - 800 MHz SMR spectrum subject to competitive bidding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Specialized Mobile Radio Service § 90.901 800 MHz SMR spectrum subject to competitive bidding. Mutually exclusive initial applications for 800 MHz band licenses in Spectrum Blocks A through V are subject to... 47 Telecommunication 5 2012-10-01 2012-10-01 false 800 MHz SMR spectrum subject to...

  19. 47 CFR 90.901 - 800 MHz SMR spectrum subject to competitive bidding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Specialized Mobile Radio Service § 90.901 800 MHz SMR spectrum subject to competitive bidding. Mutually exclusive initial applications for 800 MHz band licenses in Spectrum Blocks A through V are subject to... 47 Telecommunication 5 2014-10-01 2014-10-01 false 800 MHz SMR spectrum subject to...

  20. 47 CFR 90.901 - 800 MHz SMR spectrum subject to competitive bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Specialized Mobile Radio Service § 90.901 800 MHz SMR spectrum subject to competitive bidding. Mutually exclusive initial applications for 800 MHz band licenses in Spectrum Blocks A through V are subject to... 47 Telecommunication 5 2010-10-01 2010-10-01 false 800 MHz SMR spectrum subject to...

  1. 47 CFR 90.901 - 800 MHz SMR spectrum subject to competitive bidding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Specialized Mobile Radio Service § 90.901 800 MHz SMR spectrum subject to competitive bidding. Mutually exclusive initial applications for 800 MHz band licenses in Spectrum Blocks A through V are subject to... 47 Telecommunication 5 2013-10-01 2013-10-01 false 800 MHz SMR spectrum subject to...

  2. 47 CFR 90.264 - Disaster communications between 2 and 10 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Disaster communications between 2 and 10 MHz... Bands § 90.264 Disaster communications between 2 and 10 MHz. (a) The use of any particular frequency... 10 MHz: (1) To provide communications circuits in emergency and/or disaster situations, where...

  3. 47 CFR 90.264 - Disaster communications between 2 and 10 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Disaster communications between 2 and 10 MHz... Bands § 90.264 Disaster communications between 2 and 10 MHz. (a) The use of any particular frequency... 10 MHz: (1) To provide communications circuits in emergency and/or disaster situations, where...

  4. 47 CFR 90.264 - Disaster communications between 2 and 10 MHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Disaster communications between 2 and 10 MHz... Bands § 90.264 Disaster communications between 2 and 10 MHz. (a) The use of any particular frequency... 10 MHz: (1) To provide communications circuits in emergency and/or disaster situations, where...

  5. 47 CFR 90.264 - Disaster communications between 2 and 10 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Disaster communications between 2 and 10 MHz... Bands § 90.264 Disaster communications between 2 and 10 MHz. (a) The use of any particular frequency... 10 MHz: (1) To provide communications circuits in emergency and/or disaster situations, where...

  6. 47 CFR 90.264 - Disaster communications between 2 and 10 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Disaster communications between 2 and 10 MHz... Bands § 90.264 Disaster communications between 2 and 10 MHz. (a) The use of any particular frequency... 10 MHz: (1) To provide communications circuits in emergency and/or disaster situations, where...

  7. 47 CFR 80.148 - Watch on 156.8 MHz (Channel 16).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Watch on 156.8 MHz (Channel 16). 80.148 Section... Watches § 80.148 Watch on 156.8 MHz (Channel 16). Each compulsory vessel, while underway, must maintain a watch for radiotelephone distress calls on 156.800 MHz whenever such station is not being used...

  8. 47 CFR 80.148 - Watch on 156.8 MHz (Channel 16).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Watch on 156.8 MHz (Channel 16). 80.148 Section... Watches § 80.148 Watch on 156.8 MHz (Channel 16). Each compulsory vessel, while underway, must maintain a watch for radiotelephone distress calls on 156.800 MHz whenever such station is not being used...

  9. 47 CFR 80.148 - Watch on 156.8 MHz (Channel 16).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Watch on 156.8 MHz (Channel 16). 80.148 Section... Watches § 80.148 Watch on 156.8 MHz (Channel 16). Each compulsory vessel, while underway, must maintain a watch for radiotelephone distress calls on 156.800 MHz whenever such station is not being used...

  10. 47 CFR 80.148 - Watch on 156.8 MHz (Channel 16).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Watch on 156.8 MHz (Channel 16). 80.148 Section... Watches § 80.148 Watch on 156.8 MHz (Channel 16). Each compulsory vessel, while underway, must maintain a watch for radiotelephone distress calls on 156.800 MHz whenever such station is not being used...

  11. 47 CFR 80.148 - Watch on 156.8 MHz (Channel 16).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Watch on 156.8 MHz (Channel 16). 80.148 Section... Watches § 80.148 Watch on 156.8 MHz (Channel 16). Each compulsory vessel, while underway, must maintain a watch for radiotelephone distress calls on 156.800 MHz whenever such station is not being used...

  12. 47 CFR 90.279 - Power limitations applicable to the 421-430 MHz band.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Power limitations applicable to the 421-430 MHz... Bands § 90.279 Power limitations applicable to the 421-430 MHz band. (a) Base station authorizations in the 421-430 MHz band will be subject to Effective Radiated Power (ERP) and Effective Antenna...

  13. 47 CFR 90.279 - Power limitations applicable to the 421-430 MHz band.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Power limitations applicable to the 421-430 MHz... Bands § 90.279 Power limitations applicable to the 421-430 MHz band. (a) Base station authorizations in the 421-430 MHz band will be subject to Effective Radiated Power (ERP) and Effective Antenna...

  14. 47 CFR 90.279 - Power limitations applicable to the 421-430 MHz band.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Power limitations applicable to the 421-430 MHz... Bands § 90.279 Power limitations applicable to the 421-430 MHz band. (a) Base station authorizations in the 421-430 MHz band will be subject to Effective Radiated Power (ERP) and Effective Antenna...

  15. 47 CFR 90.279 - Power limitations applicable to the 421-430 MHz band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Power limitations applicable to the 421-430 MHz... Bands § 90.279 Power limitations applicable to the 421-430 MHz band. (a) Base station authorizations in the 421-430 MHz band will be subject to Effective Radiated Power (ERP) and Effective Antenna...

  16. 47 CFR 90.279 - Power limitations applicable to the 421-430 MHz band.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Power limitations applicable to the 421-430 MHz... Bands § 90.279 Power limitations applicable to the 421-430 MHz band. (a) Base station authorizations in the 421-430 MHz band will be subject to Effective Radiated Power (ERP) and Effective Antenna...

  17. A 1400-MHz survey of 1478 Abell clusters of galaxies

    NASA Technical Reports Server (NTRS)

    Owen, F. N.; White, R. A.; Hilldrup, K. C.; Hanisch, R. J.

    1982-01-01

    Observations of 1478 Abell clusters of galaxies with the NRAO 91-m telescope at 1400 MHz are reported. The measured beam shape was deconvolved from the measured source Gaussian fits in order to estimate the source size and position angle. All detected sources within 0.5 corrected Abell cluster radii are listed, including the cluster number, richness class, distance class, magnitude of the tenth brightest galaxy, redshift estimate, corrected cluster radius in arcmin, right ascension and error, declination and error, total flux density and error, and angular structure for each source.

  18. Power sources for search and rescue 406 MHz beacons

    NASA Technical Reports Server (NTRS)

    Attia, Alan I.; Perrone, David E.

    1987-01-01

    The results of a study directed at the selection of a commercially available, safe, low cost, light weight and long storage life battery for search and rescue (Sarsat) 406 MHz emergency beacons are presented. In the course of this work, five electrochemical systems (lithium-manganese dioxide, lithium-carbon monofluoride, lithium-silver vanadium oxide, alkaline cells, and cadmium-mercuric oxide) were selected for limited experimental studies to determine their suitability for this application. Two safe, commercially available batteries (lithium-manganese dioxide and lithium-carbon monofluoride) which meet the near term requirements and several alternatives for the long term were identified.

  19. Design Methodology and Consideratios for NOVA 53 MHZ RF Cavities

    SciTech Connect

    Ader, C.; Wildman, D.W.; /Fermilab

    2010-05-19

    The NO?A Experiment will construct a detector optimized for electron neutrino detection in the existing Neutrino at Main Injector (NuMI) beamline. This beamline is capable of operating at 400 kW of primary beam power and the upgrade will allow up to 700 kW. The cavities will operate at 53 MHz and three of them will be installed in the Recycler beamline. Thermal stability of the cavities is crucial since this affects the tuning. Results of finite element thermal and structural analysis involving the copper RF cavity will be presented.

  20. Experimental solar radio spectrum analyzer (50-100 MHz)

    NASA Technical Reports Server (NTRS)

    Maxwell, A.

    1978-01-01

    Summarized is the work carried out under a NASA Grant covering the period 15 October 1977 to 14 January 1978. The grant provided funds for the acquisition of an experimental radio spectrum analyzer covering the band 50-100 MHz, for use in a program of solar radio observations. Components for the experimental analyzer were duly obtained, and the system was assembled, checked, and put into operation in early February 1978. The analyzer is working in an entirely satisfactory manner and, from the time that it has been put into operation, it has played an important part in the on-going research programs in solar radio astronomy being conducted.

  1. Stabilised electromagnetic levitation at 2-13 MHz

    NASA Technical Reports Server (NTRS)

    Danley, T. J.; Schiffman, R. A.; Weber, J. K. R.; Krishnan, S.; Rey, C. A.; Bruno, P. A.; Nordine, P. C.

    1991-01-01

    SEL, the Stabilised Electromagnetic Levitator, has been developed to exploit the unique design opportunities available in containerless microgravity experiments. Efficiency and versatility are obtained with multiple coils driven by individual broadband amplifiers whose phase and frequency are controlled. The heating and positioning fields are decoupled. Specimen translation, spin, and for liquids, shape may be adjusted. An open coil structure provides access for optical and diagnostic probes. Results of experiments with a prototype device are discussed. Levitating and heating materials on earth were demonstrated at frequencies up to 13 MHz.

  2. Heliospheric Tomography from IPS Data at 140 MHz

    NASA Astrophysics Data System (ADS)

    Mejia-Ambriz, J. C.; Jackson, B. V.; Gonzalez-Esparza, A.; Buffington, A.

    2014-12-01

    Interplanetary scintillation (IPS) from radio telescopes provides data to study density and velocity evolution of the solar wind and heliospheric disturbances. A tomography program developed at the University of California, San Diego, makes 3D reconstructions and forecasts of the inner heliosphere dynamics from IPS results. For the first time we incorporate 140 MHz IPS results from the MEXican Array Radio Telescope (MEXART) into the tomography program. We show that MEXART data complement observations from other radio-systems located at different longitudes, thus providing more complete heliospheric coverage.

  3. Fabrication and Measurements of 500 MHz Double Spoke Cavity

    SciTech Connect

    Park, HyeKyoung; Hopper, Christopher S.; Delayen, Jean R.

    2014-12-01

    A 500 MHz β0=1 double spoke cavity has been designed and optimized for a high velocity application such as a compact electron accelerator at the Center for Accelerator Science at Old Dominion University [1] and the fabrication was recently completed at Jefferson Lab. The geometry specific to the double spoke cavity required a variety of tooling and fixtures. Also a number of asymmetric weld joints were expected to make it difficult to maintain minimal geometric deviation from the design. This paper will report the fabrication procedure, resulting tolerance from the design, initial test results and the lessons learned from the first β0=1 double spoke cavity fabrication.

  4. Experimental and simulational result multipactors in 112 MHz QWR injector

    SciTech Connect

    Xin, T.; Ben-Zvi, I.; Belomestnykh, S.; Brutus, J. C.; Skaritka, J.; Wu, Q.; Xiao, B.

    2015-05-03

    The first RF commissioning of 112 MHz QWR superconducting electron gun was done in late 2014. The coaxial Fundamental Power Coupler (FPC) and Cathode Stalk (stalk) were installed and tested for the first time. During this experiment, we observed several multipacting barriers at different gun voltage levels. The simulation work was done within the same range. The comparison between the experimental observation and the simulation results are presented in this paper. The observations during the test are consisted with the simulation predictions. We were able to overcome most of the multipacting barriers and reach 1.8 MV gun voltage under pulsed mode after several round of conditioning processes.

  5. 2250-MHz High Efficiency Microwave Power Amplifier (HEMPA)

    NASA Technical Reports Server (NTRS)

    Sims, W. Herbert; Bell, Joseph L. (Technical Monitor)

    2001-01-01

    Tnis paper will focus on developing an exotic switching technique that enhances the DC-to-RF conversion efficiency of microwave power amplifiers. For years, switching techniques implemented in the 10 kHz to 30 MHz region have resulted in DC-to-RF conversion efficiencies of 90-95-percent. Currently amplifier conversion efficiency, in the 2-3 GHz region approaches, 10-20-percent. Using a combination of analytical modeling and hardware testing, a High Efficiency Microwave Power Amplifier was built that demonstrated conversion efficiencies four to five times higher than current state of the art.

  6. BNL 56 MHz HOM Damper Prototype Fabrication at JLab

    SciTech Connect

    Huque, Naeem A.; Daly, Edward F.; Clemens, William A.; McIntyre, Gary T.; Wu, Qiong; Seberg, Scott; Bellavia, Steve

    2015-09-01

    A prototype Higher-Order Mode (HOM) Damper was fabricated at JLab for the Relativistic Heavy-Ion Collider's (RHIC) 56 MHz cavity at Brookhaven National Laboratory (BNL). Primarily constructed from high RRR Niobium and Sapphire, the coaxial damper presented significant challenges in electron-beam welding (EBW), brazing and machining via acid etching. The results of the prototype operation brought about changes in the damper design, due to overheating braze alloys and possible multi-pacting. Five production HOM dampers are currently being fabricated at JLab. This paper outlines the challenges faced in the fabrication process, and the solutions put in place.

  7. BNL 56 MHz HOM damper prototype fabrication at JLAB

    SciTech Connect

    Huque, N.; McIntyre, G.; Daly, E. F.; Clemens, W.; Wu, Q.; Seberg, S.; Bellavia, S.

    2015-05-03

    A prototype Higher-Order Mode (HOM) Damper was fabricated at JLab for the Relativistic Heavy-Ion Collider’s (RHIC) 56 MHz cavity at Brookhaven National Laboratory (BNL). Primarily constructed from high RRR Niobium and Sapphire, the coaxial damper presented significant challenges in electron-beam welding (EBW), brazing and machining via acid etching. The results of the prototype operation brought about changes in the damper design, due to overheating braze alloys and possible multi-pacting. Five production HOM dampers are currently being fabricated at JLab. This paper outlines the challenges faced in the fabrication process, and the solutions put in place.

  8. Development of 325 MHz single spoke resonators at Fermilab

    SciTech Connect

    Apollinari, G.; Gonin, I.V.; Khabiboulline, T.N.; Lanfranco, G.; Mukherjee, A.; Ozelis, J.; Ristori, L.; Sergatskov, D.; Wagner, R.; Webber, R.; /Fermilab

    2008-08-01

    The High Intensity Neutrino Source (HINS) project represents the current effort at Fermilab to produce an 8-GeV proton linac based on 400 independently phased superconducting cavities. Eighteen ?=0.21 single spoke resonators, operating at 325 MHz, comprise the first stage of the linac cold section. In this paper we present the current status of the production and testing of the first two prototype cavities. This includes descriptions of the fabrication, frequency tuning, chemical polishing, high pressure rinse, and high-gradient cold tests.

  9. Internal field strength measurements in chick forebrains at 50, 147, and 450 MHz.

    PubMed

    Weil, C M; Spiegel, R J; Joines, W T

    1984-01-01

    This report describes some experimental measurements of the internal field levels induced within isolated chick-forebrains irradiated at 50, 147, and 450 MHz, under essentially the same conditions as those used in the in vitro calcium-ion efflux experiments. Ratios of incident power at 50/147 MHz and 147/450 MHz that are needed to establish the same probe output are given and comparisons made with values predicted by different spherical models. Data predicted by the layered-sphere model were found to be in close agreement with measured values for the 50/147-MHz ratio. Agreement for the 147/450-MHz ratio was poorer.

  10. 47 CFR 90.615 - Individual channels available in the General Category in 806-824/851-869 MHz band.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Category in 806-824/851-869 MHz band. 90.615 Section 90.615 Telecommunication FEDERAL COMMUNICATIONS... Governing Licensing and Use of Frequencies in the 806-824, 851-869, 896-901, and 935-940 MHz Bands Policies...-824 Mhz, 851-869 Mhz, 896-901 Mhz, and 935-940 Mhz Bands § 90.615 Individual channels available in...

  11. 47 CFR 90.615 - Individual channels available in the General Category in 806-824/851-869 MHz band.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Category in 806-824/851-869 MHz band. 90.615 Section 90.615 Telecommunication FEDERAL COMMUNICATIONS... Governing Licensing and Use of Frequencies in the 806-824, 851-869, 896-901, and 935-940 MHz Bands Policies...-824 Mhz, 851-869 Mhz, 896-901 Mhz, and 935-940 Mhz Bands § 90.615 Individual channels available in...

  12. 47 CFR 90.615 - Individual channels available in the General Category in 806-824/851-869 MHz band.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Category in 806-824/851-869 MHz band. 90.615 Section 90.615 Telecommunication FEDERAL COMMUNICATIONS... Governing Licensing and Use of Frequencies in the 806-824, 851-869, 896-901, and 935-940 MHz Bands Policies...-824 Mhz, 851-869 Mhz, 896-901 Mhz, and 935-940 Mhz Bands § 90.615 Individual channels available in...

  13. 47 CFR 90.615 - Individual channels available in the General Category in 806-824/851-869 MHz band.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Category in 806-824/851-869 MHz band. 90.615 Section 90.615 Telecommunication FEDERAL COMMUNICATIONS... Governing Licensing and Use of Frequencies in the 806-824, 851-869, 896-901, and 935-940 MHz Bands Policies...-824 Mhz, 851-869 Mhz, 896-901 Mhz, and 935-940 Mhz Bands § 90.615 Individual channels available in...

  14. 47 CFR 90.615 - Individual channels available in the General Category in 806-824/851-869 MHz band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Category in 806-824/851-869 MHz band. 90.615 Section 90.615 Telecommunication FEDERAL COMMUNICATIONS... Governing Licensing and Use of Frequencies in the 806-824, 851-869, 896-901, and 935-940 MHz Bands Policies...-824 Mhz, 851-869 Mhz, 896-901 Mhz, and 935-940 Mhz Bands § 90.615 Individual channels available in...

  15. 47 CFR 27.77 - Restriction on mobile and portable equipment in the 1695-1710 MHz and 1755-1780 MHz bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Restriction on mobile and portable equipment in the 1695-1710 MHz and 1755-1780 MHz bands. 27.77 Section 27.77 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS...

  16. 47 CFR 27.1136 - Protection of mobile satellite services in the 2000-2020 MHz and 2180-2200 MHz bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Protection of mobile satellite services in the... Protection of mobile satellite services in the 2000-2020 MHz and 2180-2200 MHz bands. An AWS licensee of the... satellite service operations in these bands. Any such AWS licensees must protect mobile satellite...

  17. 47 CFR 27.1136 - Protection of mobile satellite services in the 2000-2020 MHz and 2180-2200 MHz bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Protection of mobile satellite services in the... Operations § 27.1136 Protection of mobile satellite services in the 2000-2020 MHz and 2180-2200 MHz bands. An... duly authorized mobile satellite service operations in these bands. Any such AWS licensees must...

  18. 47 CFR 101.82 - Reimbursement and relocation expenses in the 2110-2150 MHz and 2160-2200 MHz bands.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Applications and Licenses... microwave link with one path in the 2130-2150 MHz band and the paired path in the 2180-2200 MHz band, the... to relocate the same fixed microwave link as set forth in paragraphs (c) and (d) of this section....

  19. 47 CFR 101.82 - Reimbursement and relocation expenses in the 2110-2150 MHz and 2160-2200 MHz bands.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Applications and Licenses... microwave link with one path in the 2130-2150 MHz band and the paired path in the 2180-2200 MHz band, the... to relocate the same fixed microwave link as set forth in paragraphs (c) and (d) of this section....

  20. 47 CFR 27.201 - WCS in the 2305-2320 MHz and 2345-2360 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false WCS in the 2305-2320 MHz and 2345-2360 MHz bands subject to competitive bidding. 27.201 Section 27.201 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES...

  1. 47 CFR 27.201 - WCS in the 2305-2320 MHz and 2345-2360 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false WCS in the 2305-2320 MHz and 2345-2360 MHz bands subject to competitive bidding. 27.201 Section 27.201 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES...

  2. 47 CFR 27.201 - WCS in the 2305-2320 MHz and 2345-2360 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false WCS in the 2305-2320 MHz and 2345-2360 MHz bands subject to competitive bidding. 27.201 Section 27.201 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES...

  3. 47 CFR 27.201 - WCS in the 2305-2320 MHz and 2345-2360 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false WCS in the 2305-2320 MHz and 2345-2360 MHz bands subject to competitive bidding. 27.201 Section 27.201 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES...

  4. 47 CFR 27.201 - WCS in the 2305-2320 MHz and 2345-2360 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false WCS in the 2305-2320 MHz and 2345-2360 MHz bands subject to competitive bidding. 27.201 Section 27.201 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES...

  5. Constraints on the FRB rate at 700-900 MHz

    NASA Astrophysics Data System (ADS)

    Connor, Liam; Lin, Hsiu-Hsien; Masui, Kiyoshi; Oppermann, Niels; Pen, Ue-Li; Peterson, Jeffrey B.; Roman, Alexander; Sievers, Jonathan

    2016-07-01

    Estimating the all-sky rate of fast radio bursts (FRBs) has been difficult due to small-number statistics and the fact that they are seen by disparate surveys in different regions of the sky. In this paper we provide limits for the FRB rate at 800 MHz based on the only burst detected at frequencies below 1.4 GHz, FRB 110523. We discuss the difficulties in rate estimation, particularly in providing an all-sky rate above a single fluence threshold. We find an implied rate between 700 and 900 MHz that is consistent with the rate at 1.4 GHz, scaling to 6.4^{+29.5}_{-5.0} × 10^3 sky-1 d-1 for an HTRU-like survey. This is promising for upcoming experiments below a GHz like CHIME and UTMOST, for which we forecast detection rates. Given 110523's discovery at 32σ with nothing weaker detected, down to the threshold of 8σ, we find consistency with a Euclidean flux distribution but disfavour steep distributions, ruling out γ > 2.2.

  6. Experimental Limits on Gravitational Waves in the MHz frequency Range

    SciTech Connect

    Lanza, Robert Jr.

    2015-03-01

    This thesis presents the results of a search for gravitational waves in the 1-11MHz frequency range using dual power-recycled Michelson laser interferometers at Fermi National Accelerator Laboratory. An unprecedented level of sensitivity to gravitational waves in this frequency range has been achieved by cross-correlating the output fluctuations of two identical and colocated 40m long interferometers. This technique produces sensitivities better than two orders of magnitude below the quantum shot-noise limit, within integration times of less than 1 hour. 95% confidence level upper limits are placed on the strain amplitude of MHz frequency gravitational waves at the 10-21 Hz-1/2 level, constituting the best direct limits to date at these frequencies. For gravitational wave power distributed over this frequency range, a broadband upper limit of 2.4 x 10-21Hz-1/2 at 95% confidence level is also obtained. This thesis covers the detector technology, the commissioning and calibration of the instrument, the statistical data analysis, and the gravitational wave limit results. Particular attention is paid to the end-to-end calibration of the instrument’s sensitivity to differential arm length motion, and so to gravitational wave strain. A detailed statistical analysis of the data is presented as well.

  7. Design and fabrication of a 40-MHz annular array transducer

    PubMed Central

    Ketterling, Jeffrey A.; Lizzi, Frederic L.; Aristizábal, Orlando; Turnbull, Daniel H.

    2006-01-01

    This paper investigates the feasibility of fabricating a 5-ring, focused annular array transducer operating at 40 MHz. The active piezoelectric material of the transducer was a 9-μm thick polyvinylidene fluoride (PVDF) film. One side of the PVDF was metallized with gold and forms the ground plane of the transducer. The array pattern of the transducer and electrical traces to each annulus were formed on a copper-clad polyimide film. The PVDF and polyimide were bonded with a thin layer of epoxy, pressed into a spherically curved shape, and then back filled with epoxy. A 5-ring transducer with equal area elements and 100 μm kerfs between annuli was fabricated and tested. The transducer had a total aperture of 6 mm and a geometric focus of 12 mm. The pulse/echo response from a quartz plate located at the geometric focus, two-way insertion loss (IL), complex impedance, electrical cross-talk, and lateral beamwidth were all measured for each annulus. The complex impedance data from each element were used to perform electrical matching and the measurements were repeated. After impedance matching, fc ≈ 36 MHz and BWs ranged from 31 to 39%. The ILs for the matched annuli ranged from −28 to −38 dB. PMID:16060516

  8. Very High Frequency (Beyond 100 MHz) PZT Kerfless Linear Arrays

    PubMed Central

    Wu, Da-Wei; Zhou, Qifa; Geng, Xuecang; Liu, Chang-Geng; Djuth, Frank; Shung, K. Kirk

    2010-01-01

    This paper presents the design, fabrication, and measurements of very high frequency kerfless linear arrays prepared from PZT film and PZT bulk material. A 12-µm PZT thick film fabricated from PZT-5H powder/solution composite and a piece of 15-µm PZT-5H sheet were used to fabricate 32-element kerfless high-frequency linear arrays with photolithography. The PZT thick film was prepared by spin-coating of PZT sol-gel composite solution. The thin PZT-5H sheet sample was prepared by lapping a PZT-5H ceramic with a precision lapping machine. The measured results of the 2 arrays were compared. The PZT film array had a center frequency of 120 MHz, a bandwidth of 60% with a parylene matching layer, and an insertion loss of 41 dB. The PZT ceramic sheet array was found to have a center frequency of 128 MHz with a poorer bandwidth (40% with a parylene matching layer) but a better sensitivity (28 dB insertion loss). PMID:19942516

  9. Cellular neoplastic transformation induced by 916 MHz microwave radiation.

    PubMed

    Yang, Lei; Hao, Dongmei; Wang, Minglian; Zeng, Yi; Wu, Shuicai; Zeng, Yanjun

    2012-08-01

    There has been growing concern about the possibility of adverse health effects resulting from exposure to microwave radiations, such as those emitted by mobile phones. The purpose of this study was to investigate the cellular neoplastic transformation effects of electromagnetic fields. 916 MHz continuous microwave was employed in our study to simulate the electromagnetic radiation of mobile phone. NIH/3T3 cells were adopted in our experiment due to their sensitivity to carcinogen or cancer promoter in environment. They were divided randomly into one control group and three microwave groups. The three microwave groups were exposed to 916 MHz EMF for 2 h per day with power density of 10, 50, and 90 w/m(2), respectively, in which 10 w/m(2) was close to intensity near the antenna of mobile phone. The morphology and proliferation of NIH/3T3 cells were examined and furthermore soft agar culture and animal carcinogenesis assay were carried out to determine the neoplastic promotion. Our experiments showed NIH/3T3 cells changed in morphology and proliferation after 5-8 weeks exposure and formed clone in soft agar culture after another 3-4 weeks depending on the exposure intensity. In the animal carcinogenesis study, lumps developed on the back of SCID mice after being inoculated into exposed NIH/3T3 cells for more than 4 weeks. The results indicate that microwave radiation can promote neoplastic transformation of NIH/3T3cells.

  10. Synchrotron Spectral Curvature from 22 MHZ to 23 GHZ

    NASA Technical Reports Server (NTRS)

    Kogut, Alan J.

    2012-01-01

    We combine surveys of the radio sky at frequencies 22 MHz to 1.4 GHz with data from the ARCADE-2 instrument at frequencies 3 GHz to 10 GHz to characterize the frequency spectrum of diffuse synchrotron emission in the Galaxy. The radio spectrum steepens with frequency from 22 MHz to 10 GHz. The projected spectral index at 23 GHz derived from the low-frequency data agrees well with independent measurements using only data at frequencies 23 GHz and above. Comparing the spectral index at 23 GHz to the value from previously published analyses allows extension of the model to higher frequencies. The combined data are consistent with a power-law index beta = -2.64 +/-= 0.03 at 0.31 GHz, steepening by an amount of Delta-beta = 0.07 every octave in frequency. Comparison of the radio data to models including the cosmic-ray energy spectrum suggests that any break in the synchrotron spectrum must occur at frequencies above 23 GHz.

  11. The 50-MHz meteor radar observation at Syowa Station, Antarctica

    NASA Technical Reports Server (NTRS)

    Tanaka, T.; Ogawa, T.; Igarashi, K.; Fujii, R.

    1985-01-01

    The 50-MHz Doppler radar installed at Syowa Station (69 deg 00'S, 39 deg 35'E), Antarctica, in 1982 can detect continuously a meteor echo if an operator assigns the meteor mode operation to the radar. The radar has two narrow antenna beams (4 deg in the horizontal plane), one toward geomagnetic south and the other toward approximately geographic south, with a crossing angle of about 33 deg. The minicomputer annexed to the radar controls the transmission and reception of a 50-MHz wave. If the receiver detects a meteor echo, the flag signal is sent to the computer. Then the computer begins to determine the echo range with a time resolution of 1 micro s and to sample every 200 microns/s for 1 s the Doppler signal and echo intensity at the particular range (R). The line-of-sight velocity (V sub D) of the echo trail is calculated from the output from the Doppler signal detection circuit having an offset frequency by using the so-called zero-crossing method. The echo amplitude decay time calculated by a least-mean square method is used to obtain the ambipolar diffusion coefficient (D) and then to calculate the echo height (H). About 120 day observations were made during 1982-1983. Some early results are presented. magnetic tapes together with V sub D, D, H and R for later analysis in Japan. About 120 day observation were made during 1982-1983. Some early results are presented.

  12. Ultrahigh Frequency (100 MHz-300 MHz) Ultrasonic Transducers for Optical Resolution Medical Imagining.

    PubMed

    Fei, Chunlong; Chiu, Chi Tat; Chen, Xiaoyang; Chen, Zeyu; Ma, Jianguo; Zhu, Benpeng; Shung, K Kirk; Zhou, Qifa

    2016-01-01

    High resolution ultrasonic imaging requires high frequency wide band ultrasonic transducers, which produce short pulses and highly focused beam. However, currently the frequency of ultrasonic transducers is limited to below 100 MHz, mainly because of the challenge in precise control of fabrication parameters. This paper reports the design, fabrication, and characterization of sensitive broadband lithium niobate (LiNbO3) single element ultrasonic transducers in the range of 100-300 MHz, as well as their applications in high resolution imaging. All transducers were built for an f-number close to 1.0, which was achieved by press-focusing the piezoelectric layer into a spherical curvature. Characterization results demonstrated their high sensitivity and a -6 dB bandwidth greater than 40%. Resolutions better than 6.4 μm in the lateral direction and 6.2 μm in the axial direction were achieved by scanning a 4 μm tungsten wire target. Ultrasonic biomicroscopy images of zebrafish eyes were obtained with these transducers which demonstrate the feasibility of high resolution imaging with a performance comparable to optical resolution. PMID:27329379

  13. Comparison of 250 MHz R10K Origin 2000 and 400 MHz Origin 2000 Using NAS Parallel Benchmarks

    NASA Technical Reports Server (NTRS)

    Turney, Raymond D.; Thigpen, William W. (Technical Monitor)

    2001-01-01

    This report describes results of benchmark tests on Steger, a 250 MHz Origin 2000 system with R10K processors, currently installed at the NASA Ames National Advanced Supercomputing (NAS) facility. For comparison purposes, the tests were also run on Lomax, a 400 MHz Origin 2000 with R12K processors. The BT, LU, and SP application benchmarks in the NAS Parallel Benchmark Suite and the kernel benchmark FT were chosen to measure system performance. Having been written to measure performance on Computational Fluid Dynamics applications, these benchmarks are assumed appropriate to represent the NAS workload. Since the NAS runs both message passing (MPI) and shared-memory, compiler directive type codes, both MPI and OpenMP versions of the benchmarks were used. The MPI versions used were the latest official release of the NAS Parallel Benchmarks, version 2.3. The OpenMP versions used were PBN3b2, a beta version that is in the process of being released. NPB 2.3 and PBN3b2 are technically different benchmarks, and NPB results are not directly comparable to PBN results.

  14. 201 MHz Cavity R&D for MUCOOL and MICE

    SciTech Connect

    Li, Derun; Virostek, Steve; Zisman, Michael; Norem, Jim; Bross,Alan; Moretti, Alfred; Norris, Barry; Torun, Yagmur; Phillips, Larry; Rimmer, Robert; Stirbet, Mircea; Reep, Michael; Summers, Don

    2006-06-23

    We describe the design, fabrication, analysis and preliminary testing of the prototype 201 MHz copper cavity for a muon ionization cooling channel. Cavity applications include the Muon Ionization Cooling Experiment (MICE) as well as cooling channels for a neutrino factory or a muon collider. This cavity was developed by the US muon cooling (MUCOOL) collaboration and is being tested in the MUCOOL Test Area (MTA) at Fermilab. To achieve a high accelerating gradient, the cavity beam irises are terminated by a pair of curved, thin beryllium windows. Several fabrication methods developed for the cavity and windows are novel and offer significant cost savings as compared to conventional construction methods. The cavity's thermal and structural performances are simulated with an FEA model. Preliminary high power RF commissioning results will be presented.

  15. A 20 MHz CMOS reorder buffer for a superscalar microprocessor

    NASA Technical Reports Server (NTRS)

    Lenell, John; Wallace, Steve; Bagherzadeh, Nader

    1992-01-01

    Superscalar processors can achieve increased performance by issuing instructions out-of-order from the original sequential instruction stream. Implementing an out-of-order instruction issue policy requires a hardware mechanism to prevent incorrectly executed instructions from updating register values. A reorder buffer can be used to allow a superscalar processor to issue instructions out-of-order and maintain program correctness. This paper describes the design and implementation of a 20MHz CMOS reorder buffer for superscalar processors. The reorder buffer is designed to accept and retire two instructions per cycle. A full-custom layout in 1.2 micron has been implemented, measuring 1.1058 mm by 1.3542 mm.

  16. Multipacting optimization of a 750 MHz rf dipole

    SciTech Connect

    Delayen, Jean R.; Castillo, Alejandro

    2014-12-01

    Crab crossing schemes have been proposed to re-instate luminosity degradation due to crossing angles at the interaction points in next generation colliders to avoid the use of sharp bending magnets and their resulting large synchrotron radiation generation, highly undessirable in the detector region. The rf dipole has been considered for a different set of applications in several machines, both rings and linear colliders. We present in this paper a study of the effects on the multipacting levels and location depending on geometrical variations on the design for a crabbing/deflecting application in a high current (3/0.5 A), high repetition (750 MHz) electron/proton collider, as a matter to provide a comparison point for similar applications of rf dipoles.

  17. 915-MHz Radar Wind Profiler (915RWP) Handbook

    SciTech Connect

    Coulter, R

    2005-01-01

    The 915 MHz radar wind profiler/radio acoustic sounding system (RWP/RASS) measures wind profiles and backscattered signal strength between (nominally) 0.1 km and 5 km and virtual temperature profiles between 0.1 km and 2.5 km. It operates by transmitting electromagnetic energy into the atmosphere and measuring the strength and frequency of backscattered energy. Virtual temperatures are recovered by transmitting an acoustic signal vertically and measuring the electromagnetic energy scattered from the acoustic wavefront. Because the propagation speed of the acoustic wave is proportional to the square root of the virtual temperature of the air, the virtual temperature can be recovered by measuring the Doppler shift of the scattered electromagnetic wave.

  18. Imaging Jupiter's radiation belts down to 127 MHz with LOFAR

    NASA Astrophysics Data System (ADS)

    Girard, J. N.; Zarka, P.; Tasse, C.; Hess, S.; de Pater, I.; Santos-Costa, D.; Nenon, Q.; Sicard, A.; Bourdarie, S.; Anderson, J.; Asgekar, A.; Bell, M. E.; van Bemmel, I.; Bentum, M. J.; Bernardi, G.; Best, P.; Bonafede, A.; Breitling, F.; Breton, R. P.; Broderick, J. W.; Brouw, W. N.; Brüggen, M.; Ciardi, B.; Corbel, S.; Corstanje, A.; de Gasperin, F.; de Geus, E.; Deller, A.; Duscha, S.; Eislöffel, J.; Falcke, H.; Frieswijk, W.; Garrett, M. A.; Grießmeier, J.; Gunst, A. W.; Hessels, J. W. T.; Hoeft, M.; Hörandel, J.; Iacobelli, M.; Juette, E.; Kondratiev, V. I.; Kuniyoshi, M.; Kuper, G.; van Leeuwen, J.; Loose, M.; Maat, P.; Mann, G.; Markoff, S.; McFadden, R.; McKay-Bukowski, D.; Moldon, J.; Munk, H.; Nelles, A.; Norden, M. J.; Orru, E.; Paas, H.; Pandey-Pommier, M.; Pizzo, R.; Polatidis, A. G.; Reich, W.; Röttgering, H.; Rowlinson, A.; Schwarz, D.; Smirnov, O.; Steinmetz, M.; Swinbank, J.; Tagger, M.; Thoudam, S.; Toribio, M. C.; Vermeulen, R.; Vocks, C.; van Weeren, R. J.; Wijers, R. A. M. J.; Wucknitz, O.

    2016-03-01

    Context. With the limited amount of in situ particle data available for the innermost region of Jupiter's magnetosphere, Earth-based observations of the giant planets synchrotron emission remain the sole method today of scrutinizing the distribution and dynamical behavior of the ultra energetic electrons magnetically trapped around the planet. Radio observations ultimately provide key information about the origin and control parameters of the harsh radiation environment. Aims: We perform the first resolved and low-frequency imaging of the synchrotron emission with LOFAR. At a frequency as low as 127 MHz, the radiation from electrons with energies of ~1-30 MeV are expected, for the first time, to be measured and mapped over a broad region of Jupiter's inner magnetosphere. Methods: Measurements consist of interferometric visibilities taken during a single 10-hour rotation of the Jovian system. These visibilities were processed in a custom pipeline developed for planetary observations, combining flagging, calibration, wide-field imaging, direction-dependent calibration, and specific visibility correction for planetary targets. We produced spectral image cubes of Jupiter's radiation belts at the various angular, temporal, and spectral resolutions from which flux densities were measured. Results: The first resolved images of Jupiter's radiation belts at 127-172 MHz are obtained with a noise level ~20-25 mJy/beam, along with total integrated flux densities. They are compared with previous observations at higher frequencies. A greater extent of the synchrotron emission source (≥4 RJ) is measured in the LOFAR range, which is the signature - as at higher frequencies - of the superposition of a "pancake" and an isotropic electron distribution. Asymmetry of east-west emission peaks is measured, as well as the longitudinal dependence of the radial distance of the belts, and the presence of a hot spot at λIII = 230° ± 25°. Spectral flux density measurements are on the low

  19. Pulsar polarisation below 200 MHz: Average profiles and propagation effects

    NASA Astrophysics Data System (ADS)

    Noutsos, A.; Sobey, C.; Kondratiev, V. I.; Weltevrede, P.; Verbiest, J. P. W.; Karastergiou, A.; Kramer, M.; Kuniyoshi, M.; Alexov, A.; Breton, R. P.; Bilous, A. V.; Cooper, S.; Falcke, H.; Grießmeier, J.-M.; Hassall, T. E.; Hessels, J. W. T.; Keane, E. F.; Osłowski, S.; Pilia, M.; Serylak, M.; Stappers, B. W.; ter Veen, S.; van Leeuwen, J.; Zagkouris, K.; Anderson, K.; Bähren, L.; Bell, M.; Broderick, J.; Carbone, D.; Cendes, Y.; Coenen, T.; Corbel, S.; Eislöffel, J.; Fender, R.; Garsden, H.; Jonker, P.; Law, C.; Markoff, S.; Masters, J.; Miller-Jones, J.; Molenaar, G.; Osten, R.; Pietka, M.; Rol, E.; Rowlinson, A.; Scheers, B.; Spreeuw, H.; Staley, T.; Stewart, A.; Swinbank, J.; Wijers, R.; Wijnands, R.; Wise, M.; Zarka, P.; van der Horst, A.

    2015-04-01

    Aims: We present the highest-quality polarisation profiles to date of 16 non-recycled pulsars and four millisecond pulsars, observed below 200 MHz with the LOFAR high-band antennas. Based on the observed profiles, we perform an initial investigation of expected observational effects resulting from the propagation of polarised emission in the pulsar magnetosphere and the interstellar medium. Methods: The polarisation data presented in this paper have been calibrated for the geometric-projection and beam-shape effects that distort the polarised information as detected with the LOFAR antennas. We have used RM Synthesis to determine the amount of Faraday rotation in the data at the time of the observations. The ionospheric contribution to the measured Faraday rotation was estimated using a model of the ionosphere. To study the propagation effects, we have compared our low-frequency polarisation observations with archival data at 240, 400, 600, and 1400 MHz. Results: The predictions of magnetospheric birefringence in pulsars have been tested using spectra of the pulse width and fractional polarisation from multifrequency data. The derived spectra offer only partial support for the expected effects of birefringence on the polarisation properties, with only about half of our sample being consistent with the model's predictions. It is noted that for some pulsars these measurements are contaminated by the effects of interstellar scattering. For a number of pulsars in our sample, we have observed significant variations in the amount of Faraday rotation as a function of pulse phase, which is possibly an artefact of scattering. These variations are typically two orders of magnitude smaller than that observed at 1400 MHz by Noutsos et al. (2009), for a different sample of southern pulsars. In this paper we present a possible explanation for the difference in magnitude of this effect between the two frequencies, based on scattering. Finally, we have estimated the magnetospheric

  20. Performance characteristics of a 425 MHz RFQ linac

    SciTech Connect

    Stovall, J.E.; Crandall, K.R.; Hamm, R.W.

    1980-01-01

    A radio-frequency quadrupole (RFQ) focused proton linac has been developed and successfully tested at the Los Alamos Scientific Laboratory (LASL) for the purpose of evaluating its performance and applicability as a low-beta accelerator. The geometry of the structure was designed to accept a 100-keV beam, focus, bunch, and accelerate it to 640 keV in 1.1 m with a high-capture efficiency and minimum emittance growth. The accelerator test facility includes an injector, low-energy transport section for transverse matching, and a high-energy transport section for analysis of the beam properties. The accelerator cavity is exited through a manifold powered by a 450-MHz klystron. Diagnostic instrumentation was prepared to facilitate operation of the accelerator and to analyze its performance. Measurements of the beam properties are presented and compared with the expected properties resulting from numerical calculations of the beam dynamics.

  1. The first operation of 56 MHz SRF cavity in RHIC

    SciTech Connect

    Wu, Q.; Belomestnykh, S.; Ben-Zvi, I.; Blaskiewicz, M.; DeSanto, L.; Goldberg, D.; Harvey, M.; Hayes, T.; McIntyre, G.; Mernick, K.; Orfin, P.; Seberg, S.; Severino, F.; Smith, K.; Than, R.; Zaltsman, A.

    2015-05-03

    A 56 MHz superconducting RF cavity has been designed, fabricated and installed in the Relativistic Heavy Ion Collider (RHIC). The cavity operates at 4.4 K with a “quiet helium source” to isolate the cavity from environmental acoustic noise. The cavity is a beam driven quarter wave resonator. It is detuned and damped during injection and acceleration cycles and is brought to operation only at store energy. For a first test operation, the cavity voltage was stabilized at 300 kV with full beam current. Within both Au + Au and asymmetrical Au + He3 collisions, luminosity improvement was detected from direct measurement, and the hourglass effect was reduced. One higher order mode (HOM) coupler was installed on the cavity. We report in this paper on our measurement of a broadband HOM spectrum excited by the Au beam.

  2. Developments of 700-Mhz 5-Cell Superconducting Cavities for APT

    SciTech Connect

    T. Tajima; K. C. D. Chan; R. C. Gentzlinger; W. B. Haynes; J. P. Kelley; F. L. Krawczyk; M. A. Madrid; D. I. Montoya; D. L. Schrage; A. H. Shapiro; J. Mammosser

    2001-07-01

    We have manufactured a total of six {beta} = 0.64, 700-MHz 5-cell cavities. The APT (Accelerator Production of Tritium) specification requires Q{sub 0} > 5 x 10{sup 9} at an accelerating field of 5 MV/m. So far, the results of vertical tests have shown maximum accelerating fields of 12 MV/m (peak surface field of 41 MV/m) and maximum low-field Q{sub 0} of 3.6 x 10{sup 10} at 2 K. The present limitations are available input power, field emission and quench. This type of cavities will also be used for an ADTF (Accelerator-Driven Test Facility) for AAA (Advanced Accelerator Applications) project.

  3. Description of a New 400 MHZ Bandwidth Chirp Transform Spectrometer

    NASA Astrophysics Data System (ADS)

    Paganini, Lucas; Hartogh, Paul

    A new chirp transform spectrometer (CTS) with a bandwidth of 400 MHz and a spectral resolution of 100 kHz has been developed. The CTS is deviced using a digital chirp generator and a preprocessing unit based on a Complementary Metal Oxide Semiconductor (CMOS) and an Application-Specific Integrated Circuit (ASIC). A build in PC 104 computer handles the process control and the external communication via Ethernet and a Transistor-Transistor Logic (TTL) interface. The CTS has been applied to atmospheric science, i.e., a 25-K noise temperature, 22-GHz water vapor, and a 142-GHz ozone system. Astronomical observations have been performed using the Heinrich Hertz submillimeter telescope. In this paper, we describe the function of the CTS and provide information about its functional performance.

  4. Jupiter's radio spectrum from 74 MHz up to 8 GHz

    NASA Astrophysics Data System (ADS)

    de Pater, Imke; Butler, B. J.; Green, D. A.; Strom, R.; Millan, R.; Klein, M. J.; Bird, M. K.; Funke, O.; Neidhöfer, J.; Maddalena, R.; Sault, R. J.; Kesteven, M.; Smits, D. P.; Hunstead, R.

    2003-06-01

    We carried out a brief campaign in September 1998 to determine Jupiter's radio spectrum at frequencies spanning a range from 74 MHz up to 8 GHz. Eleven different telescopes were used in this effort, each uniquely suited to observe at a particular frequency. We find that Jupiter's spectrum is basically flat shortwards of 1-2 GHz, and drops off steeply at frequencies greater than 2 GHz. We compared the 1998 spectrum with a spectrum (330 MHz-8 GHz) obtained in June 1994, and report a large difference in spectral shape, being most pronounced at the lowest frequencies. The difference seems to be linear with log(ν), with the largest deviations at the lowest frequencies (ν). We have compared our spectra with calculations of Jupiter's synchrotron radiation using several published models. The spectral shape is determined by the energy-dependent spatial distribution of the electrons in Jupiter's magnetic field, which in turn is determined by the detailed diffusion process across L-shells and in pitch angle, as well as energy-dependent particle losses. The spectral shape observed in September 1998 can be matched well if the electron energy spectrum at L = 6 is modeled by a double power law E- a (1+( E/ E0)) - b, with a = 0.4, b = 3, E0 = 100 MeV, and a lifetime against local losses τ 0 = 6 × 10 7 s. In June 1994 the observations can be matched equally well with two different sets of parameters: (1) a = 0.6, b = 3, E0 = 100 MeV, τ 0 = 6 × 10 7 s, or (2) a = 0.4, b = 3, E0 = 100 MeV, τ 0 = 8.6 × 10 6 s. We attribute the large variation in spectral shape between 1994 and 1998 to pitch angle scattering, coulomb scattering and/or energy degradation by dust in Jupiter's inner radiation belts.

  5. 47 CFR 15.323 - Specific requirements for devices operating in the 1920-1930 MHz sub-band.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the 1920-1930 MHz sub-band. 15.323 Section 15.323 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... requirements for devices operating in the 1920-1930 MHz sub-band. (a) Operation shall be contained within the 1920-1930 MHz band. The emission bandwidth shall be less then 2.5 MHz. The power level shall be...

  6. 47 CFR 15.323 - Specific requirements for devices operating in the 1920-1930 MHz sub-band.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the 1920-1930 MHz sub-band. 15.323 Section 15.323 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... requirements for devices operating in the 1920-1930 MHz sub-band. (a) Operation shall be contained within the 1920-1930 MHz band. The emission bandwidth shall be less then 2.5 MHz. The power level shall be...

  7. 77 FR 18991 - Channel Spacing and Bandwidth Limitations for Certain Economic Area (EA)-Based 800 MHz...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-29

    ... spectrum in the 800 MHz band for EA-based licensing in the 800 MHz SMR First Report and Order, at 61 FR... available spectrum within the block.'' The Commission also adopted an out-of-band emission requirement that... the 800 MHz band in the 800 MHz Reconfiguration Report and Order, at 69 FR 67823, Nov. 22, 2004,...

  8. The 2002 Leonids Using 28 MHz Ham-band Radio Observations (HRO) over = Japan

    NASA Astrophysics Data System (ADS)

    Usui, T.; Ogawa, H.; Hashimoto, T.; Ohnishi, K.; Yaguchi, N.; = Maegawa, K.

    2002-12-01

    The 2002 Leonids were expected to present a spectacular appearance = over Europe and America. No spectacular appearance was expected in Japan. On = the evening of November 17 (UT), however, the 1965 dust trail was predicted = to approach the Earth closely. Therefore, Japanese observers tried to = detect this trail using 28 MHz radio. This is because 28 MHz observations can = detect fainter meteor echoes than 53 MHz observations which are prevalent in Japan. = This study shows the observing method and results of 28 MHz observations of the = 2002 Leonids. We found that the Leonids were detectable for longer at 28 MHz than at = 53.75 MHz. This indicates that the distribution of fainter (smaller) meteors is = wider than that of larger ones.

  9. Beam dynamics and expected RHIC performance with 56MHz RF upgrade

    SciTech Connect

    Fedotov,A.V.; Ben-Zvi, I.

    2009-05-04

    An upgrade of the RHIC storage RF system with a superconducting 56 MHz cavity was recently proposed. This upgrade will provide a significant increase in the acceptance of the RHIC 197 MHz storage RF bucket. This paper summarizes simulations of beam evolution due to intra-beam scattering (IBS) for beam parameters expected with the 56 MHz SRF cavity upgrade. Expected luminosity improvements are shown for Au ions at 100 GeV/nucleon and protons at 250 GeV.

  10. Observations of IPS radio sources at 140 MHz with the Mexican Array Radio Telescope (MEXART)

    NASA Astrophysics Data System (ADS)

    Mejia-Ambriz, Julio-Cesar; Villanueva-Hernandez, Pablo; Gonzalez-Esparza, Americo; Aguilar-Rodriguez, Ernesto; Mendoza-Torrez, Jose Eduardo; Carrillo-Vargas, Armando; Andrade-Mascote, Ernesto

    The MEXART is a dedicated transit station to perform Interplanetary Scintillation (IPS) ob-servations. The array of 4096 full wavelenght dipoles has a collecting area of 9600 square meters, the operation frequency is 140 MHz with a bandwidth of 2 MHz. Recently we began the IPS observations with the instrument. We report a list of IPS radio sources observed at 140 MHz. We perform an analysis of the scintillation index (m) versus the elongation angle to obtain the first g values given by the instrument for some radio sources. We report the single station solar wind velocity fitting model adapted at 140 MHz based on Manoharan and Ananthakrishnan (1990).

  11. DETECTION AND FLUX DENSITY MEASUREMENTS OF THE MILLISECOND PULSAR J2145–0750 BELOW 100 MHz

    SciTech Connect

    Dowell, J.; Taylor, G. B.; Craig, J.; Henning, P. A.; Schinzel, F.; Ray, P. S.; Blythe, J. N.; Clarke, T.; Helmboldt, J. F.; Ellingson, S. W.; Wolfe, C. N.; Lazio, T. J. W.; Stovall, K.

    2013-09-20

    We present flux density measurements and pulse profiles for the millisecond pulsar PSR J2145–0750 spanning 37 to 81 MHz using data obtained from the first station of the Long Wavelength Array. These measurements represent the lowest frequency detection of pulsed emission from a millisecond pulsar to date. We find that the pulse profile is similar to that observed at 102 MHz. We also find that the flux density spectrum between ≈40 MHz to 5 GHz is suggestive of a break and may be better fit by a model that includes spectral curvature with a rollover around 730 MHz rather than a single power law.

  12. 78 FR 48621 - Service Rules for Advanced Wireless Services in the 2000-2020 MHz and 2180-2200 MHz Bands, etc.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-09

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS... 2180-2200 MHz Bands, etc. AGENCY: Federal Communications Commission. ACTION: Final rule; announcement of effective date. SUMMARY: In this document, the Commission announces that the Office of...

  13. Fast 704 MHz Ferroelectric Tuner for Superconducting Cavities

    SciTech Connect

    Jay L. Hirshfield

    2012-04-12

    The Omega-P SBIR project described in this Report has as its goal the development, test, and evaluation of a fast electrically-controlled L-band tuner for BNL Energy Recovery Linac (ERL) in the Electron Ion Collider (EIC) upgrade of the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). The tuner, that employs an electrically-controlled ferroelectric component, is to allow fast compensation to cavity resonance changes. In ERLs, there are several factors which significantly affect the amount of power required from the wall-plug to provide the RF-power level necessary for the operation. When beam loading is small, the power requirements are determined by (i) ohmic losses in cavity walls, (ii) fluctuations in amplitude and/or phase for beam currents, and (iii) microphonics. These factors typically require a substantial change in the coupling between the cavity and the feeding line, which results in an intentional broadening of the cavity bandwidth, which in turn demands a significant amount of additional RF power. If beam loading is not small, there is a variety of beam-drive phase instabilities to be managed, and microphonics will still remain an issue, so there remain requirements for additional power. Moreover ERL performance is sensitive to changes in beam arrival time, since any such change is equivalent to phase instability with its vigorous demands for additional power. In this Report, we describe the new modular coaxial tuner, with specifications suitable for the 704 MHz ERL application. The device would allow changing the RF-coupling during the cavity filling process in order to effect significant RF power savings, and also will provide rapid compensation for beam imbalance and allow for fast stabilization against phase fluctuations caused by microphonics, beam-driven instabilities, etc. The tuner is predicted to allow a reduction of about ten times in the required power from the RF source, as compared to a compensation system

  14. Commissioning of the 112 MHz SRF Gun and 500 MHz bunching cavities for the CeC PoP Linac

    SciTech Connect

    Belomestnykh, S.; Ben-Zvi, I.; Brutus, J. C.; Litvinenko, V.; McIntosh, P.; Moss, A.; Narayan, G.; Orfin, P.; Pinayev, I.; Rao, T.; Skaritka, J.; Smith, K.; Than, R.; Tuozzolo, J.; Wang, E.; Wheelhouse, A.; Wu, Q.; Xiao, B.; Xin, T.; Xu, W.; Zaltsman, A.

    2015-05-03

    The Coherent electron Cooling Proof-of-Principle (CeC PoP) experiment at BNL includes a short electron linac. During Phase 1, a 112 MHz superconducting RF photo-emission gun and two 500 MHz normal conducting bunching cavities were installed and are under commissioning. The paper describes the Phase1 linac layout and presents commissioning results for the cavities and associated RF, cryogenic and other sub-systems

  15. Adaptive optics optical coherence tomography at 1 MHz.

    PubMed

    Kocaoglu, Omer P; Turner, Timothy L; Liu, Zhuolin; Miller, Donald T

    2014-12-01

    Image acquisition speed of optical coherence tomography (OCT) remains a fundamental barrier that limits its scientific and clinical utility. Here we demonstrate a novel multi-camera adaptive optics (AO-)OCT system for ophthalmologic use that operates at 1 million A-lines/s at a wavelength of 790 nm with 5.3 μm axial resolution in retinal tissue. Central to the spectral-domain design is a novel detection channel based on four high-speed spectrometers that receive light sequentially from a 1 × 4 optical switch assembly. Absence of moving parts enables ultra-fast (50ns) and precise switching with low insertion loss (-0.18 dB per channel). This manner of control makes use of all available light in the detection channel and avoids camera dead-time, both critical for imaging at high speeds. Additional benefit in signal-to-noise accrues from the larger numerical aperture afforded by the use of AO and yields retinal images of comparable dynamic range to that of clinical OCT. We validated system performance by a series of experiments that included imaging in both model and human eyes. We demonstrated the performance of our MHz AO-OCT system to capture detailed images of individual retinal nerve fiber bundles and cone photoreceptors. This is the fastest ophthalmic OCT system we know of in the 700 to 915 nm spectral band.

  16. Fade Measurements into Buildings from 500 to 3000 MHz

    NASA Technical Reports Server (NTRS)

    Vogel, Wolfhard J.; Torrence, Geoffrey W.

    1996-01-01

    Slant-path fade measurements from 500 to 3000 MHz were made into six different buildings employing a vector network analyzer, a tower-mounted transmitting antenna and an automatically positioned receiving antenna. The objective of the measurements was to provide information for satellite audio broadcasting and personal communications satellite design on the correlation of fading inside buildings. Fades were measured with 5 cm spatial separation and every 0.2 percent of the frequency. Median fades ranged from 10 to 20 dB in woodframe houses with metal roofs and walls without and with an aluminum heat shield, respectively. The median decorrelation distance was from 0.5 to 1.1. m and was independent of frequency. The attenuation into the buildings increased only moderately with frequency in most of the buildings with a median slope of about 1 to 3 db/GHz, but increased fastest in the least attenuating building with a slope of 5 dB/GHz. The median decorrelation bandwidth ranged from 1.2 to 3.8 percent of frequency in five of the buildings, and was largest in the least attenuating building, with 20.2 percent of frequency.

  17. Fade Measurements into Buildings from 500 to 3000 MHz

    NASA Technical Reports Server (NTRS)

    Vogel, Wolfhard J.; Torrence, Geoffrey W.

    1996-01-01

    Slant-path fade measurements from 500 to 3000 MHz were made into six different buildings employing a vector network analyzer, a tower-mounted transmitting antenna and an automatically positioned receiving antenna. The objective of the measurements was to provide information for satellite audio broadcasting and personal communications satellite design on the correlation of fading inside buildings. Fades were measured with 5 cm spatial separation and every 0.2% of the frequency. Median fades ranged from 10 to 20 dB in woodframe houses with metal roofs and walls without and with an aluminum heatshield, respectively. The median decorrelation distance was from 0.5 to 1.1 m and was independent of frequency. The attenuation into the buildings increased only moderately with frequency in most of the buildings with a median slope of about 1 to 3 dB/GHz, but increased fastest in the least attenuating building with a slope of 5 dB/GHz. The median decorrelation bandwidth ranged from 1.2 to 3.8% of frequency in five of the buildings, and was largest in the least attenuating building, with 20.2% of frequency.

  18. Electrical impedance myography at frequencies up to 2 MHz.

    PubMed

    Shiffman, C A; Kashuri, H; Aaron, R

    2008-06-01

    Extension of the frequency range of electrical impedance myography (EIM) to 2 MHz discloses a major rise in the reactance of muscle above 3-500 kHz, together with a slow decrease in the resistance consonant with the Kramers-Kronig relations. This 'upturn' phenomenon is found when the distant current electrode configuration of EIM is employed, but not when the current electrodes are placed close to the voltage measuring area. In that case the impedance qualitatively mimics the commonly used 3-element resistor-capacitor model. The possibility that the upturn is an artifact of the measuring system rather than a true property of the tissue is examined in detail. In particular, experiments are reported which argue against the transmission line mechanism proposed to explain similar increases in reactance in some high frequency whole-body BIA studies. Also, scaling of X versus R plots for muscle segments of different lengths strongly suggests that the upturn is as much a property of the underlying tissue as is the low frequency maximum in reactance. PMID:18544820

  19. Merged and corrected 915 MHz Radar Wind Profiler moments

    SciTech Connect

    Jonathan Helmus,Virendra Ghate, Frederic Tridon

    2014-06-25

    The radar wind profiler (RWP) present at the SGP central facility operates at 915 MHz and was reconfigured in early 2011, to collect key sets of measurements for precipitation and boundary layer studies. The RWP is configured to run in two main operating modes: a precipitation (PR) mode with frequent vertical observations and a boundary layer (BL) mode that is similar to what has been traditionally applied to RWPs. To address issues regarding saturation of the radar signal, range resolution and maximum range, the RWP PR mode is set to operate with two different pulse lengths, termed as short pulse (SP) and long pulse (LP). Please refer to the RWP handbook (Coulter, 2012) for further information. Data from the RWP PR-SP and PR-LP modes have been extensively used to study deep precipitating clouds, especially their dynamical structure as the RWP data does not suffer from signal attenuation during these conditions (Giangrande et al., 2013). Tridon et al. (2013) used the data collected during the Mid-latitude Continental Convective Cloud Experiment (MC3E) to improve the estimation of noise floor of the RWP recorded Doppler spectra.

  20. Solar S-bursts at Frequencies of 10 - 30 MHz

    NASA Astrophysics Data System (ADS)

    Melnik, V. N.; Konovalenko, A. A.; Rucker, H. O.; Dorovskyy, V. V.; Abranin, E. P.; Lecacheux, A.; Lonskaya, A. S.

    2010-06-01

    Solar S-bursts observed by the radio telescope UTR-2 in the period 2001 - 2002 are studied. The bursts chosen for a detailed analysis occurred in the periods 23 - 26 May 2001, 13 - 16 and 27 - 39 July 2002 during three solar radio storms. More than 800 S-bursts were registered in these days. Properties of S-bursts are studied in the frequency band 10 - 30 MHz. All bursts were always observed against a background of other solar radio activity such as type III and IIIb bursts, type III-like bursts, drift pairs and spikes. Moreover, S-bursts were observed during days when the active region was situated near the central meridian. Characteristic durations of S-bursts were about 0.35 and 0.4 - 0.6 s for the May and July storms, respectively. For the first time, we found that the instantaneous frequency width of S-bursts increased with frequency linearly. The dependence of drift rates on frequency followed the McConnell dependence derived for higher frequencies. We propose a model of S-bursts based on the assumption that these bursts are generated due to the confluence of Langmuir waves with fast magnetosonic waves, whose phase and group velocities are equal.

  1. Delivering Agents Locally into Articular Cartilage by Intense MHz Ultrasound

    PubMed Central

    Nieminen, Heikki J.; Ylitalo, Tuomo; Suuronen, Jussi-Petteri; Rahunen, Krista; Salmi, Ari; Saarakkala, Simo; Serimaa, Ritva; Hæggström, Edward

    2015-01-01

    There is no cure for osteoarthritis. Current drug delivery relies on systemic delivery or injections into the joint. Because articular cartilage (AC) degeneration can be local and drug exposure outside the lesion can cause adverse effects, localized drug delivery could permit new drug treatment strategies. We investigated whether intense megahertz ultrasound (frequency: 1.138 MHz, peak positive pressure: 2.7 MPa, Ispta: 5 W/cm2, beam width: 5.7 mm at −6 dB, duty cycle: 5%, pulse repetition frequency: 285 Hz, mechanical index: 1.1) can deliver agents into AC without damaging it. Using ultrasound, we delivered a drug surrogate down to a depth corresponding to 53% depth of the AC thickness without causing histologically detectable damage to the AC. This may be important because early osteoarthritis typically exhibits histopathologic changes in the superficial AC. In conclusion, we identify intense megahertz ultrasound as a technique that potentially enables localized non-destructive delivery of osteoarthritis drugs or drug carriers into articular cartilage. PMID:25922135

  2. 50 MHz dual-mode buck DC—DC converter

    NASA Astrophysics Data System (ADS)

    Zhang, Zhang; Xing, Wang; Wencheng, Yu; Ye, Tan; Yizhong, Yang; Guangjun, Xie

    2016-08-01

    A 50 MHz 1.8/0.9 V dual-mode buck DC—DC converter is proposed in this paper. A dual-mode control for high-frequency DC—DC converter is presented to enhance the conversion efficiency of light-load in this paper. A novel zero-crossing detector is proposed to shut down synchronous rectification transistor NMOS when the inductor crosses zero, which can decrease the power loss caused by reverse current and the trip point is adjusted by regulating IBIAS (BIAS current). A new logic control for pulse-skipping modulation loop is also presented in this paper, which has advantages of simple structure and low power loss. The proposed converter is realized in SMIC 0.18 μm 1-poly 6-metal mixed signal CMOS process. With switching loss, conduction loss and reverse current related loss optimized, an efficiency of 57% is maintained at 10 mA, and a peak efficiency of 71% is measured at nominal operating conditions with a voltage conversion of 1.8 to 0.9 V. Project supported by the National Natural Science Foundation of China (Nos. 61404043, 61401137), the Key Laboratory of Infrared Imaging Material and Detectors, Shanghai Institute of Technical Physics, CAS (Nos. IIMDKFJJ-13-06, IIMDKFJJ-14-03), and the Fundamental Research Funds for the Central University (No. 2015HGZX0026).

  3. Dynamic Nuclear Polarization at 700 MHz/460 GHz

    PubMed Central

    Barnes, Alexander B.; Markhasin, Evgeny; Daviso, Eugenio; Michaelis, Vladimir K.; Nanni, Emilio A.; Jawla, Sudheer; Mena, Elijah L.; DeRocher, Ronald; Thakkar, Ajay; Woskov, Paul; Herzfeld, Judith; Temkin, Richard J.; Griffin, Robert G.

    2014-01-01

    We describe the design and implementation of the instrumentation required to perform DNP-NMR at higher field strengths than previously demonstrated, and report the first magic-angle spinning (MAS) DNP-NMR experiments performed at H/e frequencies of 700 MHz/460 GHz. The extension of DNP-NMR to 16.4 T has required the development of probe technology, cryogenics, gyrotrons, and microwave transmission lines. The probe contains a 460 GHz microwave channel, with corrugated waveguide, tapers, and miter-bends that couple microwave power to the sample. Experimental efficiency is increased by a cryogenic exchange system for 3.2 mm rotors within the 89 mm bore. Sample temperatures ≤85 K, resulting in improved DNP enhancements, are achieved by a novel heat exchanger design, stainless steel and brass vacuum jacketed transfer lines, and a bronze probe dewar. In addition, the heat exchanger is preceded with a nitrogen drying and generation system in series with a pre-cooling refrigerator. This reduces liquid nitrogen usage from >400 liters per day to <100 liters per day and allows for continuous (>7 days) cryogenic spinning without detrimental frost or ice formation. Initial enhancements, ε=−40, and a strong microwave power dependence suggests the possibility for considerable improvement. Finally, two-dimensional spectra of a model system demonstrate that the higher field provides excellent resolution, even in a glassy, cryoprotecting matrix. PMID:23000974

  4. RF breakdown of 805 MHz cavities in strong magnetic fields

    SciTech Connect

    Bowring, D.; Stratakis, D.; Kochemirovskiy, A.; Leonova, M.; Moretti, A.; Palmer, M.; Peterson, D.; Yonehara, K.; Freemire, B.; Lane, P.; Torun, Y.; Haase, A.

    2015-05-03

    Ionization cooling of intense muon beams requires the operation of high-gradient, normal-conducting RF structures in the presence of strong magnetic fields. We have measured the breakdown rate in several RF cavities operating at several frequencies. Cavities operating within solenoidal magnetic fields B > 0.25 T show an increased RF breakdown rate at lower gradients compared with similar operation when B = 0 T. Ultimately, this breakdown behavior limits the maximum safe operating gradient of the cavity. Beyond ionization cooling, this issue affects the design of photoinjectors and klystrons, among other applications. We have built an 805 MHz pillbox-type RF cavity to serve as an experimental testbed for this phenomenon. This cavity is designed to study the problem of RF breakdown in strong magnetic fields using various cavity materials and surface treatments, and with precise control over sources of systematic error. We present results from tests in which the cavity was run with all copper surfaces in a variety of magnetic fields.

  5. Modulation improvements in the 201 MHZ RF generators at LAMPF

    SciTech Connect

    Parsons, W M; Lyles, J T.M.; Harris, H W

    1992-01-01

    Radio-frequency generators, operating at 201 MHz, power the first four stages of the Los Alamos Meson Physics Facility (LAMPF) accelerator. Each generator consists of four stages of seriesconnected, vacuum-tube amplifiers. The modulation scheme for each stage is different. The fist amplifier is a grid-modulated tetrode that produces 500 W peak-power. The second amplifier is a drive-modulated tetrode that produces 5 kill peak-power. The third stage is a grid- and plate-modulated tetrode that produces 130 kill peak-power. The last stage is a plate-modulated triode that produces 2.5 MW peak power. A modernization program has been initiated to improve the reliability of each of these stages. The first two stages of each generator are being replaced with a single, drive-modulated, solid-state amplifier. Specifications for the amplifier design, and requirements for integration into the system are presented. The third stage will be converted to a drive-modulated system using the current tetrode. This modification involves the development of a 17-kV, 15-A switching supply to replace the present plate-modulator. Design requirements for this switching supply are presented. The final stage will remain plate-modulated but will contain a new driver unit for the modulator tube.

  6. 47 CFR 27.905 - 1670-1675 MHz 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 1670-1675 MHz service licenses subject to competitive bidding. 27.905 Section 27.905 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1670-1675 MHz Band § 27.905...

  7. 47 CFR 27.905 - 1670-1675 MHz service licenses subject to competitive bidding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false 1670-1675 MHz service licenses subject to competitive bidding. 27.905 Section 27.905 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1670-1675 MHz Band § 27.905...

  8. 47 CFR 27.905 - 1670-1675 MHz 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 1670-1675 MHz service licenses subject to competitive bidding. 27.905 Section 27.905 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1670-1675 MHz Band § 27.905...

  9. 47 CFR 27.1301 - Designated entities in the 600 MHz band.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Designated entities in the 600 MHz band. 27.1301 Section 27.1301 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 600 MHz Band § 27.1301 Designated entities in...

  10. 47 CFR 90.357 - Frequencies for LMS systems in the 902-928 MHz band.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies for LMS systems in the 902-928 MHz... SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Intelligent Transportation Systems Radio Service § 90.357 Frequencies for LMS systems in the 902-928 MHz band. (a) Multilateration LMS systems will...

  11. 47 CFR 90.18 - Public Safety 700 MHz Nationwide Broadband Network.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Network. 90.18 Section 90.18 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... 700 MHz Nationwide Broadband Network. The 763-768/793-798 MHz band is dedicated to a broadband public..., pursuant to a Network Sharing Agreement and such other agreements as the Commission may require....

  12. 47 CFR 22.413 - Developmental authorization of 72-76 MHz fixed transmitters.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the 72-76 MHz transmitter(s). (b) Exceptions. The FCC may grant a regular authorization in the Paging... case of the assignment of or a transfer of control of a regular authorization of a 72-76 MHz fixed station in the Paging and Radiotelephone Service, the FCC may grant such assignment or consent to...

  13. 47 CFR 90.801 - 900 MHz SMR spectrum subject to competitive bidding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false 900 MHz SMR spectrum subject to competitive bidding. 90.801 Section 90.801 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Specialized Mobile Radio Service § 90.801 900 MHz SMR spectrum subject to competitive bidding....

  14. 47 CFR 90.801 - 900 MHz SMR spectrum subject to competitive bidding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false 900 MHz SMR spectrum subject to competitive bidding. 90.801 Section 90.801 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Specialized Mobile Radio Service § 90.801 900 MHz SMR spectrum subject to competitive bidding....

  15. 47 CFR 90.801 - 900 MHz SMR spectrum subject to competitive bidding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false 900 MHz SMR spectrum subject to competitive bidding. 90.801 Section 90.801 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Specialized Mobile Radio Service § 90.801 900 MHz SMR spectrum subject to competitive bidding....

  16. 47 CFR 90.801 - 900 MHz SMR spectrum subject to competitive bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false 900 MHz SMR spectrum subject to competitive bidding. 90.801 Section 90.801 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Specialized Mobile Radio Service § 90.801 900 MHz SMR spectrum subject to competitive bidding....

  17. 47 CFR 90.801 - 900 MHz SMR spectrum subject to competitive bidding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false 900 MHz SMR spectrum subject to competitive bidding. 90.801 Section 90.801 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Specialized Mobile Radio Service § 90.801 900 MHz SMR spectrum subject to competitive bidding....

  18. VizieR Online Data Catalog: M51 total intensity image at 333MHz (Mulcahy+, 2016)

    NASA Astrophysics Data System (ADS)

    Mulcahy, D. D.; Fletcher, A.; Beck, R.; Mitra, D.; Scaife, A. M. M.

    2016-06-01

    Total intensity image M51 with the 325MHz receiver of the GMRT at 15-arcsec resolution. Only the upperband data was used and thus the central frequency is 333MHz. Full details of the observation,calibration and imaging can be seen in the paper. (2 data files).

  19. 47 CFR 87.199 - Special requirements for 406.0-406.1 MHz ELTs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of this standard can be inspected at the Federal... contain as an integral part a homing beacon operating only on 121.500 MHz that meets all the requirements... MHz homing beacon must have a continuous duty cycle that may be interrupted during the transmission...

  20. 47 CFR 87.199 - Special requirements for 406.0-406.1 MHz ELTs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of this standard can be inspected at the Federal... contain as an integral part a homing beacon operating only on 121.500 MHz that meets all the requirements... MHz homing beacon must have a continuous duty cycle that may be interrupted during the transmission...

  1. 47 CFR 87.199 - Special requirements for 406.0-406.1 MHz ELTs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of this standard can be inspected at the Federal... contain as an integral part a homing beacon operating only on 121.500 MHz that meets all the requirements... MHz homing beacon must have a continuous duty cycle that may be interrupted during the transmission...

  2. 47 CFR 87.199 - Special requirements for 406.0-406.1 MHz ELTs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of this standard can be inspected at the Federal... contain as an integral part a homing beacon operating only on 121.500 MHz that meets all the requirements... MHz homing beacon must have a continuous duty cycle that may be interrupted during the transmission...

  3. 47 CFR 27.1031 - Reimbursement obligation of licensees at 1995-2000 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... licensees at 1995-2000 MHz. A licensee in the 1995-2000 MHz band (Upper H Block) shall, within 30 days of... band, on a pro rata shared basis with other Upper H Block licensees as set forth in paragraphs (a... this spectrum cover, collectively, at least forty (40) percent of the nation's population, the...

  4. 77 FR 19575 - Promoting Interoperability in the 700 MHz Commercial Spectrum; Interoperability of Mobile User...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-02

    ... Mobile User Equipment Across Paired Commercial Spectrum Blocks in the 700 MHz Band AGENCY: Federal... MHz band and to encourage the efficient use of spectrum. DATES: Interested parties may file comments...), illustrated in the following figure, is comprised of 70 megahertz of commercial, non-guard band spectrum,...

  5. Implementation and evaluation of the new wind algorithm in NASA's 50 MHz doppler radar wind profiler

    NASA Technical Reports Server (NTRS)

    Taylor, Gregory E.; Manobianco, John T.; Schumann, Robin S.; Wheeler, Mark M.; Yersavich, Ann M.

    1993-01-01

    The purpose of this report is to document the Applied Meteorology Unit's implementation and evaluation of the wind algorithm developed by Marshall Space Flight Center (MSFC) on the data analysis processor (DAP) of NASA's 50 MHz doppler radar wind profiler (DRWP). The report also includes a summary of the 50 MHz DRWP characteristics and performance and a proposed concept of operations for the DRWP.

  6. 47 CFR 90.1408 - Organization and structure of the 700 MHz public/private partnership.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Organization and structure of the 700 MHz public/private partnership. 90.1408 Section 90.1408 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Partnership § 90.1408 Organization and structure of the 700 MHz public/private partnership. (a) The Upper...

  7. 47 CFR 27.905 - 1670-1675 MHz service licenses subject to competitive bidding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false 1670-1675 MHz service licenses subject to competitive bidding. 27.905 Section 27.905 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1670-1675 MHz Band § 27.905...

  8. 47 CFR 27.905 - 1670-1675 MHz service licenses subject to competitive bidding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false 1670-1675 MHz service licenses subject to competitive bidding. 27.905 Section 27.905 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1670-1675 MHz Band § 27.905...

  9. 47 CFR 80.303 - Watch on 156.800 MHz (Channel 16).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Watch on 156.800 MHz (Channel 16). 80.303... SERVICES STATIONS IN THE MARITIME SERVICES Safety Watch Requirements and Procedures Coast Station Safety Watches § 80.303 Watch on 156.800 MHz (Channel 16). (a) During its hours of operation, each coast...

  10. 47 CFR 80.303 - Watch on 156.800 MHz (Channel 16).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Watch on 156.800 MHz (Channel 16). 80.303... SERVICES STATIONS IN THE MARITIME SERVICES Safety Watch Requirements and Procedures Coast Station Safety Watches § 80.303 Watch on 156.800 MHz (Channel 16). (a) During its hours of operation, each coast...

  11. 47 CFR 80.303 - Watch on 156.800 MHz (Channel 16).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Watch on 156.800 MHz (Channel 16). 80.303... SERVICES STATIONS IN THE MARITIME SERVICES Safety Watch Requirements and Procedures Coast Station Safety Watches § 80.303 Watch on 156.800 MHz (Channel 16). (a) During its hours of operation, each coast...

  12. 47 CFR 80.303 - Watch on 156.800 MHz (Channel 16).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Watch on 156.800 MHz (Channel 16). 80.303... SERVICES STATIONS IN THE MARITIME SERVICES Safety Watch Requirements and Procedures Coast Station Safety Watches § 80.303 Watch on 156.800 MHz (Channel 16). (a) During its hours of operation, each coast...

  13. 47 CFR 80.303 - Watch on 156.800 MHz (Channel 16).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Watch on 156.800 MHz (Channel 16). 80.303... SERVICES STATIONS IN THE MARITIME SERVICES Safety Watch Requirements and Procedures Coast Station Safety Watches § 80.303 Watch on 156.800 MHz (Channel 16). (a) During its hours of operation, each coast...

  14. 47 CFR 95.627 - MedRadio transmitters in the 401-406 MHz band.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false MedRadio transmitters in the 401-406 MHz band... SPECIAL RADIO SERVICES PERSONAL RADIO SERVICES Technical Regulations Technical Standards § 95.627 MedRadio transmitters in the 401-406 MHz band. The following provisions apply only to MedRadio transmitters operating...

  15. 47 CFR 90.18 - Public Safety 700 MHz Nationwide Broadband Network.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Network. 90.18 Section 90.18 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... 700 MHz Nationwide Broadband Network. The 763-768/793-798 MHz band is dedicated to a broadband public..., pursuant to a Network Sharing Agreement and such other agreements as the Commission may require....

  16. 47 CFR 22.599 - Assignment of 72-76 MHz channels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... to the following conditions: (a) Assignments of 72-76 MHz channels for use within 129 kilometers (80... immediately discontinued. (b) 72-76 MHz channels may be assigned for use within 16 kilometers (10 miles) of a... to § 22.413. However, for use within 50 meters (164 feet) of a TV station transmitting on TV...

  17. 47 CFR 22.599 - Assignment of 72-76 MHz channels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... to the following conditions: (a) Assignments of 72-76 MHz channels for use within 129 kilometers (80... immediately discontinued. (b) 72-76 MHz channels may be assigned for use within 16 kilometers (10 miles) of a... to § 22.413. However, for use within 50 meters (164 feet) of a TV station transmitting on TV...

  18. 47 CFR 22.599 - Assignment of 72-76 MHz channels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... to the following conditions: (a) Assignments of 72-76 MHz channels for use within 129 kilometers (80... immediately discontinued. (b) 72-76 MHz channels may be assigned for use within 16 kilometers (10 miles) of a... to § 22.413. However, for use within 50 meters (164 feet) of a TV station transmitting on TV...

  19. Influence of 400, 900, and 1900 MHz electromagnetic fields on Lemna minor growth and peroxidase activity.

    PubMed

    Tkalec, Mirta; Malarić, Kresimir; Pevalek-Kozlina, Branka

    2005-04-01

    Increased use of radio and microwave frequencies requires investigations of their effects on living organisms. Duckweed (Lemna minor L.) has been commonly used as a model plant for environmental monitoring. In the present study, duckweed growth and peroxidase activity was evaluated after exposure in a Gigahertz Transversal Electromagnetic (GTEM) cell to electric fields of frequencies 400, 900, and 1900 MHz. The growth of plants exposed for 2 h to the 23 V/m electric field of 900 MHz significantly decreased in comparison with the control, while an electric field of the same strength but at 400 MHz did not have such effect. A modulated field at 900 MHz strongly inhibited the growth, while at 400 MHz modulation did not influence the growth significantly. At both frequencies a longer exposure mostly decreased the growth and the highest electric field (390 V/m) strongly inhibited the growth. Exposure of plants to lower field strength (10 V/m) for 14 h caused significant decrease at 400 and 1900 MHz while 900 MHz did not influence the growth. Peroxidase activity in exposed plants varied, depending on the exposure characteristics. Observed changes were mostly small, except in plants exposed for 2 h to 41 V/m at 900 MHz where a significant increase (41%) was found. Our results suggest that investigated electromagnetic fields (EMFs) might influence plant growth and, to some extent, peroxidase activity. However, the effects of EMFs strongly depended on the characteristics of the field exposure. PMID:15768427

  20. 47 CFR 95.627 - MedRadio transmitters in the 401-406 MHz band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false MedRadio transmitters in the 401-406 MHz band... SPECIAL RADIO SERVICES PERSONAL RADIO SERVICES Technical Regulations Technical Standards § 95.627 MedRadio transmitters in the 401-406 MHz band. The following provisions apply only to MedRadio transmitters operating...

  1. Results of Q Disease Tests With 350-MHz Spoke Cavities

    NASA Astrophysics Data System (ADS)

    Tajima, Tsuyoshi; Edwards, Randy L.; Krawczyk, Frank L.; Liu, Jian-Fei; Schrage, Dale L.; Shapiro, Alan H.

    2003-07-01

    Spoke cavities have been developed at LANL for an accelerator-driven nuclear waste transmutation system. One of the most important issues for this development is how we can build and operate the accelerator at minimum costs. It would save a significant amount of money if we do not need to heat treat the cavity at high temperatures to avoid Q disease. This motivated us to check to see if Q disease occurs with 350-MHz spoke cavities. We have tested 3 cavities, ANL, LANL/EZ02 and LANL/EZ01 so far. The ANL cavity was made of RRR˜150 and the LANL cavities were made of RRR˜250 niobium. The ANL cavity was chemically polished 98 microns at LANL with a standard buffered chemical polishing (BCP) solution, i.e., HF:HNO3:H3PO4=1:1:2 by volume, at 14 - 18 °C. We did not see any Q degradation after holding the cavity at 100 - 102 K for 13 hours or at 100 - 142 K for 86 hours. This cavity was unintentionally baked at >200 °C under poor vacuum, which may have caused thicker oxide layer that prevent the Q disease from occurring as well as due to lower RRR. The LANL/EZ02 and LANL/EZ01 cavities were polished 150 microns with standard BCP solution at <15 °C. The LANL/EZ02 cavity showed a ˜50 % Q degradation after holding the cavity at 100 - 132 K for 61 hours. More systematic tests with LANL/EZ01 to determine the dangerous temperature range precisely are under way by changing the holding temperature every 10 K. The detail of the results will be presented here.

  2. Antiproton acceleration in the Fermilab Main Injector using 2.5 MHz (H=28) and 53 MHz (H=588) rf systems

    SciTech Connect

    Vincent Wu et al.

    2003-06-10

    During the Run II era at Fermilab, the Recycler stores antiprotons at 8 GeV and the Main Injector accelerates the antiprotons and the protons from 8 GeV to 150 GeV for Tevatron injection. The Recycler injects antiprotons to the Main Injector in 2.5 MHz rf buckets. This report presents an acceleration scheme for the antiprotons that involves a slow ramp with initial 2.5 MHz acceleration and subsequent fast acceleration with 53 MHz rf system. Beam acceleration and rf manipulation with space charge and beam loading effects are simulated using the longitudinal simulation code ESME. Simulation suggests that one can expect about 15% emittance growth for the entire acceleration cycle with beam loading compensations. Preliminary experimental results with proton beam will also be presented.

  3. R&D ERL: 5 Cell 704 MHz SRF Cavity

    SciTech Connect

    Burrill, A.

    2010-01-01

    One of the key components for the superconducting RF Energy Recovery Linac, (ERL) under development in the Collider Accelerator Department at Brookhaven National Laboratory, is the Linac cavity and cryomodule. The cavity is a 5 cell accelerating cavity designed to operate at 703.75 MHz, and to accelerate 2 MeV electrons from the photoinjector up to 15-20 MeV, allow them to make a single pass around the ERL loop and then decelerate them back down to 2 MeV prior to sending them to the beam dump. This cavity was designed by Rama Calaga and Ilan Ben-Zvi at BNL and fabricated by Advanced Energy Systems in Medford, NY. The cavity was then delivered to Thomas Jefferson Laboratory in VA for chemical processing, testing and assembly of the hermetic string assembly suitable for shipment back to BNL. Once at BNL it was built into a complete cryomodule, installed in the ERL test facility and commissioned. This paper will review the key components of the cavity and cryomodule and discuss the present status of the cryomodule commissioning. The BNL 5 cell accelerating cavity has been designed for use in our high average current Energy Recovery Linac, a proof of principle machine to demonstrate key components necessary for the future upgrades to RHIC as well as applications for future ampere class high current, high brightness ERL programs. The cavity has been tested at greater than 20 MV/m with a Q{sub 0} of 1e{sup 10}, meeting the design specifications for use at full energy in the ERL. This paper will review the cavity design and specifications as well as the RF measurements that have been made both in the VTA at Jefferson Lab as well as during the commissioning in the ERL test cave at BNL. Finally the future plan for cavity testing and measurements prior to its use in ERL operations will be reviewed. The general physics parameters for the cavity can be found in table 1, and the reader is referred to Rama Calaga's Thesis for a much more detailed review of the cavity geometry

  4. 47 CFR 90.1432 - Conditions for waiver to allow limited and temporary wideband operations in the 700 MHz public...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... temporary wideband operations in the 700 MHz public safety spectrum. 90.1432 Section 90.1432... and temporary wideband operations in the 700 MHz public safety spectrum. (a) Wideband operations in the 700 MHz Public Safety spectrum. Wideband operations are prohibited in the public safety...

  5. 75 FR 3639 - Revisions to Rules Authorizing the Operation of Low Power Auxiliary Stations in the 698-806 MHz...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-22

    ... 698-806 MHz Band; Public Interest Spectrum Coalition, Petition for Rulemaking Regarding Low Power... Power Auxiliary Stations in the 698-806 MHz Band; Public Interest Spectrum Coalition, Petition for... Operation of Low Power Auxiliary Stations in the 698-806 MHz Band; Public Interest Spectrum...

  6. 75 FR 9113 - Revisions to Rules Authorizing the Operation of Low Power Auxiliary Stations in the 698-806 MHz...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-01

    ... Stations in the 698-806 MHz Band; Public Interest Spectrum Coalition, Petition for Rulemaking Regarding Low... Authorizing the Operation of Low Power Auxiliary Stations in the 698-806 MHz Band; Public Interest Spectrum... Auxiliary Stations in the 698-806 MHz Band; Public Interest Spectrum Coalition, Petition for...

  7. 47 CFR 27.1303 - Upper 700 MHz D Block license conditions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 700 MHz Public/Private Partnership § 27.1303 Upper... Block licensee shall have the exclusive right to build and operate the shared wireless broadband...

  8. 47 CFR 27.1303 - Upper 700 MHz D Block license conditions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 700 MHz Public/Private Partnership § 27.1303 Upper... Block licensee shall have the exclusive right to build and operate the shared wireless broadband...

  9. 47 CFR 27.1308 - Organization and structure of the 700 MHz public/private partnership.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 700 MHz Public/Private... require or allow shall have the obligation to build out the Shared Wireless Broadband Network, as...

  10. 47 CFR 27.1308 - Organization and structure of the 700 MHz public/private partnership.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 700 MHz Public/Private... require or allow shall have the obligation to build out the Shared Wireless Broadband Network, as...

  11. 78 FR 42701 - Improving Public Safety Communications in the 800 MHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-17

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 90 Improving Public Safety Communications in the 800 MHz Band AGENCY: Federal Communications Commission. ACTION: Final rule. SUMMARY: In this document, the Federal Communications...

  12. Specific absorption rate in models of man and monkey at 225 and 2000 MHz

    SciTech Connect

    Olsen, R.G.; Griner, T.A.

    1987-01-01

    Full-size models of a man and a rhesus monkey were exposed to radiofrequency (RF) radiation at 225 MHz. The model of man was also exposed to 2000 MHz. Specific absorption rates (SARs) were measured in partial-body sections, such as the arms, legs, etc., using gradient-layer calorimeters. Also, front-surface thermographic images were obtained to qualitatively show the heating patterns. For all of the configurations used, the SAR in the limbs was much higher than in the torso. Agreement (whole-body SARs) with spheroidal models was better for both models at 225 MHz than at 2000 MHz. These results indicate that in the frequency range two orders of magnitude above whole-body resonance, SAR in the limbs significantly contributes to the whole-body average SAR.

  13. 47 CFR 27.1308 - Organization and structure of the 700 MHz public/private partnership.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 700 MHz Public/Private... require or allow shall have the obligation to build out the Shared Wireless Broadband Network, as...

  14. 76 FR 62309 - Implementing a Nationwide, Broadband, Interoperable Public Safety Network in the 700 MHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-07

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Chapter I Implementing a Nationwide, Broadband, Interoperable Public Safety Network in the 700 MHz Band AGENCY: Federal Communications Commission. ACTION: Final rule. SUMMARY: In this...

  15. DSN 64-meter antenna L-band (1668-MHz) microwave system performance overview

    NASA Technical Reports Server (NTRS)

    Withington, J.

    1988-01-01

    In 1985, L-band (1668 MHz) receive-only feed systems were installed on the three Deep Space Network 64 meter antennas to provide tracking support for two non-NASA spacecraft. The specifications, design approach, and operational test results are presented. The L-band microwave system met all of its tracking goals and is currently being upgraded to include a C-band (5000 MHz) uplink.

  16. 78 FR 23855 - Improving Public Safety Communications in the 800 MHz Band; New 800 MHz Band Plan for U.S.-Mexico...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-23

    ... for the National Public Safety Planning Advisory Committee (NPCPAC) Regions bordering Mexico, 77 FR...: This document establishes a reconfigured 800 MHz band plan for the National Public Safety Planning Advisory Committee Regions bordering Mexico. This action is necessary to meet the Commission's goals...

  17. 47 CFR 90.259 - Assignment and use of frequencies in the bands 216-220 MHz and 1427-1432 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... power is 2 watts. The maximum antenna height above average terrain (HAAT) is 152 m (500 feet). (5) In... of Charles City, Chesterfield, Dinwiddie, Goochland, Hanover, Henrico, Isle of Wight, James City, New... locations, secondary operations are performed in the 1427-1429.5 MHz band. The maximum power is 1 watt...

  18. 47 CFR 90.259 - Assignment and use of frequencies in the bands 216-220 MHz and 1427-1432 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... power is 2 watts. The maximum antenna height above average terrain (HAAT) is 152 m (500 feet). (5) In... of Charles City, Chesterfield, Dinwiddie, Goochland, Hanover, Henrico, Isle of Wight, James City, New... locations, secondary operations are performed in the 1427-1429.5 MHz band. The maximum power is 1 watt...

  19. 47 CFR 90.259 - Assignment and use of frequencies in the bands 216-220 MHz and 1427-1432 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... power is 2 watts. The maximum antenna height above average terrain (HAAT) is 152 m (500 feet). (5) In... of Charles City, Chesterfield, Dinwiddie, Goochland, Hanover, Henrico, Isle of Wight, James City, New... locations, secondary operations are performed in the 1427-1429.5 MHz band. The maximum power is 1 watt...

  20. 47 CFR 90.259 - Assignment and use of frequencies in the bands 216-220 MHz and 1427-1432 MHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... power is 2 watts. The maximum antenna height above average terrain (HAAT) is 152 m (500 feet). (5) In... of Charles City, Chesterfield, Dinwiddie, Goochland, Hanover, Henrico, Isle of Wight, James City, New... locations, secondary operations are performed in the 1427-1429.5 MHz band. The maximum power is 1 watt...

  1. 47 CFR 101.82 - Reimbursement and relocation expenses in the 2110-2150 MHz and 2160-2200 MHz bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... between AWS and MSS (space-to-Earth downlink). Whenever an ET licensee (AWS or Mobile Satellite Service for space-to-Earth downlink in the 2130-2150 or 2180-2200 MHz bands) relocates an incumbent paired... section from any other AWS licensee or MSS space-to-Earth downlink operator which would have been...

  2. 47 CFR 101.82 - Reimbursement and relocation expenses in the 2110-2150 MHz and 2160-2200 MHz bands.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... between AWS and MSS (space-to-Earth downlink). Whenever an ET licensee (AWS or Mobile Satellite Service for space-to-Earth downlink in the 2130-2150 or 2180-2200 MHz bands) relocates an incumbent paired... section from any other AWS licensee or MSS space-to-Earth downlink operator which would have been...

  3. 47 CFR 101.82 - Reimbursement and relocation expenses in the 2110-2150 MHz and 2160-2200 MHz bands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... between AWS and MSS (space-to-Earth downlink). Whenever an ET licensee (AWS or Mobile Satellite Service for space-to-Earth downlink in the 2130-2150 or 2180-2200 MHz bands) relocates an incumbent paired... section from any other AWS licensee or MSS space-to-Earth downlink operator which would have been...

  4. Detection of Pulsed Emission from the Millisecond Pulsar PSR J2145-0750 Below 100 MHz

    NASA Astrophysics Data System (ADS)

    Taylor, Gregory B.; Dowell, J.; Wavelength Array, Long

    2014-01-01

    Millisecond pulsars (MPSs) are distinguished from normal pulsars by faster rotation periods, weaker magnetic fields, and flux density spectra that are well fit by a single power law down to 100 MHz. Below 100 MHz some MSPs show a break in the power law, however, additional observations, particularly of the pulse profile, are needed in this frequency range to provide better constraints on emission mechanisms. The first station of the Long Wavelength Array, LWA1, is a low frequency telescope that is ideally suited to address these questions. We present recent results from LWA1 on the millisecond pulsar PSR J2145-0750. Using coherent dedispersion we detected pulsed emission between 37 and 85 MHz. From this we derive flux densities and pulse profiles at 41, 57, 65, 73, and 81 MHz. We find that the flux density spectrum of PSR J2145-0750 appears to flatten below 100 MHz relative to the spectral index of ~-1.6 found in the literature. We also find that the pulse profile shows little evolution over this frequency range and is similar to profiles found at 102 MHz. We also discuss the prospects for precision dispersion measure monitoring at these frequencies. Construction of the LWA has been supported by the Office of Naval Research under Contract N00014-07-C-0147. Support for operations and continuing development of the LWA1 is provided by the National Science Foundation under grants AST-1139963 and AST-1139974 of the University Radio Observatory program.

  5. OBSERVATIONS OF CRAB GIANT PULSES IN 20-84 MHz USING LWA1

    SciTech Connect

    Ellingson, S. W.; Wolfe, C. N.; Clarke, T. E.; Hicks, B. C.; Wilson, T. L.; Craig, J.; Taylor, G. B.; Lazio, T. J. W.

    2013-05-10

    We report the detection and observed characteristics of giant pulses from the Crab Nebula pulsar (B0531+21) in four frequency bands covering 20-84 MHz using the recently completed Long Wavelength Array Station 1 (LWA1) radio telescope. In 10 hr of observations distributed over a 72 day period in fall of 2012, 33 giant pulses having peak flux densities between 400 Jy and 2000 Jy were detected. Twenty-two of these pulses were detected simultaneously in channels of 16 MHz bandwidth centered at 44 MHz, 60 MHz, and 76 MHz, including one pulse which was also detected in a channel centered at 28 MHz. We quantify statistics of pulse amplitude and pulse shape characteristics, including pulse broadening. Amplitude statistics are consistent with expectations based on extrapolations from previous work at higher and lower frequencies. Pulse broadening is found to be relatively high, but not significantly greater than expected. We present procedures that have been found to be effective for observing giant pulses in this frequency range.

  6. Search for 54-MHz Maser Emission from Interstellar Hydroxyl Using the Long Wavelength Array

    NASA Astrophysics Data System (ADS)

    Hoffman, Ian M.

    2015-01-01

    We present the results of an observational campaign using the Long Wavelength Array (LWA). The level splitting of the rotational ground state of the hydroxyl (OH) molecule gives rise to the four familiar 1.7-GHz (18-cm) transitions by which OH is known in the interstellar medium. There are also two magnetic-dipole transitions among these states at frequencies of 53.2 MHz and 55.1 MHz. These 54-MHz transitions have never been detected astronomically. Because of the relative weakness of the magnetic-dipole radiative process, it is expected that only maser emission will generate a detectable 54-MHz signal. Many of the prevailing pumping models for 18-cm masers are also suggestive of population inversions of the 54-MHz transitions. We have targeted our search toward Galactic locations that are known to exhibit strong 1720-MHz maser emission from OH with the expectation that either of the 54-MHz transitions will also be overpopulated.Using the LWA station LWA1, we have searched the sources NGC 7538, G33.64-0.21, W75N, and Sgr A. For each target we employed 20 hours of integration time in beam-formed mode. We employed 1024 spectral channels in a 250-kHz observing band for each of the two transitions, resulting in a velocity resolution of approximately 1.4 km/s. We did not detect masers in either transition toward any of the sources. Previously reported observations of W75N using LOFAR also resulted in a non-detection; none of the other sources have been searched previously for either 53.2- or 55.1-MHz emission. We discuss the results in the context of previous and ongoing searches for 54-MHz emission.This work is supported by Wittenberg University through the Physics Department. Construction of the LWA has been supported by the Office of Naval Research under Contract N00014-07-C-0147. Support for operations and continuing development of the LWA1 is provided by the National Science Foundation under grants AST-1139963 and AST-1139974 of the University Radio Observatory

  7. 27.12 MHz Radiofrequency Ablation for Benign Cutaneous Lesions

    PubMed Central

    Kim, Dong Hyun; Hyun, Dong Ju; Piquette, Raymonde; Beaumont, Clément; Germain, Lucie; Larouche, Danielle

    2016-01-01

    As surgical and/or ablative modalities, radiofrequency (RF) has been known to produce good clinical outcomes in dermatology. Recently, 27.12 MHz RF has been introduced and has several advantages over conventional 4 or 6 MHz in terms of the precise ablation and lesser pain perception. We aimed to evaluate the clinical efficacy and safety of 27.12 MHz RF for the treatment of benign cutaneous lesions. Twenty female patient subjects were enrolled. Digital photography and a USB microscope camera were used to monitor the clinical results before one session of treatment with 27.12 MHz RF and after 1 and 3 weeks. Treated lesions included telangiectasias, cherry and spider angiomas, skin tags, seborrheic keratoses, lentigo, milium, dilated pore, acne, piercing hole, and one case of neurofibroma. For vascular lesions, clinical results were excellent for 33.3%, good for 44.4%, moderate for 11.1%, and poor for 11.1%. For nonvascular lesions (epidermal lesions and other benign cutaneous lesions), clinical results were excellent for 48.3%, good for 45.2%, moderate for 3.2%, and poor for 3.2%. No serious adverse events were observed. Mild adverse events reported were slight erythema, scale, and crust. The 27.12 MHz RF treatment of benign vascular and nonvascular lesions appears safe and effective after 3 weeks of follow-up. PMID:27127789

  8. 27.12 MHz Radiofrequency Ablation for Benign Cutaneous Lesions.

    PubMed

    Kim, Dong Hyun; Hyun, Dong Ju; Piquette, Raymonde; Beaumont, Clément; Germain, Lucie; Larouche, Danielle

    2016-01-01

    As surgical and/or ablative modalities, radiofrequency (RF) has been known to produce good clinical outcomes in dermatology. Recently, 27.12 MHz RF has been introduced and has several advantages over conventional 4 or 6 MHz in terms of the precise ablation and lesser pain perception. We aimed to evaluate the clinical efficacy and safety of 27.12 MHz RF for the treatment of benign cutaneous lesions. Twenty female patient subjects were enrolled. Digital photography and a USB microscope camera were used to monitor the clinical results before one session of treatment with 27.12 MHz RF and after 1 and 3 weeks. Treated lesions included telangiectasias, cherry and spider angiomas, skin tags, seborrheic keratoses, lentigo, milium, dilated pore, acne, piercing hole, and one case of neurofibroma. For vascular lesions, clinical results were excellent for 33.3%, good for 44.4%, moderate for 11.1%, and poor for 11.1%. For nonvascular lesions (epidermal lesions and other benign cutaneous lesions), clinical results were excellent for 48.3%, good for 45.2%, moderate for 3.2%, and poor for 3.2%. No serious adverse events were observed. Mild adverse events reported were slight erythema, scale, and crust. The 27.12 MHz RF treatment of benign vascular and nonvascular lesions appears safe and effective after 3 weeks of follow-up. PMID:27127789

  9. Dielectric spectroscopy of fresh fruit and vegetable tissues from 10 to 1800 MHz.

    PubMed

    Nelson, Stuart O

    2005-01-01

    Dielectric spectroscopy data from measurements on tissue samples of nine fresh fruits and vegetables were used to study their dielectric behavior over the frequency range from 10 MHz to 1.8 GHz at 5 to 65 degrees C. Dielectric constant and loss-factor data are presented graphically for apple, avocado, banana, cantaloupe, carrot, cucumber, grape, orange, and potato, showing dielectric constants ranging from values of several hundred at 10 MHz to less than 100 at 1.8 GHz and loss factors on the order of one thousand at 10 MHz to less than 20 at 1.8 GHz. The dielectric loss factor increased consistently with increasing temperature at frequencies below 1 GHz. The dielectric constant increased with temperature at lower frequencies, but it decreased with temperature at the higher frequencies. This reversal of the sign of the temperature coefficient occurred at some point in the frequency range between 20 and 120 MHz where the temperature dependence of the dielectric constant was zero. At frequencies below this point, ionic conduction dominates the dielectric behavior, but above that point dipolar relaxation appears to control the behavior. Multiple linear regression provided equations for calculation of the loss factor in the frequency range from 10 to 300 MHz at temperatures from 5 to 65 degrees C. The data provide new information useful in understanding dielectric heating behavior and evaluating dielectric properties of such agricultural products for quality sensing applications.

  10. A three-month comparison of hourly winds and temperatures from co-located 50-MHz and 915-MHz RASS profilers

    SciTech Connect

    Coulter, R.L.; Holdridge, D.J.

    1995-06-01

    The Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Program has operated a 915-MHz and a 50-MHz radar wind profiler (boundary layer profiler (BLP) and tropospheric profiler (TP), respectively], each coupled with a Radio Acoustic Sounding System (RASS) since April 1994 at its Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) central facility in north central Oklahoma. The dual system is designed to provide continuous wind profiles from near the surface to 12 km or more and virtual temperature profiles from near the surface to 6 km. Because the BLP has a larger antenna than many other 915-MHz systems, the wind profiles sampled by the two systems overlap between 1.5 km and 5.5 km. The two systems are adjacent, so the wind profilers sample almost identical air masses in their overlap region during the averaging period. Nevertheless, the two RASS systems can be compared, and methods can be devised to estimate the temperature profile in the inaccessible region. Data used in all comparisons and calculations discussed below are consensus-averaged values supplied by the profiler software. Although the spectra and moments from the data are available, they were not accessed for this analysis.

  11. Report on BIPM/CIPM key comparison CCAUV.U-K4: absolute calibration of medical hydrophones in the frequency range 0.5 MHz to 20 MHz

    NASA Astrophysics Data System (ADS)

    Rajagopal, S.; Fury, C. R.; Zeqiri, B.; Brandt, M.; Wilkens, V.; Koch, C.; Matsuda, Y.; Yoshioka, M.; Ping, Y.; Yan, Z.; Wenping, B.; Costa-Felix, R. P. B.; Oliveira, E. G.

    2016-01-01

    The key compariosn CCAUV.U-K4 involved measurement of end-of-cable loaded sensitivity in units of volts/pascal of two travelling standards, 1 mm element diamater medical hydrophones at medical ultrasound frequencies. This is a repetition of key comparison CCAUV.U-K2 but the scope has been extended upwards to 20 MHz and downwards to 0.5 MHz. The reduction in the lower frequency provided an overlap with the underwater acoustics key comparison CCAUV.W-K1 which covers the range 1 kHz to 0.5 MHz. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCAUV, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  12. Temperate zone sporadic-E maps /f/0/E/s/ greater than 7 MHz/

    NASA Technical Reports Server (NTRS)

    Smith, E. K.

    1978-01-01

    Three maps are presented of f(0) sporadic-E greater than 7 MHz for temperate zones. During map preparation it was assumed that: (1) the geographical area would be between plus and minus 60 deg geomagnetic latitude, excluding the equatorial zone, (2) the maps would be for f(0) sporadic-E greater than 7 MHz, (3) sunspot cycle variation would be ignored, (4) one map would represent the peak sporadic-E period with a discontinuity at the geographic equator, (5) one map would represent non-peak periods with a discontinuity at the geographic equator, (6) one map would represent all twelve months with no equatorial discontinuity, and (7) previously determined coefficients for median and upper decile f(0) sporadic-E would be extrapolated to 7 MHz.

  13. A low-loss linear analog phase modulator for 8415 MHz transponder application

    NASA Technical Reports Server (NTRS)

    Mysoor, N.

    1989-01-01

    A breadboard single-section low-loss analog phase modulator with good thermal stability for a spacecraft transponder application has been analyzed, fabricated, and evaluated. A linear phase shift of 70 degrees with a linearity tolerance of plus or minus 7 percent was measured for this modulator from 8257 to 8634 MHz over the temperature range -20 C to 75 C. The measured insertion loss and the static delay variation with temperature were within 2 plus or minus 0.3 dB and 0.16 ps/C, respectively. Four sections will be cascaded to provide the X-band (8415 MHz) phase modulator. The generic modulator design can also be utilized at 7950 to 8075 MHz followed by X4 multiplication to provide modulation of a Ka-band downlink signal.

  14. Theoretical and experimental analysis of a piezoelectric plate connected to a negative capacitance at MHz frequencies

    NASA Astrophysics Data System (ADS)

    Mansoura, S. A.; Benard, P.; Morvan, B.; Maréchal, P.; Hladky-Hennion, A.-C.; Dubus, B.

    2015-11-01

    In this paper, a theoretical and experimental study of the electric impedance of a piezoelectric plate connected to a negative capacitance is performed in the MHz frequency range. The negative capacitance is realized with a circuit using current conveyors (CCII+). This circuit allows us to achieve important values of negative capacitance, of the same order of the static capacitance of the piezoelectric plate studied. Mason’s model is considered for the theoretical characterization of the piezoelectric plate connected to the negative capacitance circuit. The experimental results show a large tunability of the frequency of the piezoelectric parallel resonance over a range of 1.1 MHz to 1.28 MHz. Moreover, according to the value of the negative capacitance, the effective electromechanical coupling factor of the piezoelectric plate is evaluated. With a very good agreement with the theoretical estimation, an increase of approximately 50% of the effective electromechanical coupling factor is experimentally measured.

  15. IBS and expected luminosity performance for RHIC beams at top energy with 56 MHz SRF cavity

    SciTech Connect

    Fedotov,A.

    2008-10-01

    The purpose of RF system in RHIC is to capture injected bunches, accelerate them to the top energy, and store bunches at the top energy for many hours. The accelerating RF system operates at harmonic number h=360 of the particle revolution frequency f=78.196 kHz, which corresponds to 28.15MHz. The storage RF system accepts the shortened bunches at top energy and provides longitudinal focusing to keep these bunches short during the store time (collision mode). The storage system operates at harmonic number h=7x360=2520, which corresponds to an RF frequency of 197.05 MHz [1]. Recently, an upgrade of storage RF system with a superconducting 56 MHz cavity was proposed [2]. This upgrade will provide significant increase in the acceptance of storage RF bucket. Presently, the short bunch length for collisions is obtained via RF gymnastics with bunch rotation (called re-bucketing), because the length of 197MHz bucket of 5 nsec is too short to accommodate long bunches otherwise. However, due to bucket non-linearity and hardware complications some increase in the longitudinal emittance occurs during re-bucketing. The 56MHz cavity will produce sufficiently short bunches which would allow one to operate without re-bucketing procedure. This Note summarizes simulation of beam evolution due to Intra-beam scattering (IBS) for beam parameters expected with the 56 MHz SRF cavity upgrade. Expected luminosity improvement is shown both for Au ions at 100 GeV/nucleon and for protons at 250 GeV.

  16. Occupancy of the radio frequency spectrum in the 16-23 MHz band

    NASA Technical Reports Server (NTRS)

    Ashkaliyev, Y. F.; Bocharov, V. I.

    1972-01-01

    Measurement results are presented for actual utilization of the short wave frequency band, obtained by continuous registration of the number of radio stations in the 16-23 MHz band over an annual cycle (1965). It is shown that there is a relation between the number of radio stations and the variations of MUF-F2. During years of minimum solar activity and at night, segments free of radio stations operating by normal reflection, can be selected in the 18-23-MHz band for ionospheric-scattering links.

  17. 47 CFR 27.1325 - Resolution of disputes after grant of the upper 700 MHz D block license.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 700 MHz Public/Private... Security Bureau and the Wireless Telecommunications Bureau are delegated joint responsibility...

  18. 47 CFR 27.1325 - Resolution of disputes after grant of the upper 700 MHz D block license.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 700 MHz Public/Private... Security Bureau and the Wireless Telecommunications Bureau are delegated joint responsibility...

  19. 47 CFR 27.303 - Upper 700 MHz commercial and public safety coordination zone.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Upper 700 MHz commercial and public safety coordination zone. 27.303 Section 27.303 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and...

  20. 47 CFR 27.65 - Acceptance of interference in 2000-2020 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Acceptance of interference in 2000-2020 MHz. 27.65 Section 27.65 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.65 Acceptance...

  1. 47 CFR 27.303 - Upper 700 MHz commercial and public safety coordination zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Upper 700 MHz commercial and public safety coordination zone. 27.303 Section 27.303 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and...

  2. 47 CFR 27.65 - Acceptance of interference in 2000-2020 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Acceptance of interference in 2000-2020 MHz. 27.65 Section 27.65 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.65 Acceptance...

  3. 75 FR 9210 - Wireless Telecommunications Bureau Seeks Comment on Petition for Rulemaking Regarding 700 MHz...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-01

    ... paper copies. See Electronic Filing of Documents in Rulemaking Proceedings, 63 FR 24121 (1998... COMMISSION Wireless Telecommunications Bureau Seeks Comment on Petition for Rulemaking Regarding 700 MHz Band...: Notice. SUMMARY: The Wireless Telecommunications Bureau seeks comment on a petition for rulemaking...

  4. 47 CFR 27.303 - Upper 700 MHz commercial and public safety coordination zone.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Upper 700 MHz commercial and public safety coordination zone. 27.303 Section 27.303 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and...

  5. 1800 MHz in vitro exposure device for experimental studies on the effects of mobile communication systems.

    PubMed

    Ardoino, L; Lopresto, V; Mancini, S; Pinto, R; Lovisolo, G A

    2004-01-01

    A wire patch cell (WPC) operating at the uplink frequency band of GSM 1800 MHz has been designed for in vitro experiments with the aim of investigating the possible biological effects of electromagnetic radiation associated with cellular phones. The 1800 MHz WPC design is a direct descendant of the original 900 MHz WPC introduced by Laval et al. This system provides a homogeneous specific absorption rate distribution, using four 3.5 cm petri dishes simultaneously. Numerical dosimetry has been performed using a commercial code (CST Microwave Studio), in order to evaluate accurately the efficiency of the structure (in terms of W kg(-1) per 1 W input power) and the distribution in the chosen biological target. The numerical results have been confirmed by experimental measurements performed by measuring thermal increase due to a high power impulse. The efficiency of the structure is 1.25 +/- 25% W kg(-1) per 1 W input power higher than the efficiency of the 900 MHz WPC. A few adjustments have been made in order to use the WPC in a standard incubator and to avoid thermal increases related to the radio frequency exposure. This exposure system has been adopted for the experiments scheduled in the RAMP and GUARD projects (VFPE).

  6. A GMRT survey of regions towards the Taurus molecular cloud at 323 and 608 MHz

    NASA Astrophysics Data System (ADS)

    Ainsworth, Rachael E.; Coughlan, Colm P.; Green, David A.; Scaife, Anna M. M.; Ray, Tom P.

    2016-11-01

    We present observations of three active sites of star formation in the Taurus molecular cloud complex taken at 323 and 608 MHz (90 and 50 cm, respectively) with the Giant Metrewave Radio Telescope (GMRT). Three pointings were observed as part of a pathfinder project, targeted at the young stellar objects (YSOs) L1551 IRS 5, T Tau and DG Tau (the results for these target sources were presented in a previous paper). In this paper, we search for other YSOs and present a survey comprising of all three fields; a by-product of the large instantaneous field of view of the GMRT. The resolution of the survey is of order 10 arcsec and the best rms noise at the centre of each pointing is of order 100 μJy beam-1 at 323 MHz and 50 μJy beam-1 at 608 MHz. We present a catalogue of 1815 and 687 field sources detected above 5σrms at 323 and 608 MHz, respectively. A total of 440 sources were detected at both frequencies, corresponding to a total unique source count of 2062 sources. We compare the results with previous surveys and showcase a sample of extended extragalactic objects. Although no further YSOs were detected in addition to the target YSOs based on our source-finding criteria, these data can be useful for targeted manual searches, studies of radio galaxies or to assist in the calibration of future observations with the Low-Frequency Array towards these regions.

  7. 47 CFR 27.1303 - Upper 700 MHz D Block license conditions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... as the Commission may require or allow, into the Network Sharing Agreement (NSA) that has been... the NSA and such other agreements as the Commission may require or allow. (c) The Upper 700 MHz D... specified in the NSA. (f) These conditions and requirements will apply to any related entities that...

  8. 78 FR 66298 - Promoting Interoperability in the 700 MHz Commercial Spectrum; Requests for Waiver and Extension...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-05

    ... telecommunications standards bodies that, among other things, establishes standards for different LTE band classes. A... cellular band. In the Interoperability NPRM, 77 FR 19575, April 2, 2012, the Commission discussed the... in the Lower 700 MHz Report and Order, 67 FR 5491, Feb. 6, 2002, it observed that the Lower 700...

  9. Concept em design of the 650 MHz cavities for the Project X

    SciTech Connect

    Yakovlev, V.; Champion, M.; Gonin, I.; Lunin, A.; Kazakov, S.; Khabiboulline, T.; Solyak, N.; Saini, A.; /Fermilab

    2011-03-01

    Concept of the 650 MHz cavities for the Project X is presented. Choice of the basic parameters, i.e., number of cells, geometrical {beta}, apertures, coupling coefficients, etc., is discussed. The cavity optimization criteria are formulated. Results of the RF design are presented for the cavities of both the low-energy and high-energy sections.

  10. 75 FR 33220 - Unlicensed Personal Communications Services Devices in the 1920-1930 MHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-11

    ... operating in the 1920-1930 MHz band (known as the UPCS band) to make more efficient use of this spectrum... UPCS band) to make more efficient use of this spectrum. The Commission takes this action in response to... more efficient use of the UPCS-band spectrum. Therefore, it proposes to modify the UPCS Rules as...

  11. 47 CFR 15.243 - Operation in the band 890-940 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Operation in the band 890-940 MHz. 15.243 Section 15.243 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.243 Operation in the band...

  12. 47 CFR 15.223 - Operation in the band 1.705-10 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Operation in the band 1.705-10 MHz. 15.223 Section 15.223 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.223 Operation in the band...

  13. 47 CFR 15.223 - Operation in the band 1.705-10 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Operation in the band 1.705-10 MHz. 15.223 Section 15.223 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.223 Operation in the band...

  14. 47 CFR 15.239 - Operation in the band 88-108 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.239 Operation in the band 88-108 MHz. (a) Emissions from the intentional radiator shall be confined within a band 200 kHz wide centered... the general radiated emission limits in § 15.209. (d) A custom built telemetry intentional...

  15. 47 CFR 15.241 - Operation in the band 174-216 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Operation in the band 174-216 MHz. 15.241 Section 15.241 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.241 Operation in the band...

  16. 47 CFR 15.227 - Operation within the band 26.96-27.28 MHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Operation within the band 26.96-27.28 MHz. 15.227 Section 15.227 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.227 Operation within the band...

  17. 47 CFR 15.225 - Operation within the band 13.110-14.010 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Operation within the band 13.110-14.010 MHz. 15.225 Section 15.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.225 Operation within the band...

  18. 47 CFR 15.229 - Operation within the band 40.66-40.70 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Operation within the band 40.66-40.70 MHz. 15.229 Section 15.229 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.229 Operation within the band...

  19. 47 CFR 15.239 - Operation in the band 88-108 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.239 Operation in the band 88-108 MHz. (a) Emissions from the intentional radiator shall be confined within a band 200 kHz wide centered... the general radiated emission limits in § 15.209. (d) A custom built telemetry intentional...

  20. 47 CFR 15.225 - Operation within the band 13.110-14.010 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Operation within the band 13.110-14.010 MHz. 15.225 Section 15.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.225 Operation within the band...

  1. 47 CFR 15.241 - Operation in the band 174-216 MHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Operation in the band 174-216 MHz. 15.241 Section 15.241 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.241 Operation in the band...

  2. 47 CFR 15.227 - Operation within the band 26.96-27.28 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Operation within the band 26.96-27.28 MHz. 15.227 Section 15.227 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.227 Operation within the band...

  3. 47 CFR 15.225 - Operation within the band 13.110-14.010 MHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Operation within the band 13.110-14.010 MHz. 15.225 Section 15.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.225 Operation within the band...

  4. 47 CFR 15.240 - Operation in the band 433.5-434.5 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Operation in the band 433.5-434.5 MHz. 15.240 Section 15.240 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.240 Operation in the band...

  5. 47 CFR 15.240 - Operation in the band 433.5-434.5 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Operation in the band 433.5-434.5 MHz. 15.240 Section 15.240 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.240 Operation in the band...

  6. 47 CFR 15.229 - Operation within the band 40.66-40.70 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Operation within the band 40.66-40.70 MHz. 15.229 Section 15.229 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.229 Operation within the band...

  7. 47 CFR 15.250 - Operation of wideband systems within the band 5925-7250 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Operation of wideband systems within the band 5925-7250 MHz. 15.250 Section 15.250 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.250...

  8. 47 CFR 15.223 - Operation in the band 1.705-10 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Operation in the band 1.705-10 MHz. 15.223 Section 15.223 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.223 Operation in the band...

  9. 47 CFR 15.227 - Operation within the band 26.96-27.28 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Operation within the band 26.96-27.28 MHz. 15.227 Section 15.227 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.227 Operation within the band...

  10. 47 CFR 15.241 - Operation in the band 174-216 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Operation in the band 174-216 MHz. 15.241 Section 15.241 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.241 Operation in the band...

  11. 47 CFR 15.240 - Operation in the band 433.5-434.5 MHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Operation in the band 433.5-434.5 MHz. 15.240 Section 15.240 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.240 Operation in the band...

  12. 47 CFR 15.223 - Operation in the band 1.705-10 MHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Operation in the band 1.705-10 MHz. 15.223 Section 15.223 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.223 Operation in the band...

  13. 47 CFR 15.239 - Operation in the band 88-108 MHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.239 Operation in the band 88-108 MHz. (a) Emissions from the intentional radiator shall be confined within a band 200 kHz wide centered... the general radiated emission limits in § 15.209. (d) A custom built telemetry intentional...

  14. 47 CFR 15.250 - Operation of wideband systems within the band 5925-7250 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Operation of wideband systems within the band 5925-7250 MHz. 15.250 Section 15.250 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.250...

  15. 47 CFR 15.229 - Operation within the band 40.66-40.70 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Operation within the band 40.66-40.70 MHz. 15.229 Section 15.229 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.229 Operation within the band...

  16. 47 CFR 15.241 - Operation in the band 174-216 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Operation in the band 174-216 MHz. 15.241 Section 15.241 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.241 Operation in the band...

  17. 47 CFR 15.223 - Operation in the band 1.705-10 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Operation in the band 1.705-10 MHz. 15.223 Section 15.223 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.223 Operation in the band...

  18. 47 CFR 15.243 - Operation in the band 890-940 MHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Operation in the band 890-940 MHz. 15.243 Section 15.243 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.243 Operation in the band...

  19. 47 CFR 15.243 - Operation in the band 890-940 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Operation in the band 890-940 MHz. 15.243 Section 15.243 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.243 Operation in the band...

  20. 47 CFR 15.225 - Operation within the band 13.110-14.010 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Operation within the band 13.110-14.010 MHz. 15.225 Section 15.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.225 Operation within the band...

  1. 47 CFR 15.229 - Operation within the band 40.66-40.70 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Operation within the band 40.66-40.70 MHz. 15.229 Section 15.229 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.229 Operation within the band...

  2. 47 CFR 15.250 - Operation of wideband systems within the band 5925-7250 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Operation of wideband systems within the band 5925-7250 MHz. 15.250 Section 15.250 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.250...

  3. 47 CFR 15.227 - Operation within the band 26.96-27.28 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Operation within the band 26.96-27.28 MHz. 15.227 Section 15.227 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.227 Operation within the band...

  4. 47 CFR 15.241 - Operation in the band 174-216 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Operation in the band 174-216 MHz. 15.241 Section 15.241 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.241 Operation in the band...

  5. 47 CFR 15.239 - Operation in the band 88-108 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.239 Operation in the band 88-108 MHz. (a) Emissions from the intentional radiator shall be confined within a band 200 kHz wide centered... the general radiated emission limits in § 15.209. (d) A custom built telemetry intentional...

  6. 47 CFR 15.227 - Operation within the band 26.96-27.28 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Operation within the band 26.96-27.28 MHz. 15.227 Section 15.227 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.227 Operation within the band...

  7. 47 CFR 15.239 - Operation in the band 88-108 MHz.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.239 Operation in the band 88-108 MHz. (a) Emissions from the intentional radiator shall be confined within a band 200 kHz wide centered... the general radiated emission limits in § 15.209. (d) A custom built telemetry intentional...

  8. 47 CFR 15.225 - Operation within the band 13.110-14.010 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Operation within the band 13.110-14.010 MHz. 15.225 Section 15.225 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.225 Operation within the band...

  9. 47 CFR 15.229 - Operation within the band 40.66-40.70 MHz.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Operation within the band 40.66-40.70 MHz. 15.229 Section 15.229 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.229 Operation within the band...

  10. 47 CFR 15.243 - Operation in the band 890-940 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Operation in the band 890-940 MHz. 15.243 Section 15.243 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.243 Operation in the band...

  11. 47 CFR 15.240 - Operation in the band 433.5-434.5 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Operation in the band 433.5-434.5 MHz. 15.240 Section 15.240 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.240 Operation in the band...

  12. Pilot observations at 74 MHz for global 21cm cosmology with the Parkes 64 m

    NASA Astrophysics Data System (ADS)

    Bannister, Keith; McConnell, David; Reynolds, John; Chippendale, Aaron; Landecker, Tom L.; Dunning, Alex

    2013-10-01

    We propose a single pilot observing session using the existing 74 MHz feed at Parkes to evaluate tools and techniques to optimise low frequency (44-88 MHz) observing. 1. A continuum map of the diffuse emission in the Southern sky at 74 MHz. Such a map would be of great help to single-dipole 21cm cosmology experiments, whose diffuse Galactic foregrounds are currently poorly constrained (Pritchard & Loeb, 2010b; de Oliveira-Costa et al., 2008). 2. A wideband (44-88 MHz) map of of the Southern sky, which can be used as a direct detection of the dark ages global signal. Recent theoretical work has shown that the Parkes aperture of 64 m is the optimal size for such a direct detection, which could be achieved at 25? in as little as 100 hrs of observing (Liu et al., 2012). After receiving a 4.1 grade in the previous round, our observations were not scheduled due to limited receiver changes. We are therefore re-proposing as formality. Since the proposal, we have obtained RFI measurements with the feed pointed at zenith. We are confident the dominant source of RFI can be found and removed. If observing at this band is possible, at least two scientific outputs relevant to global 21cm cosmology (among many others) are put within reach:

  13. 47 CFR 27.303 - Upper 700 MHz commercial and public safety coordination zone.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Upper 700 MHz commercial and public safety coordination zone. 27.303 Section 27.303 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and...

  14. 47 CFR 27.303 - Upper 700 MHz commercial and public safety coordination zone.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Upper 700 MHz commercial and public safety coordination zone. 27.303 Section 27.303 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and...

  15. 47 CFR 27.701 - 698-746 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false 698-746 MHz bands subject to competitive bidding. 27.701 Section 27.701 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Competitive Bidding Procedures for the...

  16. 47 CFR 27.701 - 698-746 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false 698-746 MHz bands subject to competitive bidding. 27.701 Section 27.701 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Competitive Bidding Procedures for the...

  17. 47 CFR 27.701 - 698-746 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false 698-746 MHz bands subject to competitive bidding. 27.701 Section 27.701 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Competitive Bidding Procedures for the...

  18. 47 CFR 27.701 - 698-746 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false 698-746 MHz bands subject to competitive bidding. 27.701 Section 27.701 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Competitive Bidding Procedures for the...

  19. 47 CFR 27.701 - 698-746 MHz bands subject to competitive bidding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false 698-746 MHz bands subject to competitive bidding. 27.701 Section 27.701 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Competitive Bidding Procedures for the...

  20. Dielectric properties of sweetpotato purees at 915 MHz as affected by temperature and chemical composition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A process for rapid sterilization and aseptic packaging of sweetpotato puree using a continuous flow microwave system operating at 915 MHz has been successfully developed. This development offers an opportunity for converting sweetpotato roots into a functional ingredient for the food industry....

  1. 78 FR 1188 - Commercial Operations in the 3550-3650 MHz Band

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-08

    ... Citizens Broadband Radio Service under part 95 of its rules for shared small cell use in the 3550-3650 MHz... Satellite Service (FSS) users. The Commission also seeks comment on how the unique characteristics of small cells may help reduce the need for geographic protections and enable shared access of the 3.5 GHz...

  2. 1020MHz single-channel proton fast magic angle spinning solid-state NMR spectroscopy.

    PubMed

    Pandey, Manoj Kumar; Zhang, Rongchun; Hashi, Kenjiro; Ohki, Shinobu; Nishijima, Gen; Matsumoto, Shinji; Noguchi, Takashi; Deguchi, Kenzo; Goto, Atsushi; Shimizu, Tadashi; Maeda, Hideaki; Takahashi, Masato; Yanagisawa, Yoshinori; Yamazaki, Toshio; Iguchi, Seiya; Tanaka, Ryoji; Nemoto, Takahiro; Miyamoto, Tetsuo; Suematsu, Hiroto; Saito, Kazuyoshi; Miki, Takashi; Ramamoorthy, Ayyalusamy; Nishiyama, Yusuke

    2015-12-01

    This study reports a first successful demonstration of a single channel proton 3D and 2D high-throughput ultrafast magic angle spinning (MAS) solid-state NMR techniques in an ultra-high magnetic field (1020MHz) NMR spectrometer comprised of HTS/LTS magnet. High spectral resolution is well demonstrated.

  3. 78 FR 70499 - Private Land Mobile Radio Stations Below 800 MHz

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-26

    ... announcing the effective date of those rules. DATES: 47 CFR 90.187 and 47 CFR 90.425 published at 78 FR 28749... of part 90 of the Commission's rules, FCC 13-52, published at 78 FR 28749, May 16, 2013. The OMB...: October 31, 2016. ] Title: Section 90.187, Trunking in the Bands Between 150 and 512 MHz; and Sections...

  4. Dynamic Wetting at MHz Vibration: Simple and Complex Liquid Films on an Ultrasonic Actuator

    NASA Astrophysics Data System (ADS)

    Manor, Ofer; Althshuler, Gennady; Mhatre, Sameer; Abezgauz, Ludmila

    2015-11-01

    We excite simple and complex liquid films on ultrasonic actuators that produce a MHz substrate vibration in the form of a surface acoustic wave (SAW). Transfer of momentum from the MHz vibration in the solid substrate to the neighboring liquid translates to convective stresses within the liquid and on the film free boundary. These stresses further invoke various flow mechanisms, also known as acoustic streaming and may support dynamic wetting or dewetting of liquid films. In particular, we use theory and experiment to study the interplay between viscous, capillary, and the vibrational dynamics of liquid films and their internal structure. We employ MHz ultrasonic actuators to study the dynamic wetting and dewetting of free and confined films of oil and water/surfactant solutions on flat surfaces and within microfluidic channels. We further excite films of evaporating solutions and suspensions in order to study the active influence of the solid vibration on the geometry of the molecule and particle patterns that are deposited in this process. We show the physics underlying these different systems may be explained using the convective dynamics the MHz substrate vibration excites in liquid films.

  5. 47 CFR 90.266 - Long distance communications on frequencies below 25 MHz.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Long distance communications on frequencies below 25 MHz. 90.266 Section 90.266 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Standards for Special Frequencies or Frequency Bands § 90.266 Long...

  6. 47 CFR 25.265 - Acceptance of interference in 2000-2020 MHz.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Acceptance of interference in 2000-2020 MHz. 25.265 Section 25.265 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.265 Acceptance of interference in 2000-2020...

  7. 47 CFR 25.265 - Acceptance of interference in 2000-2020 MHz.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Acceptance of interference in 2000-2020 MHz. 25.265 Section 25.265 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.265 Acceptance of interference in 2000-2020...

  8. Imaging Buried Culverts Using Ground Penetrating Radar: Comparing 100 MHZ Through 1 GHZ Antennae

    NASA Astrophysics Data System (ADS)

    Abdul Aziz, A.; Stewart, R. R.; Green, S. L.

    2013-12-01

    *Aziz, A A aabdulaziz@uh.edu Allied Geophysical Lab, Department of Earth and Atmospheric Sciences, University of Houston, TX, USA Stewart, R R rrstewart@uh.edu Allied Geophysical Lab, Department of Earth and Atmospheric Sciences, University of Houston, TX, USA *Green, S L slgreen@yahoo.com Allied Geophysical Lab, Department of Earth and Atmospheric Sciences, University of Houston, TX, USA A 3D ground penetrating radar (GPR) survey, using three different frequency antennae, was undertaken to image buried steel culverts at the University of Houston's La Marque Geophysical Observatory 30 miles south of Houston, Texas. The four culverts, under study, support a road crossing one of the area's bayous. A 32 m by 4.5 m survey grid was designed on the road above the culverts and data were collected with 100 MHz, 250 MHz, and 1 GHz antennae. We used an orthogonal acquisition geometry for the three surveys. Inline sampling was from 1.0 cm to 10 cm (from 1 GHz to 100 MHz antenna) with inline and crossline spacings ranging from 0.2 m to 0.5 m. We used an initial velocity of 0.1 m/ns (from previous CMP work at the site) for the display purposes. The main objective of the study was to analyze the effect of different frequency antennae on the resultant GPR images. We are also interested in the accuracy and resolution of the various images, in addition to developing an optimal processing flow.The data were initially processed with standard steps that included gain enhancement, dewow and temporal-filtering, background suppression, and 2D migration. Various radar velocities were used in the 2D migration and ultimately 0.12 m/ns was used. The data are complicated by multipathing from the surface and between culverts (from modeling). Some of this is ameliorated via deconvolution. The top of each of the four culverts was evident in the GPR images acquired with the 250 MHz and 100 MHz antennas. For 1 GHz, the top of the culvert was not clear due to the signal's attenuation. The 250 MHz

  9. The effect of radio frequency interference on the 136- to 138-MHz return link and 400.5- to 401.5-MHz forward link of the Tracking and Data Relay Satellite System

    NASA Technical Reports Server (NTRS)

    Jenny, J.; Lyttle, J. D.

    1973-01-01

    The purpose is to update the RFI estimates in the 136- to 138-MHz VHF band and to make estimates for the first time for the 400.5- to 401.5-MHz UHF band. These preliminary predictions are based on primarily ITU frequency-registration data, with missing data bridged by engineering judgement.

  10. Preferred Frequency Range, Technical Characteristics, and Interference Assessment for a Microwave Observatory of Subsurface and Subcanopy (MOSS) for 1 MHZ Bandwidth in the Frequency Range of 100-150 MHz

    NASA Technical Reports Server (NTRS)

    Honeycutt, Bryan L.

    2005-01-01

    This document presents rationale for the frequency band selection, technical and operational characteristics of active spaceborne sensors in the Earth Exploration-Satellite Service (active), and interference assessment for a 1 MHz bandwidth sensor in the 100-150 MHz frequency range. The active spaceborne sensors expected to be operating in the frequency range of 100-150 MHz is the synthetic aperture radar (SAR) such as the MOSS. The technical characteristics, mission objectives, orbital parameters, design parameters, antenna characteristics, and preliminary interference assessment are given for MOSS. The purpose of the document is to provide rationale for the frequency band selection, technical characteristics of the active spaceborne sensor Microwave Observatory of Subsurface and Subcanopy (MOSS) that can be used to analyze the compatibility of active spaceborne sensors and other systems of 1 MHz bandwidth in the 100-150 MHz frequency band.

  11. Why do the Solar Type III Burst emit the maximum of their radio energy around 1 MHz ?

    NASA Astrophysics Data System (ADS)

    Maksimovic, Milan; Krupar, Vratislav; Kontar, Eduard; Zaslavsky, Arnaud; Pascal, Louis; Reid, Hamish; Lecacheux, Alain; Bonnin, Xavier; Santolik, Ondrej; Vilmer, Nicole

    2014-05-01

    We present a statistical survey of a few hundred of Type III bursts observed from about 100 KHz up to about 400 MHz. When displayed as a function of the frequency, the radio flux exhibits a clear maximum at about 1 MHz. This property, already reported in previous studies, will be described in more details and possible explanations about its origin will be discussed.

  12. 47 CFR 90.717 - Channels available for nationwide systems in the 220-222 MHz band.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Licensing and Use of Frequencies in the 220-222 MHz Band § 90.717 Channels available for nationwide systems in the 220-222 MHz band. (a) Channels 51-60, 81-90, and 141-150 are 10-channel blocks available to..., and 156-160 are 5-channel blocks available to non-Government applicants only for...

  13. 47 CFR 90.717 - Channels available for nationwide systems in the 220-222 MHz band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Licensing and Use of Frequencies in the 220-222 MHz Band § 90.717 Channels available for nationwide systems in the 220-222 MHz band. (a) Channels 51-60, 81-90, and 141-150 are 10-channel blocks available to..., and 156-160 are 5-channel blocks available to non-Government applicants only for...

  14. 47 CFR 25.252 - Special requirements for ancillary terrestrial components operating in the 2000-2020 MHz/2180...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Special requirements for ancillary terrestrial components operating in the 2000-2020 MHz/2180-2200 MHz bands. 25.252 Section 25.252 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS...

  15. 47 CFR 25.252 - Special requirements for ancillary terrestrial components operating in the 2000-2020 MHz/2180...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Special requirements for ancillary terrestrial components operating in the 2000-2020 MHz/2180-2200 MHz bands. 25.252 Section 25.252 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS...

  16. 47 CFR 25.252 - Special requirements for ancillary terrestrial components operating in the 2000-2020 MHz/2180...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Special requirements for ancillary terrestrial components operating in the 2000-2020 MHz/2180-2200 MHz bands. 25.252 Section 25.252 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS...

  17. 47 CFR 27.1111 - Relocation of fixed microwave service licensees in the 2110-2150 MHz band.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Relocation of fixed microwave service licensees..., 2110-2155 MHz, 2160-2180 MHz Bands Relocation of Incumbents § 27.1111 Relocation of fixed microwave... contain provisions governing the relocation of incumbent fixed microwave service licensees in the...

  18. 47 CFR 27.1111 - Relocation of fixed microwave service licensees in the 2110-2150 MHz band.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Relocation of fixed microwave service licensees..., 2110-2155 MHz, 2160-2180 MHz Bands Relocation of Incumbents § 27.1111 Relocation of fixed microwave... contain provisions governing the relocation of incumbent fixed microwave service licensees in the...

  19. 47 CFR 27.1111 - Relocation of fixed microwave service licensees in the 2110-2150 MHz band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Relocation of fixed microwave service licensees..., 2110-2155 MHz, 2160-2180 MHz Bands Relocation of Incumbents § 27.1111 Relocation of fixed microwave... contain provisions governing the relocation of incumbent fixed microwave service licensees in the...

  20. 47 CFR 15.323 - Specific requirements for devices operating in the 1920-1930 MHz band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... intended transmission and have a maximum reaction time less than 50xSQRT (1.25/emission bandwidth in MHz... reaction time shall be 35xSQRT (1.25/emission bandwidth in MHz) microseconds but shall not be required to... given frequency carrier shall maintain a frame repetition rate with a frequency stability of at least...

  1. 47 CFR 22.853 - Eligibility to hold interest in licenses limited to 3 MHz of spectrum.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... limited to 3 MHz of spectrum. 22.853 Section 22.853 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Aviation Air-Ground Systems § 22.853 Eligibility to hold interest in licenses limited to 3 MHz of spectrum... authorizing the use of more than three megahertz of spectrum (either shared or exclusive) in the 800...

  2. 47 CFR 90.1432 - Conditions for waiver to allow limited and temporary wideband operations in the 700 MHz public...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of the 700 MHz band public safety spectrum except where the Commission has granted a waiver pursuant... spectrum. Where spectrum in the narrowband segment or internal guard band segment is unavailable for... temporary wideband operations in the 700 MHz public safety spectrum. 90.1432 Section...

  3. 47 CFR 22.853 - Eligibility to hold interest in licenses limited to 3 MHz of spectrum.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... limited to 3 MHz of spectrum. 22.853 Section 22.853 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Aviation Air-Ground Systems § 22.853 Eligibility to hold interest in licenses limited to 3 MHz of spectrum... authorizing the use of more than three megahertz of spectrum (either shared or exclusive) in the 800...

  4. 76 FR 71909 - Service Rules for the 698-806 MHz Band, Revision of the Commission's Rules Regarding Public...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-21

    ...; FCC 07-132] Service Rules for the 698-806 MHz Band, Revision of the Commission's Rules Regarding Public Safety Spectrum Requirements, and a Declaratory Ruling on Reporting Requirement Under the... the Service Rules for the 698-806 MHz Band proceeding, to the extent they contained...

  5. 47 CFR 22.853 - Eligibility to hold interest in licenses limited to 3 MHz of spectrum.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... limited to 3 MHz of spectrum. 22.853 Section 22.853 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Aviation Air-Ground Systems § 22.853 Eligibility to hold interest in licenses limited to 3 MHz of spectrum... authorizing the use of more than three megahertz of spectrum (either shared or exclusive) in the 800...

  6. 47 CFR 22.853 - Eligibility to hold interest in licenses limited to 3 MHz of spectrum.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... limited to 3 MHz of spectrum. 22.853 Section 22.853 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Aviation Air-Ground Systems § 22.853 Eligibility to hold interest in licenses limited to 3 MHz of spectrum... authorizing the use of more than three megahertz of spectrum (either shared or exclusive) in the 800...

  7. 47 CFR 15.323 - Specific requirements for devices operating in the 1920-1930 MHz band.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... for the purpose of denying fair access to spectrum to other devices. (d) Emissions outside the band... the 1920-1930 MHz band. 15.323 Section 15.323 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... requirements for devices operating in the 1920-1930 MHz band. (a) Operation shall be contained within the...

  8. 47 CFR 90.1432 - Conditions for waiver to allow limited and temporary wideband operations in the 700 MHz public...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of the 700 MHz band public safety spectrum except where the Commission has granted a waiver pursuant... spectrum. Where spectrum in the narrowband segment or internal guard band segment is unavailable for... temporary wideband operations in the 700 MHz public safety spectrum. 90.1432 Section...

  9. 75 FR 6316 - Revisions to Rules Authorizing the Operation of Low Power Auxiliary Stations in the 698-806 MHz...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-09

    ... 698-806 MHz Band; Public Interest Spectrum Coalition, Petition for Rulemaking Regarding Low Power... Stations in the 698-806 MHz Band; Public Interest Spectrum Coalition, Petition for Rulemaking Regarding Low..., 2010 (75 FR 3622). DATES: February 9, 2010. FOR FURTHER INFORMATION CONTACT: Paul D'Ari,...

  10. 47 CFR 15.323 - Specific requirements for devices operating in the 1920-1930 MHz band.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... for the purpose of denying fair access to spectrum to other devices. (d) Emissions outside the band... the 1920-1930 MHz band. 15.323 Section 15.323 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... requirements for devices operating in the 1920-1930 MHz band. (a) Operation shall be contained within the...

  11. 47 CFR 22.853 - Eligibility to hold interest in licenses limited to 3 MHz of spectrum.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... limited to 3 MHz of spectrum. 22.853 Section 22.853 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Aviation Air-Ground Systems § 22.853 Eligibility to hold interest in licenses limited to 3 MHz of spectrum... authorizing the use of more than three megahertz of spectrum (either shared or exclusive) in the 800...

  12. 47 CFR 27.1132 - Protection of incumbent operations in the 2150-2160/62 MHz band.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Protection of incumbent operations in the 2150-2160/62 MHz band. 27.1132 Section 27.1132 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz,...

  13. 47 CFR 27.1132 - Protection of incumbent operations in the 2150-2160/62 MHz band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Protection of incumbent operations in the 2150-2160/62 MHz band. 27.1132 Section 27.1132 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz,...

  14. 47 CFR 27.1132 - Protection of incumbent operations in the 2150-2160/62 MHz band.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Protection of incumbent operations in the 2150-2160/62 MHz band. 27.1132 Section 27.1132 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1710-1755 MHz,...

  15. 47 CFR 90.719 - Individual channels available for assignment in the 220-222 MHz band.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Individual channels available for assignment in... Licensing and Use of Frequencies in the 220-222 MHz Band § 90.719 Individual channels available for assignment in the 220-222 MHz band. (a) Channels 171 through 200 are available to both Government and...

  16. 77 FR 41473 - Proposed Technical Standard Order (TSO)-C126b, 406 MHz Emergency Locator Transmitters (ELT) and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-13

    ... Federal Aviation Administration Proposed Technical Standard Order (TSO)-C126b, 406 MHz Emergency Locator Transmitters (ELT) and Notice of Intent To Withdraw TSO Authorizations (TSOA) for TSO-C91a, Emergency Locator Transmitter (ELT) Equipment, and TSO-C126/C126a, 406 MHz Emergency Locator Transmitters (ELT) AGENCY:...

  17. 78 FR 77029 - Wireless Telecommunications Bureau Seeks Comment on a Proposal To License the 600 MHz Band Using...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-20

    ... 77 FR 69934 November 21, 2012 (NPRM), the Commission sought public comment on creating a 600 MHz band... MHz Bands 78 FR 51559 August 20, 2013 (AWS-3 NPRM), WTB seeks comment on applying this approach. 4. As... Electronic Comment Filing System (ECFS). See Electronic Filing of Documents in Rulemaking Proceedings, 63...

  18. 47 CFR 22.877 - Unacceptable interference to part 90 non-cellular 800 MHz licensees from commercial aviation air...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-cellular 800 MHz licensees from commercial aviation air-ground systems. 22.877 Section 22.877...-Ground Radiotelephone Service Commercial Aviation Air-Ground Systems § 22.877 Unacceptable interference to part 90 non-cellular 800 MHz licensees from commercial aviation air-ground systems. The...

  19. 47 CFR 22.877 - Unacceptable interference to Part 90 non-cellular 800 MHz licensees from commercial aviation air...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-cellular 800 MHz licensees from commercial aviation air-ground systems. 22.877 Section 22.877...-Ground Radiotelephone Service Commercial Aviation Air-Ground Systems § 22.877 Unacceptable interference to Part 90 non-cellular 800 MHz licensees from commercial aviation air-ground systems. The...

  20. 47 CFR 22.877 - Unacceptable interference to Part 90 non-cellular 800 MHz licensees from commercial aviation air...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-cellular 800 MHz licensees from commercial aviation air-ground systems. 22.877 Section 22.877...-Ground Radiotelephone Service Commercial Aviation Air-Ground Systems § 22.877 Unacceptable interference to Part 90 non-cellular 800 MHz licensees from commercial aviation air-ground systems. The...

  1. 47 CFR 22.877 - Unacceptable interference to Part 90 non-cellular 800 MHz licensees from commercial aviation air...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-cellular 800 MHz licensees from commercial aviation air-ground systems. 22.877 Section 22.877...-Ground Radiotelephone Service Commercial Aviation Air-Ground Systems § 22.877 Unacceptable interference to Part 90 non-cellular 800 MHz licensees from commercial aviation air-ground systems. The...

  2. 47 CFR 22.877 - Unacceptable interference to Part 90 non-cellular 800 MHz licensees from commercial aviation air...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-cellular 800 MHz licensees from commercial aviation air-ground systems. 22.877 Section 22.877...-Ground Radiotelephone Service Commercial Aviation Air-Ground Systems § 22.877 Unacceptable interference to Part 90 non-cellular 800 MHz licensees from commercial aviation air-ground systems. The...

  3. A 300 MHz and 600 MHz proton NMR study of a 12 base pair restriction fragment: investigation of structure by relaxation measurements.

    PubMed Central

    Early, T A; Kearns, D R; Hillen, W; Wells, R D

    1980-01-01

    The 1H NMR spectrum of a 12 base pair DNA restriction fragment has been measured at 300 and 600 MHz and resonances from over 70 protons are individually resolved. Relaxation rate measurements have been carried out at 300 MHz and compared with the theoretical predictions obtained using an isotropic rigid rotor model with coordinates derived from a Dreiding model of DNA. The model gives results that are in excellent agreement with experiment for most protons when a 7 nsec rotational correlation time is used, although agreement is improved for certain base protons by using a shorter correlation time for the sugar group, or by increasing the sugar-base interproton distances. A comparison of non-selective and selective spin-lattice relaxation rates for carbon bound protons indicates that there is extensive spin diffusion even in this short DNA fragment. Examination of the spin-spin relaxation rates for the same type of proton on different base pairs reveals little sequence effect on conformation. PMID:6258152

  4. Optimization of dynamic nuclear polarization experiments in aqueous solution at 15 MHz/9.7 GHz: a comparative study with DNP at 140 MHz/94 GHz.

    PubMed

    Türke, Maria-Teresa; Tkach, Igor; Reese, Marcel; Höfer, Peter; Bennati, Marina

    2010-06-14

    Dynamic nuclear polarization is emerging as a potential tool to increase the sensitivity of NMR aiming at the detection of macromolecules in liquid solution. One possibility for such an experimental design is to perform the polarization step between electrons and nuclei at low magnetic fields and then transfer the sample to a higher field for NMR detection. In this case, an independent optimization of the polarizer and detection set ups is required. In the present paper we describe the optimization of a polarizer set up at 15 MHz (1)H NMR/9.7 GHz EPR frequencies based on commercial hardware. The sample consists of the nitroxide radical TEMPONE-D,(15)N in water, for which the dimensions were systematically decreased to fit the homogeneous B(1) region of a dielectric ENDOR resonator. With an available B(1) microwave field up to 13 G we observe a maximum DNP enhancement of -170 at room temperature by irradiating on either one of the EPR lines. The DNP enhancement was saturated at all polarizer concentrations. Pulsed ELDOR experiments revealed that the saturation level of the two hyperfine lines is such that the DNP enhancements are well consistent with the coupling factors derived from NMRD data. By raising the polarizing field and frequencies 10-fold, i.e. to 140 MHz (1)H/94 GHz EPR, we reach an enhancement of -43 at microwave field strengths (B(1) approximately 5 G). The results are discussed in view of an application for a DNP spectrometer.

  5. Improved Anatomical Specificity of Non-invasive Neuro-stimulation by High Frequency (5 MHz) Ultrasound

    NASA Astrophysics Data System (ADS)

    Li, Guo-Feng; Zhao, Hui-Xia; Zhou, Hui; Yan, Fei; Wang, Jing-Yao; Xu, Chang-Xi; Wang, Cong-Zhi; Niu, Li-Li; Meng, Long; Wu, Song; Zhang, Huai-Ling; Qiu, Wei-Bao; Zheng, Hai-Rong

    2016-04-01

    Low frequency ultrasound (<1 MHz) has been demonstrated to be a promising approach for non-invasive neuro-stimulation. However, the focal width is limited to be half centimeter scale. Minimizing the stimulation region with higher frequency ultrasound will provide a great opportunity to expand its application. This study first time examines the feasibility of using high frequency (5 MHz) ultrasound to achieve neuro-stimulation in brain, and verifies the anatomical specificity of neuro-stimulation in vivo. 1 MHz and 5 MHz ultrasound stimulation were evaluated in the same group of mice. Electromyography (EMG) collected from tail muscles together with the motion response videos were analyzed for evaluating the stimulation effects. Our results indicate that 5 MHz ultrasound can successfully achieve neuro-stimulation. The equivalent diameter (ED) of the stimulation region with 5 MHz ultrasound (0.29 ± 0.08 mm) is significantly smaller than that with 1 MHz (0.83 ± 0.11 mm). The response latency of 5 MHz ultrasound (45 ± 31 ms) is also shorter than that of 1 MHz ultrasound (208 ± 111 ms). Consequently, high frequency (5 MHz) ultrasound can successfully activate the brain circuits in mice. It provides a smaller stimulation region, which offers improved anatomical specificity for neuro-stimulation in a non-invasive manner.

  6. Improved Anatomical Specificity of Non-invasive Neuro-stimulation by High Frequency (5 MHz) Ultrasound

    PubMed Central

    Li, Guo-Feng; Zhao, Hui-Xia; Zhou, Hui; Yan, Fei; Wang, Jing-Yao; Xu, Chang-Xi; Wang, Cong-Zhi; Niu, Li-Li; Meng, Long; Wu, Song; Zhang, Huai-Ling; Qiu, Wei-Bao; Zheng, Hai-Rong

    2016-01-01

    Low frequency ultrasound (<1 MHz) has been demonstrated to be a promising approach for non-invasive neuro-stimulation. However, the focal width is limited to be half centimeter scale. Minimizing the stimulation region with higher frequency ultrasound will provide a great opportunity to expand its application. This study first time examines the feasibility of using high frequency (5 MHz) ultrasound to achieve neuro-stimulation in brain, and verifies the anatomical specificity of neuro-stimulation in vivo. 1 MHz and 5 MHz ultrasound stimulation were evaluated in the same group of mice. Electromyography (EMG) collected from tail muscles together with the motion response videos were analyzed for evaluating the stimulation effects. Our results indicate that 5 MHz ultrasound can successfully achieve neuro-stimulation. The equivalent diameter (ED) of the stimulation region with 5 MHz ultrasound (0.29 ± 0.08 mm) is significantly smaller than that with 1 MHz (0.83 ± 0.11 mm). The response latency of 5 MHz ultrasound (45 ± 31 ms) is also shorter than that of 1 MHz ultrasound (208 ± 111 ms). Consequently, high frequency (5 MHz) ultrasound can successfully activate the brain circuits in mice. It provides a smaller stimulation region, which offers improved anatomical specificity for neuro-stimulation in a non-invasive manner. PMID:27093909

  7. Development of a 402.5 MHz 140 kW Inductive Output Tube

    SciTech Connect

    R. Lawrence Ives; Michael Read, Robert Jackson

    2012-05-09

    This report contains the results of Phase I of an SBIR to develop a Pulsed Inductive Output Tube (IOT) with 140 kW at 400 MHz for powering H-proton beams. A number of sources, including single beam and multiple beam klystrons, can provide this power, but the IOT provides higher efficiency. Efficiencies exceeding 70% are routinely achieved. The gain is typically limited to approximately 24 dB; however, the availability of highly efficient, solid state drivers reduces the significance of this limitation, particularly at lower frequencies. This program initially focused on developing a 402 MHz IOT; however, the DOE requirement for this device was terminated during the program. The SBIR effort was refocused on improving the IOT design codes to more accurately simulate the time dependent behavior of the input cavity, electron gun, output cavity, and collector. Significant improvement was achieved in modeling capability and simulation accuracy.

  8. Electromagnetic Interference Analysis Based on Total Harmonic Distortion Measurement in 900MHz Cordless Telephones

    NASA Astrophysics Data System (ADS)

    Park, Jeung Geun; Kim, Che Young

    In this paper a new electromagnetic (EM) interference analysis is proposed using the total harmonic distortion (THD) measurement of the audio signal by the 900MHz cordless telephones. The cordless telephone network in 900MHz was built up to be weak in EM interference. 400 and 800Hz of the sine-wave signal were used in transmitter (TX) system, and the receiver (RX) system was exposed to the EM interference. The THD value varies as the level of the exposed EM interference changes. The model of the cordless telephone also affects the THD value. By using fluctuation of the THD value depending on the amount of the exposure, the threshold value of the interference electric field strength was derived. Based on the derived threshold value of the electric field strength, validity of the regulation value for low power radio devices by CISPR 22 [CLASS B] and FCC is discussed.

  9. Overview of the development of high-resolution 920 MHz NMR in NIMS

    NASA Astrophysics Data System (ADS)

    Shimizu, Tadashi; Hashi, Kenjiro; Goto, Atsushi; Tansyo, Masataka; Kiyoshi, Tsukasa; Matsumoto, Shinji; Wada, Hitoshi; Fujito, Teruaki; Hasegawa, Ken-ichi; Kirihara, Noriaki; Suematsu, Hiroto; Kida, Yoshiki; Yoshikawa, Masatoshi; Miki, Takashi; Ito, Satoshi; Hamada, Mamoru; Hayashi, Seiji

    2004-04-01

    We have developed a 920 MHz NMR system and performed the proton NMR measurement of ethylbenzene and water using the superconducting magnet operating at 21.6 T ( 920 MHz for proton), which is the highest field produced by a superconducting NMR magnet in the persistent mode. From the NMR measurements, it is verified that both homogeneity and stability of the magnet have a specification sufficient for a high-resolution NMR. The sensitivity has been examined by 1H NMR of 0.1% ethylbenzene in Wilmad 555 tube and obtained the signal-to-noise ratio as S/ N=2981, which is the highest record, to our knowledge, among the room temperature measurements.

  10. Distribution of mean Doppler shift, spectral width, and skewness of coherent 50-MHz auroral radar backscatter

    SciTech Connect

    Watermann, J.; McNamara, A.G. ); Sofko, G.J.; Koehler, J.A. )

    1989-06-01

    Some 7,700 radio aurora spectra obtained from a six link 50-MHz CW radar network set up on the Canadian prairies were analyzed with respect to the distributions of mean Doppler shift, spectral width and skewness. A comparison with recently published SABRE results obtained at 153 MHz shows substantial differences in the distributions which are probably due to different experimental and geophysical conditions. The spectra are mostly broad with mean Doppler shifts close to zero (type II spectra). The typical groupings of type I and type III spectra are clearly identified. All types appear to be in general much more symmetric than those recorded with SABRE, and the skewness is only weakly dependent on the sign of the mean Doppler shift. Its distribution peaks near zero and shows a weak positive correlation with the type II Doppler shifts while the mostly positive type I Doppler shifts are slightly negatively correlated with the skewness.

  11. Electromagnetic waves of 900 MHz in acute pentylenetetrazole model in ontogenesis in mice.

    PubMed

    Erdinc, O O; Baykul, M C; Ozdemir, O; Ozkan, S; Sirmagul, B; Oner, S D; Ozdemir, G

    2003-10-01

    The purpose of this study was to measure the effects of electromagnetic waves (EMW) at 900 MHz. EMW were produced by a signal generator and were administered to mice via an antenna. The frequency of the waves was tested by a spectrum analyser and a frequency-meter. The emitted power was 0.25 mW. A total of 117 mice (59 prepubertal and 58 adult) was used. Mice were exposed to EMW or sham radiation for 2 h and 20 h before an injection of pentylenetetrazole (PTZ). A statistically significant difference was found between the latency measurements within 20 h for prepubertal mice in stages 1 and 2 ( p<0.05). The effects on prepubertal mice of long-term 900 MHz EMW in a PTZ model may be an indication of possible problems in developing brains. PMID:14600821

  12. Dicke’S Superradiance in Astrophysics. II. The OH 1612 MHz Line

    NASA Astrophysics Data System (ADS)

    Rajabi, Fereshteh; Houde, Martin

    2016-09-01

    We apply the concept of superradiance that was introduced by Dicke in 1954 to the OH molecule 1612 MHz spectral line, which is often used for the detection of masers in the circumstellar envelopes of evolved stars. Because the detection of 1612 MHz OH masers in the outer shells of envelopes of these stars implies the existence of a population inversion and a high level of velocity coherence, and that these are two necessary requirements for superradiance, we investigate whether superradiance can also happen in these regions. Superradiance is characterized by high-intensity, spatially compact, burst-like features taking place over timescales on the order of seconds to years, depending on the size and physical conditions present in the regions harboring such sources of radiation. Our analysis suggests that superradiance provides a valid explanation for previous observations of intensity flares detected in that spectral line for the U Orionis Mira star and the IRAS 18276-1431 preplanetary nebula.

  13. 4D Optical Coherence Tomography based Microangiography achieved by 1.6 MHz FDML Swept source

    PubMed Central

    Zhi, Zhongwei; Qin, Wan; Wang, Jingang; Wei, Wei; Wang, Ruikang K.

    2015-01-01

    We demonstrate the use of an ultra-high speed swept-source optical coherence tomography (OCT) to achieve optical microangiography (OMAG) of microcirculatory tissue beds in vivo. The system is based on a 1310 nm Fourier domain mode locking (FDML) laser with 1.6MHz A-line rate, providing a frame rate of 3.415 KHz, an axial resolution of ~10 µm and signal to noise ratio of 102 dB. Motion from blood flow causes change in OCT signals between consecutive B-frames acquired at the same location. Intensity based inter-frame subtraction algorithm is applied to extract blood flow from tissue background without any motion correction. We demonstrate the capability of this 1.6 MHz OCT system for 4D optical microangiography of in vivo tissue at a volume rate of 4.7 volumes/s (volume size: 512×200×720 voxels). PMID:25872072

  14. The MWA GLEAM 4 Jy sample; a new large, bright radio source sample at 151 MHz

    NASA Astrophysics Data System (ADS)

    Jackson, C. A.; Franzen, T. M. O.; Seymour, N.; White, S. V.; Murphy, T.; Salder, E. M.; Callingham, J. R.; Hunstead, R. W.; Hughes, J.; Wall, J. V.; Bell, M. E.; Dwarakanath, K. S.; For, B.-Q.; Gaensler, B. M.; Hancock, P. J.; Hindson, L.; Hurley-Walker, N.; Johnston-Hollitt, M.; Kapinska, A. D.; Lenc, E.; McKinley, B.; Morgan, J.; Offringa, A. R.; Procopio, P.; Staveley-Smith, L.; Wayth, R. B.; Wu, C.; Zheng, Q.

    2015-10-01

    This paper outlines how the new GaLactic and Extragalactic All-sky MWA Survey (GLEAM, Wayth et al. 2015), observed by the Murchison Widefield Array covering the frequency range 72 - 231 MHz, allows identification of a new large, complete, sample of more than 2000 bright extragalactic radio sources selected at 151 MHz. With a flux density limit of 4 Jy this sample is significantly larger than the canonical fully-complete sample, 3CRR (Laing, Riley & Longair 1983). In analysing this small bright subset of the GLEAM survey we are also providing a first- user check of the GLEAM catalogue ahead of its public release (Hurley-Walker et al. in prep). Whilst significant work remains to fully characterise our new bright source sample, in time it will provide important constraints to evolutionary behaviour, across a wide redshift and intrinsic radio power range, as well as being highly complementary to results from targeted, small area surveys.

  15. Perpendicularly Biased YIG Tuners for the Fermilab Recycler 52.809 MHz Cavities

    SciTech Connect

    Madrak, R.; Kashikhin, V.; Makarov, A.; Wildman, D.

    2013-09-13

    For NOvA and future experiments requiring high intensity proton beams, Fermilab is in the process of upgrading the existing accelerator complex for increased proton production. One such improvement is to reduce the Main Injector cycle time, by performing slip stacking, previously done in the Main Injector, in the now repurposed Recycler Ring. Recycler slip stacking requires new tuneable RF cavities, discussed separately in these proceedings. These are quarter wave cavities resonant at 52.809 MHz with a 10 kHz tuning range. The 10 kHz range is achieved by use of a tuner which has an electrical length of approximately one half wavelength at 52.809 MHz. The tuner is constructed from 31/8” diameter rigid coaxial line, with 5 inches of its length containing perpendicularly biased, Al doped Yttrium Iron Garnet (YIG). The tuner design, measurements, and high power test results are presented.

  16. Self-stressing structures for wafer-level oxide breakdown to 200 MHz

    SciTech Connect

    Snyder, E.S.; Tanner, D.M.; Bowles, M.R.; Swanson, S.E.; Anderson, C.H.; Perry, J.P.

    1995-02-01

    We have demonstrated for the first time high frequency (210 MHz) oxide breakdown at the wafer-level using on-chip, self-stressing test structures. This is the highest frequency oxide breakdown that has been reported. We used these structures to characterize the variation in oxide breakdown with frequency (from 1 Hz to over 200 MHz) and duty cycle (from 10% to 90%). Since the stress frequency, duty cycle and temperature are controlled by DC signals in these structures, we used conventional DC wafer-level equipment without any special modifications (such as high frequency cabling). This self-stressing structure significantly reduces the cost of performing realistic high frequency oxide breakdown experiments necessary for developing reliability models and building-in-reliability.

  17. Radio propagation at 900 MHz in urban areas: Models with a fixed frequency and experimental results

    NASA Astrophysics Data System (ADS)

    Olivier, P.; Tiffon, J.

    1984-09-01

    Models which describe multipath propagation are examined in order to design a 900 MHz mobile communication system adapted to urban areas. A justification of the experimental data treatment is derived from this analysis. The measurements were made at a fixed 855 MHz frequency, transmitting from three locations. The fast fluctuations of the received signals are well represented by a Rayleigh process, which means that there are practically no paths of direct transmission. The coherence length is 1 m. The statistical distribution of the average field is Gaussian and the normal deviation decreases with the distance emitter-receiver. The empiric Okumura-Hata prediction model agrees well with the experimental results, giving an average cell field decreasing with distance with a logarithmic law.

  18. High-Frequency (>50 MHz) Medical Ultrasound Linear Arrays Fabricated From Micromachined Bulk PZT Materials

    PubMed Central

    Liu, Changgeng; Zhou, Qifa; Djuth, Frank T.; Shung, K. Kirk

    2012-01-01

    This paper describes the development and characterization of a high-frequency (65-MHz) ultrasound transducer linear array. The array was built from bulk PZT which was etched using an optimized chlorine-based plasma dry-etching process. The median etch rate of 8 μm/h yielded a good profile (wall) angle (>83°) and a reasonable processing time for etch depths up to 40 μm (which corresponds to a 50-MHz transducer). A backing layer with an acoustic impedance of 6 MRayl and a front-end polymer matching layer yielded a transducer bandwidth of 40%. The major parameters of the transducer have been characterized. The two-way insertion loss and crosstalk between adjacent channels at the center frequency are 26.5 and −25 dB, respectively. PMID:24626041

  19. Radio wave emitted by an extensive air showers in 10KHz to 1MHz region

    NASA Technical Reports Server (NTRS)

    Nichimura, J.

    1985-01-01

    The importance of radio waves in a frequency range of less than 1MHz in an EAS shower is discussed. Estimates of radio intensities at 10KHz, 100KHz and 1MHz in EAS showers made on the basis of the Kahn-Lerche theory. Negative charge excess in a shower is the main source of low frequency radio emission, in spite of the importance of the contribution of transverse current in the geomagnetic field in a higher frequency range. An estimate is also made for radio intensity produced when the shower hits the ground. The contribution of this process seems to be important at a large distance, i.e., beyond 1km from the shower axis.

  20. Beyond 40 MHz frontier: the future technologies for calibration and sensing of acoustic fields

    NASA Astrophysics Data System (ADS)

    Lewin, P. A.; Umchid, S.; Sutin, A.; Sarvazyan, A.

    2004-01-01

    Several techniques that are suitable for calibration of ultrasound hydrophones in the frequency range beyond 20 MHz are briefly reviewed. Attention is largely focused on substitution techniques because in contrast to the primary methods they are not as laborious and can be carried out relatively quickly. The techniques discussed include two acoustic procedures using swept frequency systems, an approach based on nonlinear propagation of acoustic waves in water medium, an acousto-optic technique that employs fiber optic sensors and a novel technique that is based on Time Reversed Acoustic (TRA) approach. It is shown that these techniques are capable of extending the frequency range in which the hydrophones can be calibrated up to 100 MHz. The importance of spatial averaging correction and its impact on the acoustic output measurements is also pointed out.

  1. Conceptual design of the 26. 7 MHz RF system for RHIC

    SciTech Connect

    Rose, J.; Deng, D.P.; McKenzie-Wilson, R.; Pirkl, W.; Ratti, A.

    1993-01-01

    The 26.7 MHz (harmonic No. h=342) RF system will be used to capture the injected bunched beam from the AGS and accelerate it to a kinetic energy of up to 250 GeV for protons; 100 GeV/u for gold ions. All ions except protons cross transition, and are finally transferred to a storage RF system working at 196 MHz. Each RHIC ring will be provided with two single-ended capacitively loaded quarter-wave cavities; each of these can be dynamically tuned by 100 kHz to compensate for the change in speed of the beam, and can deliver at least 200 kV voltage. A 100 kW tetrode amplifier with local RF feedback is directly coupled to the cavity to minimize phase delay. Prototypes of cavity and amplifier have been built and first test results are presented.

  2. Conceptual design of the 26.7 MHz RF system for RHIC

    SciTech Connect

    Rose, J.; Deng, D.P.; McKenzie-Wilson, R.; Pirkl, W.; Ratti, A.

    1993-06-01

    The 26.7 MHz (harmonic No. h=342) RF system will be used to capture the injected bunched beam from the AGS and accelerate it to a kinetic energy of up to 250 GeV for protons; 100 GeV/u for gold ions. All ions except protons cross transition, and are finally transferred to a storage RF system working at 196 MHz. Each RHIC ring will be provided with two single-ended capacitively loaded quarter-wave cavities; each of these can be dynamically tuned by 100 kHz to compensate for the change in speed of the beam, and can deliver at least 200 kV voltage. A 100 kW tetrode amplifier with local RF feedback is directly coupled to the cavity to minimize phase delay. Prototypes of cavity and amplifier have been built and first test results are presented.

  3. An electronically tuned, stable 8415-MHz dielectric resonator FET oscillator for space applications

    NASA Technical Reports Server (NTRS)

    Lakshminarayana, M.

    1988-01-01

    A voltage-controlled 8415 MHz FET oscillator stabilized by a dielectric resonator is described. The oscillator provides a linear electronic tuning range of over 3.2 MHz with a flat power output equal to +1.8 dBm (27 C nominal), a single-sideband noise to carrier ratio of -68 dBc/Hz at 1 kHz off carrier, and a frequency temperature coefficient of 0.54 part per million/C over a -24 to 75 C range. The oscillator withstood 150 krads(Si) of gamma radiation with no significant performance degradation. The overall performance of the oscillator is in many ways far superior to that of an equivalent bipolar oscillator for space applications.

  4. An electronically tuned, stable 8415 MHz dielectric resonator FET oscillator for space applications

    NASA Technical Reports Server (NTRS)

    Mysoor, Narayan R.

    1990-01-01

    A voltage-controlled 8415-MHz FET oscillator stabilized by a dielectric resonator is described. The oscillator provides over 3.2-MHz linear electronic tuning range with a flat power output equal to +1.8 dBm (27 C, nominal), a single-sideband noise-to-carrier ratio of -68 dBc/Hz at 1 kHz off carrier, and a frequency-temperature coefficient of 0.54 parts per million/C over a -24 C to 75 C range. The oscillator withstood 150 Krads (Si) of gamma radiation with no significant performance degradation. The overall performance of the FET oscillator is far superior in many ways to that of an equivalent bipolar oscillator for space applications. For space applications, the FET dielectric resonator oscillator (DRO) is preferred over bipolar DRO because of its lower DC power consumption, better thermal frequency stability, linear electronic tunability, and higher RF output power capability.

  5. Comparison of higher order modes damping techniques for 800 MHz single cell superconducting cavities

    NASA Astrophysics Data System (ADS)

    Shashkov, Ya. V.; Sobenin, N. P.; Petrushina, I. I.; Zobov, M. M.

    2014-12-01

    At present, applications of 800 MHz harmonic cavities in both bunch lengthening and shortening regimes are under consideration and discussion in the framework of the High Luminosity LHC project. In this paper we study electromagnetic characteristics of high order modes (HOMs) for a single cell 800 MHz superconducting cavity and arrays of such cavities connected by drifts tubes. Different techniques for the HOMs damping such as beam pipe grooves, coaxial-notch loads, fluted beam pipes etc. are investigated and compared. The influence of the sizes and geometry of the drift tubes on the HOMs damping is analyzed. The problems of a multipacting discharge in the considered structures are discussed and the operating frequency detuning due to the Lorentz force is evaluated.

  6. Measurement of electrodynamics characteristics of higher order modes for harmonic cavity at 2400 MHz

    NASA Astrophysics Data System (ADS)

    Shashkov, Ya V.; Sobenin, N. P.; Gusarova, M. A.; Lalayan, M. V.; Bazyl, D. S.; Donetskiy, R. V.; Orlov, A. I.; Zobov, M. M.; Zavadtsev, A. A.

    2016-09-01

    In the frameworks of the High Luminosity Large Hadron Collider (HL-LHC) upgrade program an application of additional superconducting harmonic cavities operating at 800 MHz is currently under discussion. As a possible candidate, an assembly of two cavities with grooved beam pipes connected by a drift tube and housed in a common cryomodule, was proposed. In this article we discuss measurements of loaded Q-factors of higher order modes (HOM) performed on a scaled aluminium single cell cavity prototype with the fundamental frequency of 2400 MHz and on an array of two such cavities connected by a narrow beam pipe. The measurements were performed for the system with and without the matching load in the drift tube..

  7. 916 MHz electromagnetic field exposure affects rat behavior and hippocampal neuronal discharge☆

    PubMed Central

    Hao, Dongmei; Yang, Lei; Chen, Su; Tian, Yonghao; Wu, Shuicai

    2012-01-01

    Wistar rats were exposed to a 916 MHz, 10 W/m2 mobile phone electromagnetic field for 6 hours a day, 5 days a week. Average completion times in an eight-arm radial maze were longer in the exposed rats than control rats after 4–5 weeks of exposure. Error rates in the exposed rats were greater than the control rats at 6 weeks. Hippocampal neurons from the exposed rats showed irregular firing patterns during the experiment, and they exhibited decreased spiking activity 6–9 weeks compared with that after 2–5 weeks of exposure. These results indicate that 916 MHz electromagnetic fields influence learning and memory in rats during exposure, but long-term effects are not obvious. PMID:25657684

  8. Statistical characterization of the dynamic human body communication channel at 45 MHz.

    PubMed

    Nie, Zedong; Ma, Jingjing; Chen, Hong; Wang, Lei

    2013-01-01

    The dynamic human body communication (HBC) propagation channel at 45 MHz was statistical characterized in this paper. A large amount of measurement data has been gathered in practical environment with real activities -treadmill running at different speeds in a lab room. The received power between two lower legs was acquired from three volunteers, with more than 60,000 snap shot of data in total. The statistical analyses confirmed that the HBC propagation channel at 45 MHz followed the Gamma and Lognormal distributions at the slower (2 km/h and 4 km/h) and faster (6 km/h and 8 km/h) running activities, respectively. The channel is insensitive to body motion with the maximum average fade duration is 0.0413 s and the most averaging bad channel duration time being less than 60 ms with the percentage of the bad channel duration time being less than 4.35%.

  9. Development of 400- to 450-MHz RFQ resonator-cavity mechanical designs

    SciTech Connect

    Hansborough, L.D.

    1982-01-01

    In the development of the radio-frequency quadrupole (RFQ) linac, the resonator cavity's mechanical design may be a challenge similar in magnitude to that of the development of the accelerator structure itself. Experience with the all-copper 425-MHz RFQ proof-of-principle linac has demonstrated that the resonator cavity must be structurally stiff and easily tunable. This experience has led to development of copper-plated steel structures having vanes that may be moved within a cylinder for tuning. Design of a flexible vane-to-cylinder radio-frequency (rf) joint, the vane, and the cylinder has many constraints dictated by the small-diameter cavities in the 400-MHz-frequency region. Two types of flexible, mechanical vane-to-cylinder rf joints are being developed at Los Alamos: the C-seal and the rf clamp-joint.

  10. Design of the 26.7 MHz rf cavity for RHIC

    SciTech Connect

    Rose, J.; Brodowski, J.; Deng, D.P.; Kwiatkowski, S.; Pirkl, W.; Ratti, A.

    1995-05-01

    The accelerating system for RHIC operates at 26.7 MHz (h = 342) and must capture the injected beam, accelerate it to top energy, and shorten the bunches prior to rebucketing into the storage (h = 2508) system. These different functions set the design parameters of the cavity. The frequency of 26.7 MHz has been chosen in order to provide large enough buckets to capture the injected beam from the AGS and a large linear region for debunching during a bunch rotation at top energy. Provision of the large linear region also dictates the voltage requirement of 400 kV per cavity. The cavity must be tuned {approximately}90 kHz to compensate for the change in speed of the gold beam.

  11. Simulation of the High-Pass Filter for 56MHz Cavity for RHIC

    SciTech Connect

    Wu, Q.; Ben-Zvi, I.

    2010-05-23

    The 56MHz Superconducting RF (SRF) cavity for RHIC places high demands High Order Mode (HOM) damping, as well as requiring a high field at gap with fundamental mode frequency. The damper of 56MHz cavity is designed to extract all modes to the resistance load outside, including the fundamental mode. Therefore, the circuit must incorporate a high-pass filter to reflect back the fundamental mode into the cavity. In this paper, we show the good frequency response map obtained from our filter's design. We extract a circuit diagram from the microwave elements that simulate well the frequency spectrum of the finalized filter. We also demonstrate that the power dissipation on the filter over its frequency range is small enough for cryogenic cooling.

  12. Sequential CW-EPR image acquisition with 760-MHz surface coil array.

    PubMed

    Enomoto, Ayano; Hirata, Hiroshi

    2011-04-01

    This paper describes the development of a surface coil array that consists of two inductively coupled surface-coil resonators, for use in continuous-wave electron paramagnetic resonance (CW-EPR) imaging at 760 MHz. To make sequential EPR image acquisition possible, we decoupled the surface coils using PIN-diode switches, to enable the shifting of the resonators resonance frequency by more than 200 MHz. To assess the effectiveness of the surface coil array in CW-EPR imaging, two-dimensional images of a solution of nitroxyl radicals were measured with the developed coil array. Compared to equivalent single coil acquired images, we found the visualized area to be extended approximately 2-fold when using the surface coil array. The ability to visualize larger regions of interest through the use of a surface coil array, may offer great potential in future EPR imaging studies. PMID:21320789

  13. Effects of microwaves (900 MHz) on peroxidase systems: A comparison between lactoperoxidase and horseradish peroxidase.

    PubMed

    Barteri, Mario; De Carolis, Roberta; Marinelli, Fiorenzo; Tomassetti, Goliardo; Montemiglio, Linda Celeste

    2016-01-01

    This work shows the effects of exposure to an electromagnetic field at 900 MHz on the catalytic activity of the enzymes lactoperoxidase (LPO) and horseradish peroxidase (HRP). Experimental evidence that irradiation causes conformational changes of the active sites and influences the formation and stability of the intermediate free radicals is documented by measurements of enzyme kinetics, circular dichroism spectroscopy (CD) and cyclic voltammetry. PMID:25577980

  14. Effects of microwaves (900 MHz) on peroxidase systems: A comparison between lactoperoxidase and horseradish peroxidase.

    PubMed

    Barteri, Mario; De Carolis, Roberta; Marinelli, Fiorenzo; Tomassetti, Goliardo; Montemiglio, Linda Celeste

    2016-01-01

    This work shows the effects of exposure to an electromagnetic field at 900 MHz on the catalytic activity of the enzymes lactoperoxidase (LPO) and horseradish peroxidase (HRP). Experimental evidence that irradiation causes conformational changes of the active sites and influences the formation and stability of the intermediate free radicals is documented by measurements of enzyme kinetics, circular dichroism spectroscopy (CD) and cyclic voltammetry.

  15. 47 CFR 95.1223 - Registration and frequency coordination in the 2360-2390 MHz Band.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 and approved by the Director of... MBAN is within the line of sight of an AMT receive facility in the 2360-2390 MHz band and notify the...) of this section. (1) If the MBAN is beyond the line of sight of an AMT receive facility, it...

  16. 47 CFR 95.1223 - Registration and frequency coordination in the 2360-2390 MHz Band.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 and approved by the Director of... MBAN is within the line of sight of an AMT receive facility in the 2360-2390 MHz band and notify the...) of this section. (1) If the MBAN is beyond the line of sight of an AMT receive facility, it...

  17. 47 CFR 95.1223 - Registration and frequency coordination in the 2360-2390 MHz Band.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 and approved by the Director of... MBAN is within the line of sight of an AMT receive facility in the 2360-2390 MHz band and notify the...) of this section. (1) If the MBAN is beyond the line of sight of an AMT receive facility, it...

  18. A 70-MHz 32-b microprocessor with 1. 0-. mu. m BiCMOS macrocell library

    SciTech Connect

    Hotta, T.; Bandoh, T. . Hitachi Research Lab.); Hotta, A.; Nakano, T. ); Iwamoto, S.; Adachi, S. )

    1990-06-01

    A custom 529K-transistor microprocessor with a five-stage pipeline has been implemented on a 12.98-mm{sup 2} die. Employing BiCMOS macrocells, a 32-b execution unit, extendible ROM, RAM a PLL clock generator with bipolar drivers, and sense circuits, a peak performance of 70 MIPS is achieved. Power consumption is 2.1 W at 40 MHz.

  19. Superradiance on the mHz linewidth clock transition in 87Sr

    NASA Astrophysics Data System (ADS)

    Norcia, Matthew; Winchester, Matthew; Cline, Julia; Thompson, James

    2016-05-01

    In this talk, I will discuss our recent experimental explorations of superradiant emission from the mHz linewidth clock transition in an ensemble of cold 87 Sr atoms confined within a high-finesse optical cavity. Recent proposals suggest that superradiant lasers based on such dipole-forbidden transitions in alkaline earth atoms could achieve linewidths below the current state of the art, with reduced sensitivity to environmental perturbations.

  20. Frequency domain interferometry using the 1290 MHz Soendre Stromfjord radar: First results

    NASA Astrophysics Data System (ADS)

    Palmer, Robert D.; Larsen, Miguel F.; Heinselman, C. J.; Mikkelsen, I. S.

    1993-08-01

    First results from the implementation of frequency domain interferometry (FDI) using an L-band frequency of 1290 MHz are presented. The experiment was conducted in September 1991 using the radar facility located in Soendre Stromford, Greenland. The spectra and the correlation functions obtained from the FDI data are compared to previous results at other frequencies. The data show the Soendre Stromford radar is providing reliable wind measurements in the lower atmosphere and that FDI can be implemented at L-band.

  1. A microprocessor-controlled phase-measurement system for 2856-MHz pulses

    NASA Astrophysics Data System (ADS)

    Fox, J. D.; Schwarz, H.

    1982-04-01

    A computer controlled phase detection system used to measure and stablize the phase of high power RF pulses in the two mile Stanford Linear Accelerator has been developed. This system measures the phase of a 1 micro sec 2856 MHz 50 MW RF pulse with respect to a CW reference signal at the same frequency at a 180 Hz rate with 0.2 deg resolution.

  2. 47 CFR 80.1061 - Special requirements for 406.0-406.1 MHz EPIRB stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... specified in § 80.1101(c)(5). (b) The 406.0-406.1 EPIRB must contain as an integral part a “homing” beacon... document described in paragraph (a) of this section. The 121.500 MHz “homing” beacon must have a continuous... the EPIRB identification code addressed to: NOAA/SARSAT Beacon Registration, E/SP3, Federal Building...

  3. 47 CFR 80.1061 - Special requirements for 406.0-406.1 MHz EPIRB stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... specified in § 80.1101(c)(5). (b) The 406.0-406.1 EPIRB must contain as an integral part a “homing” beacon... document described in paragraph (a) of this section. The 121.500 MHz “homing” beacon must have a continuous... the EPIRB identification code addressed to: NOAA/SARSAT Beacon Registration, E/SP3, Federal Building...

  4. 47 CFR 80.1061 - Special requirements for 406.0-406.1 MHz EPIRB stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... specified in § 80.1101(c)(5). (b) The 406.0-406.1 EPIRB must contain as an integral part a “homing” beacon... document described in paragraph (a) of this section. The 121.500 MHz “homing” beacon must have a continuous... the EPIRB identification code addressed to: NOAA/SARSAT Beacon Registration, E/SP3, Federal Building...

  5. Effect of 2450 MHz microwave radiation on the ultrastructure of snail neurons

    SciTech Connect

    Arber, S.L.; Neilly, J.P.; Lin, J.C.; Kriho, V.

    1986-01-01

    An electron microscopical study of snail neurons was undertaken to verify whether any ultrastructural alterations accompany microwave-induced electrophysiological changes observed in these neurons. Subesophageal ganglia from Helix aspersa snails were exposed to 2450 MHz microwave radiation in vitro at SAR 12.9 mW/g for 60 minutes. It was found that exposure at 21 degrees C causes minor changes in Golgi complexes and slight swelling of the endoplasmic reticulum.

  6. Plasma Response to the Application of 30 MHz RF Power in the NSTX Device

    SciTech Connect

    J.R. Wilson; R.E. Bell; S. Bernabei; J.C. Hosea; B.P. LeBlanc; T.K. Mau; J. Menard; M. Ono; F. Paoletti; R. Pinsker; C.K. Phillips; A. Rosenberg; P.M. Ryan; S. Sabbagh; D. Stutman; D.W. Swain; J.B. Wilgen; Y. Takase

    2001-05-08

    Radio-frequency power at 30 MHz has been applied in a variety of situations to National Spherical Torus Experiment (NSTX) plasmas. The response of the plasma is observed in order to study both the physics of High Harmonic Fast Wave (HHFW) heating and as a tool to extend the performance of NSTX plasmas. In this paper we will discuss the progress made to date towards these goals.

  7. Measurements of Partial Reflections at 3.18 Mhz Using the CW Radar Technique

    NASA Technical Reports Server (NTRS)

    Priese, J.; Singer, W.

    1984-01-01

    An equipment for measuring partial reflections using the FM-CW-radar principle at 3.18 MHz, installed at the Ionospheric Observatory Juliusruh of the CISTP (HHI), is described. The linear FM-chirp of 325 kHz bandwidth is Gaussian-weighted in amplitude and gives a height resolution of 1.5 km (chirp length is 0.6 sec). Preliminary results are presented for the first observation period in winter 1982/83.

  8. 2800 MHz Solar Radio Bursts: A Statistical Analysis of 40 years of Data

    NASA Astrophysics Data System (ADS)

    Balachandran, B.; Lanzerotti, L. J.; Gary, D. E.

    2001-12-01

    The daily values of solar flux and radio bursts at 2800 MHz (10.7 cm wavelength) are known to be closely related to various manifestations of solar activity. The flux values, which vary slowly with time, have long been used as indicators of solar activity. Also, the number of radio bursts shows a variation with the phase of the solar cycle. The close relationships between the 2800 MHz bursts, the associated flares and geophysical phenomena such as shortwave fadeouts have been studied extensively and were established as early as the 1960s. Therefore, a constant monitoring of the Sun at this frequency would enable us to forecast the terrestrial disturbances following the solar activity. Moreover, a detailed study based on past data would help understand solar activity phenomena as well as the origin of these burst events. In the present analysis, we are revisiting some of these points by carrying out an analysis of 40 year data of solar radio bursts with special emphasis on 2800 MHz bursts. A scatter plot of the intensity vs duration shows that the distribution is not completely random but is double--pronged. This result is consistent with earlier works (e.g., Covington, 1959). The two-pronged distribution suggests the existence of two distinct types of burst events: impulsive and gradual rise and fall. The mechanisms that cause the emission of the two types of bursts are also different: the former due to nonthermal processes and the latter due to thermal processes. Our present analysis shows that the intensity--duration plot has a significant variation with the phase of the solar cycle. In addition to this, we present the behaviour of risetime vs duration as well as the frequency distribution of peak flux of these events. The analysis has also been extended to high frequency (> 10 GHz) bursts and the behaviour is contrasted to that of 2800 MHz bursts.

  9. Design of a 325 MHz half wave resonator prototype at IHEP

    NASA Astrophysics Data System (ADS)

    Zhang, Xin-Yin; Pan, Wei-Min; Wang, Guang-Wei; Xu, Bo; Zhao, Guang-Yuan; He, Fei-Si; Li, Zhong-Quan; Ma, Qiang; Dai, Jin; Chen, Xu; Mi, Zheng-Hui; Sha, Peng; Lin, Hai-Ying; Wang, Qun-Yao; Liu, Ya-Ping; Xue, Zhou; Huang, Xuan-Fang; Wang, Mu-Yuan; Sun, Yi

    2016-08-01

    A 325 MHz β = 0.14 superconducting half-wave resonator prototype has been developed at the Institute of High Energy Physics, Beijing, which can be applied in the low energy section of continuous wave high current proton linear accelerators. The electromagnetic design, multipacting simulation, mechanical optimization and fabrication are introduced in detail. Test results at room temperature and 4.2 K, and a comparison between measured and simulated results, are analyzed in this paper.

  10. Type IIIb bursts and their fine structure in frequency band 18-30 MHz

    NASA Astrophysics Data System (ADS)

    Melnik, V. N.; Rucker, H. O.; Konovalenko, A. A.; Shevchuk, N. V.; Abranin, E. P.; Dorovskyy, V. V.; Lecacheux, A.

    2010-01-01

    This paper deals with Type IIIb bursts, which were observed in the frequency band from 18 to 30 MHz. These bursts have fine frequency structures contrary to usual Type III bursts. The main properties of Type IIIb bursts such as number of striae in a burst, their frequency drift rates, durations, frequency widths of stria, emission fluxes are presented. It is also shown that parameters of stria bursts depend on the position of active areas on the solar disk.

  11. Exposure to 1800 MHz radiofrequency radiation impairs neurite outgrowth of embryonic neural stem cells.

    PubMed

    Chen, Chunhai; Ma, Qinlong; Liu, Chuan; Deng, Ping; Zhu, Gang; Zhang, Lei; He, Mindi; Lu, Yonghui; Duan, Weixia; Pei, Liping; Li, Min; Yu, Zhengping; Zhou, Zhou

    2014-05-29

    A radiofrequency electromagnetic field (RF-EMF) of 1800 MHz is widely used in mobile communications. However, the effects of RF-EMFs on cell biology are unclear. Embryonic neural stem cells (eNSCs) play a critical role in brain development. Thus, detecting the effects of RF-EMF on eNSCs is important for exploring the effects of RF-EMF on brain development. Here, we exposed eNSCs to 1800 MHz RF-EMF at specific absorption rate (SAR) values of 1, 2, and 4 W/kg for 1, 2, and 3 days. We found that 1800 MHz RF-EMF exposure did not influence eNSC apoptosis, proliferation, cell cycle or the mRNA expressions of related genes. RF-EMF exposure also did not alter the ratio of eNSC differentiated neurons and astrocytes. However, neurite outgrowth of eNSC differentiated neurons was inhibited after 4 W/kg RF-EMF exposure for 3 days. Additionally, the mRNA and protein expression of the proneural genes Ngn1 and NeuroD, which are crucial for neurite outgrowth, were decreased after RF-EMF exposure. The expression of their inhibitor Hes1 was upregulated by RF-EMF exposure. These results together suggested that 1800 MHz RF-EMF exposure impairs neurite outgrowth of eNSCs. More attention should be given to the potential adverse effects of RF-EMF exposure on brain development.

  12. Background-free broadband CARS spectroscopy from a 1-MHz ytterbium laser.

    PubMed

    Kumar, Vikas; Osellame, R; Ramponi, R; Cerullo, G; Marangoni, M

    2011-08-01

    We introduce a novel configuration for broadband, time-resolved CARS spectroscopy/microscopy in which pump, Stokes and probe pulses are all derived from a single femtosecond Yb:KYW laser. The 1-MHz repetition rate of the system allows very intense CARS signals to be obtained over short acquisition times, while a delayed probe pulse ensures an efficient non-resonant background suppression.

  13. Test results of a 90 MHZ integrated circuit sixteen channel analog pipeline for SSC detector calorimetry

    SciTech Connect

    Kleinfelder, S.A.; Levi, M.; Milgrome, O.

    1990-10-01

    A sixteen channel analog transient recorder with 128 cells per channel has been fabricated as an integrated circuit and tested at speeds of up to 90 MHz. The circuit uses a switched capacitor array technology to achieve a simultaneous read and write capability and twelve bit dynamic range. The high performance of this part should satisfy the demanding electronics requirements of calorimeter detectors at the SSC. The circuit parameters and test results are presented. 2 refs., 3 figs., 1 tab.

  14. [The biological activity of a decameter-range electromagnetic field with a frequency of 24 MHz].

    PubMed

    Bezdol'naia, I S; Dumanskiĭ, Iu D; Smolia, A L

    1991-03-01

    A study of behavioural reactions indicates that the effect of 24 MHz frequencies of the electromagnetic field results in changes of the ratio of excitatory and inhibitory processes in the nervous system of white rats with prevalence of inhibitory processes. By the 90-th day of effect of the above factor all changes returned to the initial level. This indicates stability of the adaptative reactions of the integrative level of the nervous system to the acting factor. PMID:2042349

  15. Oxidative and genotoxic effects of 900 MHz electromagnetic fields in the earthworm Eisenia fetida.

    PubMed

    Tkalec, Mirta; Stambuk, Anamaria; Srut, Maja; Malarić, Krešimir; Klobučar, Göran I V

    2013-04-01

    Accumulating evidence suggests that exposure to radiofrequency electromagnetic field (RF-EMF) can have various biological effects. In this study the oxidative and genotoxic effects were investigated in earthworms Eisenia fetida exposed in vivo to RF-EMF at the mobile phone frequency (900 MHz). Earthworms were exposed to the homogeneous RF-EMF at field levels of 10, 23, 41 and 120 V m(-1) for a period of 2h using a Gigahertz Transversal Electromagnetic (GTEM) cell. At the field level of 23 V m(-1) the effect of longer exposure (4h) and field modulation (80% AM 1 kHz sinusoidal) was investigated as well. All exposure treatments induced significant genotoxic effect in earthworms coelomocytes detected by the Comet assay, demonstrating DNA damaging capacity of 900 MHz electromagnetic radiation. Field modulation additionally increased the genotoxic effect. Moreover, our results indicated the induction of antioxidant stress response in terms of enhanced catalase and glutathione reductase activity as a result of the RF-EMF exposure, and demonstrated the generation of lipid and protein oxidative damage. Antioxidant responses and the potential of RF-EMF to induce damage to lipids, proteins and DNA differed depending on the field level applied, modulation of the field and duration of E. fetida exposure to 900 MHz electromagnetic radiation. Nature of detected DNA lesions and oxidative stress as the mechanism of action for the induction of DNA damage are discussed.

  16. Identification of the anatomical elements used in periodontal diagnosis on 40 MHz periodontal ultrasonography.

    PubMed

    Chifor, Radu; Badea, Mîndra Eugenia; Hedeşiu, Mihaela; Chifor, Ioana

    2015-01-01

    Gingival inflammation is highly prevalent among adult populations in all regions of the world. High rates of chronic periodontitis have been reported worldwide. The methods for assessing the gingival inflammation and periodontal disease would need more precision and less user-dependence. The aim of this study consists in identifying the information for diagnosis and staging of periodontal disease using 40 MHz periodontal ultrasonography. Our in vivo study has been made on 49 teeth of 10 patients with marginal periodontal disease. Standard clinical and radiological periodontal examinations were performed. Afterwards the results were compared with the information obtained from images recorded with Ultrasonix SonoTouch used at 40 MHz. On the ultrasound images, were performed very accurate measurements between the cortical bone and the cement-enamel junction or the root wall compared with the measurements made on intraoral digital radiographs. Those measurements could be used to diagnose the bone resorption. In order to monitor the gingival inflammation could be recorded the width of the attached gingival mucosa and the height of the gingival margin on ultrasound images. 40 MHz periodontal ultrasonography is a reliable imagistic method for identifying the necessary anatomical elements in order to make an accurate periodontal diagnosis for the examined area.

  17. 250 MHz/GHz scintillation parameters in the equatorial, polar, and auroral environments. Environmental research papers

    SciTech Connect

    Basu; MacKenzie, E.; Basu; Costa, E.; Fougere, P.F.

    1986-03-28

    Ionospheric scintillation effects encountered in the equatorial-anomaly crest, polar-cap, and auroral regions have been contrasted to provide information for the design and evaluation of the performance of satellite communication links in these regions. The equatorial-anomaly region is identified as the most-disturbed irregularity environment where the amplitude and phase structures of VHF/L-band scintillations are primarily dictated by the strength of scattering rather than ionospheric motion. In the anomaly region, the spectra of intense amplitude scintillations at VHF and L-band are characterized by uniform power spectral density from the lowest frequency (10 MHz) to 4 Hz at VHF and to 1 Hz at L-band and steep rolloff at higher fluctuation frequencies with power law indices of -5 to 07. Such structures are compatible with intensity decorrelation times of 0.1 and 0.3 sec at VHF and L-band frequencies, respectively. The phase spectra are described by power-law variation of psd with frequency with typical spectral indices of -2. 4. The strong scattering at VHF induces extreme phase rates of 200 deg. in 0.1 sec. The 90th percentile values of rms phase deviation at 250 MHz with 100-sec detrend are found to be 16 rads in the early evening hours whereas amplitude scintillation can cover the entire dynamic range of 30 dB not only at 250 MHz but at L-band as well.

  18. Human serum albumin adsorption study on 62-MHz miniaturized quartz gravimetric sensors.

    PubMed

    Kao, Ping; Patwardhan, Ashish; Allara, David; Tadigadapa, Srinivas

    2008-08-01

    We have designed and fabricated 25-microm-thick quartz resonators operating at a fundamental resonance frequency of approximately 62 MHz. The results show a substantial increase in the mass sensitivity compared to single monolithic commercial resonators operating at lower frequencies in the approximately 5-10-MHz range. The overall performance of the micromachined resonators is demonstrated for the example of human serum albumin protein adsorption from aqueous buffer solutions onto gold electrodes functionalized with self-assembled monolayers. The results show a saturation adsorption frequency change of 6.8 kHz as opposed to 40 Hz for a commercial approximately 5-MHz sensor under identical loading conditions. From the analysis of the adsorption isotherm, the equilibrium adsorption constant of the adsorption of the protein layer was found to be K = 8.03 x 10(6) M(-1), which is in agreement with the values reported in the literature. The high sensitivity of the miniaturized QCM devices can be a significant advantage in both vapor and solution adsorption analyses.

  19. In vitro acoustic characterization of three phospholipid ultrasound contrast agents from 12 to 43 MHz.

    PubMed

    Sun, Chao; Sboros, Vassilis; Butler, Mairead B; Moran, Carmel M

    2014-03-01

    The acoustic properties of two clinical (Definity, Lantheus Medical Imaging, North Billerica, MA, USA; SonoVue, Bracco S.P.A., Milan, Italy) and one pre-clinical (MicroMarker, untargeted, Bracco, Geneva, Switzerland; VisualSonics, Toronto, ON, Canada) ultrasound contrast agent were characterized using a broadband substitution technique over the ultrasound frequency range 12-43 MHz at 20 ± 1°C. At the same number concentration, the acoustic attenuation and contrast-to-tissue ratio of the three native ultrasound contrast agents are comparable at frequencies below 30 MHz, though their size distributions and encapsulated gases and shells differ. At frequencies above 30 MHz, native MicroMarker has higher attenuation values and contrast-to-tissue ratios than native Definity and SonoVue. Decantation was found to be an effective method to alter the size distribution and concentration of native clinical microbubble populations, enabling further contrast enhancement for specific pre-clinical applications.

  20. Compact 400-Mhz Half-Wave Spoke Resonator Crab Cavitiy for the LHC Update

    SciTech Connect

    Li, Zenghai; Xiao, Liling; Ng, Cho; Markiewicz, Thomas; /SLAC

    2010-08-26

    Crab cavities are proposed for the LHC upgrade to improve the luminosity. There are two possible crab cavity installations for the LHC upgrade: the global scheme at Interaction Region (IR) 4 where the beam-beam separation is about 420-mm, and the local scheme at the IR5 where the beam-beam separation is only 194-mm. One of the design requirements as the result of a recent LHC-Crab cavity workshop is to develop a 400-MHz cavity design that can be utilized for either the global or local schemes at IR4 or IR5. Such a design would offer more flexibility for the final upgrade installation, as the final crabbing scheme is yet to be determined, and save R&D cost. The cavity size of such a design, however, is limited by the beam-beam separation at IR5 which can only accommodate a cavity with a horizontal size of about 145-mm, which is a design challenge for a 400-MHz cavity. To meet the new design requirements, we have developed a compact 400-MHz half-wave spoke resonator (HWSR) crab cavity that can fit into the tight spaces available at either IR4 or IR5. In this paper, we present the optimization of the HWSR cavity shape and the design of HOM, LOM, and SOM couplers for wakefield damping.

  1. The Expansion of Arecibo in Summer 2008: A Receiver at 600-1200 MHz

    NASA Astrophysics Data System (ADS)

    Jones, Kristen; Rajagopalan, G.; Whitlow, D.

    2009-01-01

    The purpose of this project is to investigate the radio frequency interference (RFI) environment seen through the Arecibo telescope and recommend necessary limits for a cooled receiver in the 600-1200 MHz regime. Preliminary discriminatory measurements were made using the Hilltop RFI Monitoring system. Strong TV and cell phone signals dominate the band from 450 to 1200 MHz. We seek to overcome this RFI for a number of reasons. It is feasible that the dish will see less troublesome RFI than the Hilltop Monitoring sees. Additionally, this region is astronomically essential, as it is ideal for both pulsar research and high z HI studies. We have constructed an antenna and receiver optimized in the 600-1200 MHz band and have installed them in the Gregorian Dome. We are currently working to focus and calibrate the receiver and to produce spectra across the band from sample regions of the entire Arecibo beam. This information will guide the limits and filters necessary to make a cooled receiver functional in this useful region. We graciously thank the National Science Foundation's Research Experience for Undergraduates program for funding this research.

  2. Untersuchung der Störwirkung von LTE auf SRD Anwendungen bei 868 MHz

    NASA Astrophysics Data System (ADS)

    Welpot, M.; Wunderlich, S.; Gaspard, I.

    2014-11-01

    Moderne Hausautomatisierungssysteme, Alarmanlagen oder auch Funk-Zugangssysteme in Haus und Automobil setzen auf frei nutzbare Frequenzen in ISM/SRD-Bändern. Die rasante Zunahme an privaten und kommerziell genutzten Applikationen im SRD-Band bei 868 MHz und der Ausbau der LTE-Mobilfunknetze im Frequenzbereich unterhalb von 1 GHz ("Digital Dividend") wirft zunehmend die Frage nach der Funkverträglichkeit dieser Systeme untereinander auf. Während die SRD-Funkmodule auf eine geringe Sendeleistung von ~ +14 dBm beschränkt sind (Ralf and Thomas, 2009), beträgt die maximale LTE-Sendeleistung im Uplink nach (ETSI-Norm, 2011) +23 dBm. Zusammen mit der Einführung von LTE im Frequenzbereich unterhalb 1 GHz als DSL-Ersatz vor allem in ländlichen Gebieten, ergibt sich damit als mögliches Störszenario, dass durch die Aussendung des LTE-Endgerätes im Bereich von ca. 850 MHz die SRD-Funkverbindungen bei 868 MHz insbesondere dann gestört werden, wenn die Antennen beider Funksysteme räumlich nahe zueinander angeordnet sind und folglich nur eine geringe zusätzliche Entkopplung der Systeme bieten. In der vorliegenden Arbeit wird das LTE-Störpotential auf SRD-Empfänger praxisnah untersucht.

  3. Performance of an LPD prototype detector at MHz frame rates under Synchrotron and FEL radiation

    NASA Astrophysics Data System (ADS)

    Koch, A.; Hart, M.; Nicholls, T.; Angelsen, C.; Coughlan, J.; French, M.; Hauf, S.; Kuster, M.; Sztuk-Dambietz, J.; Turcato, M.; Carini, G. A.; Chollet, M.; Herrmann, S. C.; Lemke, H. T.; Nelson, S.; Song, S.; Weaver, M.; Zhu, D.; Meents, A.; Fischer, P.

    2013-11-01

    A MHz frame rate X-ray area detector (LPD — Large Pixel Detector) is under development by the Rutherford Appleton Laboratory for the European XFEL. The detector will have 1 million pixels and allows analogue storage of 512 images taken at 4.5 MHz in the detector front end. The LPD detector has 500 μm thick silicon sensor tiles that are bump bonded to a readout ASIC. The ASIC's preamplifier provides relatively low noise at high speed which results in a high dynamic range of 105 photons over an energy range of 5-20 keV. Small scale prototypes of 32 × 256 pixels (LPD 2-Tile detector) and 256 × 256 pixels (LPD supermodule detector) are now available for X-ray tests. The performance of prototypes of the detector is reported for first tests under synchrotron radiation (PETRA III at DESY) and Free-Electron-Laser radiation (LCLS at SLAC). The initial performance of the detector in terms of signal range and noise, radiation hardness and spatial and temporal response are reported. The main result is that the 4.5 MHz sampling detection chain is reliably working, including the analogue on-chip memory concept. The detector is at least radiation hard up to 5 MGy at 12 keV. In addition the multiple gain concept has been demonstrated over a dynamic range to 104 at 12 keV with a readout noise equivalent to < 1 photon rms in its most sensitive mode.

  4. Spreading dynamics of a partially wetting water film atop a MHz substrate vibration

    SciTech Connect

    Altshuler, Gennady; Manor, Ofer

    2015-10-15

    A MHz vibration, or an acoustic wave, propagating in a solid substrate may support the convective spreading of a liquid film. Previous studies uncovered this ability for fully wetting silicon oil films under the excitation of a MHz Rayleigh surface acoustic wave (SAW), propagating in a lithium niobate substrate. Partially wetting de-ionized water films, however, appeared immune to this spreading mechanism. Here, we use both theory and experiment to reconsider this situation and show partially wetting water films may spread under the influence of a propagating MHz vibration. We demonstrate distinct capillary and convective (vibrational/acoustic) spreading regimes that are governed by a balance between convective and capillary mechanisms, manifested in the non-dimensional number θ{sup 3}/We, where θ is the three phase contact angle of the liquid with the solid substrate and We ≡ ρU{sup 2}H/γ; ρ, γ, H, and U are the liquid density, liquid/vapour surface tension, characteristic film thickness, and the characteristic velocity amplitude of the propagating vibration on the solid surface, respectively. Our main finding is that the vibration will support a continuous spreading motion of the liquid film out of a large reservoir if the convective mechanism prevails (θ{sup 3}/We < 1); otherwise (θ{sup 3}/We > 1), the dynamics of the film is governed by the capillary mechanism.

  5. [Influence of 900 MHz frequency electromagnetic radiation on some blood indices].

    PubMed

    Badzhinian, S A; Malakian, M G; Egiazarian, D E; Agdzhoian, R L; Abramian, L E

    2013-01-01

    The paper represents the results of research of some functional indices of blood plasma and erythrocytes in rats obtained on days 1 and 5 after exposure of the organism to low intensive electromagnetic irradiation (EMI) with 900 MHz frequency using the following two irradiation schemes: single 2 h/1 day and fractional 0.5 h/4 days. According to the data obtained, a significant increase of lipid peroxidation (LPO) intensity is registered in animal erythrocyte membranes after the influence of 900 MHz frequency EMI irrespective of the scheme applied. Inhibition of the activity of low-molecular non-enzymatic water-soluble blood antioxidants and enhancement of blood plasma LPO processes is observed on the background of a single prolonged exposure. Stimulation of the antioxidant activity with an abrupt decrease in the blood LPO activity takes place after exposure to fractional irradiation. Single long-lasting exposure, rather than intermittent shortterm exposure to 900 MHz frequency EMI facilitates the appearance of shifts in the activity of Ca(2+)-dependent K(+)-channels of erythrocytes and hyperpolarization of erythrocytes membranes.

  6. Ultrasonic imaging using air-coupled P(VDF/TrFE) transducers at 2 MHz.

    PubMed

    Takahashi, Sadayuki; Ohigashi, Hiroji

    2009-05-01

    A reflection non-contact ultrasonic microscope system working both in amplitude and phase difference modes at 2 MHz has been developed using an air-coupled concave transducer made of piezoelectric polymer films of poly(vinylidene fluoride/trifluoroethylene) [P(VDF/TrFE)]. The transducer is composed of three 95 microm-thick P(VDF/TrFE) films stacked together, each of which is activated electrically in parallel by a driving source. The transducer has a wide aperture angle of 140 degrees and a focal length of 10mm. The measured two-way transducer insertion loss is 80 dB at 1.83 MHz. Despite 20 dB higher insertion loss than that estimated from Mason's equivalent circuit, we have obtained clear amplitude acoustic images of a coin with transverse resolution of 150 microm, and clear phase difference acoustic images of the rough surface of a paper currency bill with depth resolution of sub-micrometer. Using two planar transducers of P(VDF/TrFE), we have also successfully measured in through-transmission mode the sound velocity and absorption of a 3mm-thick silicone-rubber plate. The present study proves that, owing to its low acoustic impedance and flexibility, P(VDF/TrFE) piezoelectric film is very useful for high frequency acoustic imaging in air in the MHz range. PMID:19215951

  7. Development of lead-free single-element ultrahigh frequency (170 – 320 MHz) ultrasonic transducers

    PubMed Central

    Lam, Kwok Ho; Ji, Hong Fen; Zheng, Fan; Ren, Wei; Zhou, Qifa; Shung, K. Kirk

    2013-01-01

    This paper presents the design, fabrication and characterization of single-element ultrahigh frequency (UHF) ultrasonic transducers in which the center frequency ranged from 170 to 320 MHz. The center frequency of > 300 MHz is the highest value of lead-free ceramic ultrasonic transducers ever reported. With concern in the environmental pollution of lead-based materials, the transducer elements presented in this work were lead-free K0.5Na0.5NbO3/Bi0.5Na0.5TiO3 (KNN/BNT) composite thick films. All transducers were evaluated in a pulse-echo arrangement. The measured −6 dB bandwidth of the transducers ranged from 35 to 64 %. With the optimized piezoelectric properties of the composite film, the insertion loss of the UHF transducers was measured and determined to range from −50 to −60 dB. In addition to the pulse-echo measurement, a 6-μm tungsten wire phantom was also imaged with a 205 MHz transducer to demonstrate the imaging capability. The measured −6 dB axial and lateral resolutions were found to be 12 μm and 50 μm, respectively. The transducer performance presented in this work is shown to be better or comparable to previously reported results even though the frequency is much higher. PMID:23485349

  8. Development of lead-free single-element ultrahigh frequency (170-320MHz) ultrasonic transducers.

    PubMed

    Lam, Kwok Ho; Ji, Hong Fen; Zheng, Fan; Ren, Wei; Zhou, Qifa; Shung, K Kirk

    2013-07-01

    This paper presents the design, fabrication and characterization of single-element ultrahigh frequency (UHF) ultrasonic transducers in which the center frequency ranged from 170 to 320MHz. The center frequency of >300MHz is the highest value of lead-free ceramic ultrasonic transducers ever reported. With concern in the environmental pollution of lead-based materials, the transducer elements presented in this work were lead-free K0.5Na0.5NbO3/Bi0.5Na0.5TiO3 (KNN/BNT) composite thick films. All transducers were evaluated in a pulse-echo arrangement. The measured -6dB bandwidth of the transducers ranged from 35% to 64%. With the optimized piezoelectric properties of the composite film, the insertion loss of the UHF transducers was measured and determined to range from -50 to -60dB. In addition to the pulse-echo measurement, a 6μm tungsten wire phantom was also imaged with a 205MHz transducer to demonstrate the imaging capability. The measured -6dB axial and lateral resolutions were found to be 12μm and 50μm, respectively. The transducer performance presented in this work is shown to be better or comparable to previously reported results even though the frequency is much higher.

  9. Temperature regulation in the unrestrained rabbit during exposure to 600-MHz radiofrequency radiation

    SciTech Connect

    Gordon, C.J.; Long, M.D.; Fehlner, K.S.

    1986-01-01

    Six male New Zealand white rabbits were individually exposed to 600-MHz radiofrequency (RF) radiation for 90 min in a waveguide exposure system at an ambient temperature (Ta) of 20 or 30 C. Immediately after exposure, the rabbit was removed from the exposure chamber and its colonic and ear skin temperatures were quickly measured. The whole-body specific absorption rate (SAR) required to increase colonic and ear skin temperature was determined. At a Ta of 20 C, the threshold SAR for elevating colonic and ear skin temperature was 0.64 and 0.26 W/kg, respectively. At a Ta of 30 C, the threshold SARs were slightly less than at 20 C, with values of 0.26 W/kg for elevating colonic temperature and 0.19 W/kg for elevating ear skin temperature. The relationship between heat load and elevation in deep body temperature shown in the study at 600 MHz is similar to past studies that employed much-higher frequencies of RF radiation (2450-2884 MHz).

  10. Sustaining GHz oscillation of carbon nanotube based oscillators via a MHz frequency excitation

    NASA Astrophysics Data System (ADS)

    Motevalli, Benyamin; Taherifar, Neda; Zhe Liu, Jefferson

    2016-05-01

    There have been intensive studies to investigate the properties of gigahertz nano-oscillators based on multi-walled carbon nanotubes (MWCNTs). Many of these studies, however, revealed that the unique telescopic translational oscillations in such devices would damp quickly due to various energy dissipation mechanisms. This challenge remains the primary obstacle against its practical applications. Herein, we propose a design concept in which a GHz oscillation could be re-excited by a MHz mechanical motion. This design involves a triple-walled CNT, in which sliding of the longer inner tube at a MHz frequency can re-excite and sustain a GHz oscillation of the shorter middle tube. Our molecular dynamics (MD) simulations prove this design concept at ˜10 nm scale. A mathematical model is developed to explore the feasibility at a larger size scale. As an example, in an oscillatory system with the CNT’s length above 100 nm, the high oscillatory frequency range of 1.8-3.3 GHz could be excited by moving the inner tube at a much lower frequency of 53.4 MHz. This design concept together with the mechanical model could energize the development of GHz nano-oscillators in miniaturized electro-mechanical devices.

  11. Effects of 900 MHz radiofrequency on corticosterone, emotional memory and neuroinflammation in middle-aged rats.

    PubMed

    Bouji, Marc; Lecomte, Anthony; Hode, Yannick; de Seze, René; Villégier, Anne-Sophie

    2012-06-01

    The widespread use of mobile phones raises the question of the effects of electromagnetic fields (EMF, 900 MHz) on the brain. Previous studies reported increased levels of the glial fibrillary acidic protein (GFAP) in the rat's brain after a single exposure to 900 MHz global system for mobile (GSM) signal, suggesting a potential inflammatory process. While this result was obtained in adult rats, no data is currently available in older animals. Since the transition from middle-age to senescence is highly dependent on environment and lifestyle, we studied the reactivity of middle-aged brains to EMF exposure. We assessed the effects of a single 15 min GSM exposure (900 MHz; specific absorption rate (SAR)=6 W/kg) on GFAP expression in young adults (6 week-old) and middle-aged rats (12 month-old). Brain interleukin (IL)-1β and IL-6, plasmatic levels of corticosterone (CORT), and emotional memory were also assessed. Our data indicated that, in contrast to previously published work, acute GSM exposure did not induce astrocyte activation. Our results showed an IL-1β increase in the olfactory bulb and enhanced contextual emotional memory in GSM-exposed middle-aged rats, and increased plasmatic levels of CORT in GSM-exposed young adults. Altogether, our data showed an age dependency of reactivity to GSM exposure in neuro-immunity, stress and behavioral parameters. Reproducing these effects and studying their mechanisms may allow a better understanding of mobile phone EMF effects on neurobiological parameters.

  12. A COMBINED LOW-RADIO FREQUENCY/X-RAY STUDY OF GALAXY GROUPS. I. GIANT METREWAVE RADIO TELESCOPE OBSERVATIONS AT 235 MHz AND 610 MHz

    SciTech Connect

    Giacintucci, Simona; O'Sullivan, Ewan; Vrtilek, Jan; David, Laurence P.; Mazzotta, Pasquale; Gitti, Myriam; Jones, Christine; Forman, William R.; Raychaudhury, Somak; Ponman, Trevor; Venturi, Tiziana; Athreya, Ramana M.; Clarke, Tracy E.; Murgia, Matteo; Ishwara-Chandra, C. H.

    2011-05-10

    We present new Giant Metrewave Radio Telescope observations at 235 MHz and 610 MHz of 18 X-ray bright galaxy groups. These observations are part of an extended project, presented here and in future papers, which combines low-frequency radio and X-ray data to investigate the interaction between central active galactic nuclei (AGNs) and the intra-group medium (IGM). The radio images show a very diverse population of group-central radio sources, varying widely in size, power, morphology, and spectral index. Comparison of the radio images with Chandra and XMM-Newton X-ray images shows that groups with significant substructure in the X-ray band and marginal radio emission at {approx}>1 GHz host low-frequency radio structures that correlate with substructures in IGM. Radio-filled X-ray cavities, the most evident form of AGN/IGM interaction in our sample, are found in half of the systems and are typically associated with small, low-, or mid-power double radio sources. Two systems, NGC5044 and NGC4636, possess multiple cavities, which are isotropically distributed around the group center, possibly due to group weather. In other systems the radio/X-ray correlations are less evident. However, the AGN/IGM interaction can manifest itself through the effects of the high-pressure medium on the morphology, spectral properties, and evolution of the radio-emitting plasma. In particular, the IGM can confine fading radio lobes in old/dying radio galaxies and prevent them from dissipating quickly. Evidence for radio emission produced by former outbursts that co-exist with current activity is found in six groups of the sample.

  13. SUPPLEMENTARY COMPARISON: Bilateral Supplementary Comparison P1-APMP.EM.RF-S4: Calibration factor of thermistor mount power sensors: in Type-N, 30 MHz 3000 MHz

    NASA Astrophysics Data System (ADS)

    Zhang, Tieren; Hall, Blair

    2004-01-01

    This is the final report on the APMP bilateral supplementary comparison in RF power measurement P1-APMP.EM.RF-S4. The purpose of the comparison is to determine the level of consistency of calibration results given by two national standards laboratories. This is a comparison of one of the high-frequency key quantities. The comparison protocol was based on that used in the key comparison CCEM.RF-K8; however, the frequency points differ. One of the participants, the National Measurement Laboratory, also took part in CCEM.RF-K8. The travelling standard is a Hewlett-Packard 8478B thermistor mount, with a type-N male RF connector. The calibration factor is determined at a number of frequencies between 30 MHz and 3000 MHz, together with an appropriate statement of uncertainty. Measurements have been made at a nominal power level of 1 mW. The value of the reflection coefficient is also determined, as it is needed for the uncertainty calculation. The pilot laboratory was the National Measurement Laboratory, in Australia, and the comparison coordinator was the Measurement Standards Laboratory of New Zealand. This report contains a brief description of the measurement set-ups at each laboratory and a summary of the associated uncertainty budgets. The actual measurements from each laboratory are presented as they appear in calibration certificates from the respective laboratories. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the APMP, according to the provisions of the Mutual Recognition Arrangement (MRA).

  14. 76 FR 49364 - Fixed and Mobile Services in the Mobile Satellite Service Bands at 1525-1559 MHz and 1626.5-1660...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ..., published at 76 FR 31252, May 31, 2011. This is a summary of the Commission's document, Report No. 2932... COMMISSION 47 CFR Parts 1, 2, and 25 Fixed and Mobile Services in the Mobile Satellite Service Bands at 1525... Satellite Service Bands at 1525-1559 MHz and 1626.5-1660.5 MHz, 1610-1626.5 MHz and 2483.5-2500 MHz,...

  15. 76 FR 31252 - Fixed and Mobile Services in the Mobile Satellite Service Bands at 1525-1559 MHz and 1626.5-1660...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-31

    ....5-2500 MHz, and the L-band from 1525-1559 MHz and 1626.5-1660.5 MHz. 75 FR 49871 (August 16, 2010... capability to serve important needs, such as rural access and disaster recovery. 75 FR 49871 (August 16, 2010... then provide wireless services consistent with the underlying license authorization. 68 FR...

  16. 47 CFR 27.1111 - Relocation of fixed microwave service licensees in the 2110-2150 and 2160-2200 MHz bands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Relocation of fixed microwave service licensees... Incumbents § 27.1111 Relocation of fixed microwave service licensees in the 2110-2150 and 2160-2200 MHz bands... of incumbent fixed microwave service licensees in the 2110-2150 MHz and 2160-2200 MHz...

  17. 78 FR 19424 - Service Rules for the 698-746, 747-762 and 777-792 MHz Bands; Revision of the Commission's Rules...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-01

    ... spectrum aggregation limits at the initial licensing stages of the 700 MHz Band. Further, the Commission...-792 MHz Bands; Revision of the Commission's Rules To Ensure Compatibility With Enhanced 911 Emergency..., relating to the 698-806 MHz Band, including decisions regarding performance requirements, the auction...

  18. Update on the CeC PoP 704 MHz 5-cell cavity cryomodule design and fabrication

    SciTech Connect

    Brutus, J. C.; Belomestnykh, S.; Ben-Zvi, I.; Grimm, T.; Huang, Y.; Jecks, R.; Kelly, M.; Litvinenko, V.; Pinayev, I.; Reid, T.; Skaritka, J.; Snydstrup, L.; Than, R.; Tuozzolo, J.; Xu, W.; Yancey, J.; Gerbick, S.

    2015-05-03

    A 5-cell SRF cavity operating at 704 MHz will be used for the Coherent Electron Cooling Proof of Principle (CeC PoP) system under development for the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. The CeC PoP experiment will demonstrate the new technique of cooling proton and ion beams that may increase the beam luminosity in certain cases, by as much as tenfold. The 704 MHz cavity will accelerate 2 MeV electrons from a 112 MHz SRF gun up to 22MeV. This paper provides an overview of the design, the project status and schedule of the 704 MHz 5-cell SRF for CeC PoP experiment.

  19. 76 FR 1158 - Auction of 700 MHz Band Licenses Scheduled for July 19, 2011; Comment Sought on Competitive...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-07

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION Auction of 700 MHz Band Licenses Scheduled for July 19, 2011; Comment Sought on Competitive Bidding Procedures for Auction 92 AGENCY: Federal Communications Commission. ACTION: Notice. ]...

  20. Body heating induced by sub-resonant (350 MHz) microwave irradiation: Cardiovascular and respiratory responses in anesthetized rats

    SciTech Connect

    Jauchem, J.R.; Frei, M.R.

    1997-06-01

    These experiments were designed to investigate the effects of sub-resonant microwave (MW) exposure (350 MHz, E orientation, average power density 38 mW/cm{sup 2}, average whole-body specific absorption rate 13.2 W/kg) on selected physiological parameters. The increase in peripheral body temperature during 350 MHz exposure was greater than that in earlier experiments performed at 700 MHz (resonance). Heart rate and mean arterial blood pressure were significantly elevated during a 1 C increase in colonic temperature due to 350 MHz exposure; respiratory rate showed no significant change. The results are consistent with other investigator`s reports comparing sub-resonance exposures with those at resonance and above.

  1. Observations of 0.3 kHz to 500 MHz Periodic Oscillations in the PFRC-2 Device

    NASA Astrophysics Data System (ADS)

    Ho, Emily; Swanson, Charles; Cohen, Sam; PFRC Team

    2015-11-01

    With a capacitively coupled 27-MHz RF system supplying up to 400 W of power in one end cell, hydrogen plasma was generated in the PFRC-2 device, operating in a tandem mirror mode. Langmuir probes were used to measure oscillations in the floating potential in the other PFRC-2 end cell, with a conducting floating boundary slightly downstream of the probe. A fast camera was used to examine visible plasma oscillations in PFRC-2 central cell. At speeds between 5 and 13 kfps, the fast camera showed oscillations below 700 Hz; corresponding peaks were found in the floating potential spectrum. Radial probe measurements suggest it to be a bursting m=0 mode. The probe data also showed large periodic MHz-range oscillations, at 27 MHz and its first 10 harmonics. A broad peak is near 300 MHz, close to the central-cell electron cyclotron frequency. The frequency of FFT peaks near 1 MHz, in the ICRF of the mirror-coil field, varied linearly with the magnetic field strength. These intermodulate with the RF signal, creating sidebands to the 27 MHz peak and its harmonics. We present findings from the fast camera of the rotating magnetic field mode. This work is supported by DOE contract DE-AC02-09CH11466 and the Princeton Environmental Institute.

  2. Phase-locked MHz pulse selector for x-ray sources.

    PubMed

    Förster, Daniel F; Lindenau, Bernd; Leyendecker, Marko; Janssen, Franz; Winkler, Carsten; Schumann, Frank O; Kirschner, Jürgen; Holldack, Karsten; Föhlisch, Alexander

    2015-05-15

    Picosecond x-ray pulses are extracted with a phase-locked x-ray pulse selector at 1.25 MHz repetition rate from the pulse trains of the accelerator-driven multiuser x-ray source BESSY II preserving the peak brilliance at high pulse purity. The system consists of a specially designed in-vacuum chopper wheel rotating with ≈1  kHz angular frequency. The wheel is driven in an ultrahigh vacuum and is levitated on magnetic bearings being capable of withstanding high centrifugal forces. Pulses are picked by 1252 high-precision slits of 70 μm width on the outer rim of the wheel corresponding to a temporal opening window of the chopper of 70 ns. We demonstrate how the electronic phase stabilization of ±2  ns together with an arrival time jitter of the individual slits of the same order of magnitude allows us to pick short single bunch x-ray pulses out of a 200 ns ion clearing gap in a multibunch pulse train as emitted from a synchrotron facility at 1.25 MHz repetition rate with a pulse purity below the shot noise detection limit. The approach is applicable to any high-repetition pulsed radiation source, in particular in the x-ray spectral range up to 10 keV. The opening window in a real x-ray beamline, its stability, as well as the limits of mechanical pulse picking techniques in the MHz range are discussed. PMID:26393715

  3. A 14-bit 40-MHz analog front end for CCD application

    NASA Astrophysics Data System (ADS)

    Jingyu, Wang; Zhangming, Zhu; Shubin, Liu

    2016-06-01

    A 14-bit, 40-MHz analog front end (AFE) for CCD scanners is analyzed and designed. The proposed system incorporates a digitally controlled wideband variable gain amplifier (VGA) with nearly 42 dB gain range, a correlated double sampler (CDS) with programmable gain functionality, a 14-bit analog-to-digital converter and a programmable timing core. To achieve the maximum dynamic range, the VGA proposed here can linearly amplify the input signal in a gain range from -1.08 to 41.06 dB in 6.02 dB step with a constant bandwidth. A novel CDS takes image information out of noise, and further amplifies the signal accurately in a gain range from 0 to 18 dB in 0.035 dB step. A 14-bit ADC is adopted to quantify the analog signal with optimization in power and linearity. An internal timing core can provide flexible timing for CCD arrays, CDS and ADC. The proposed AFE was fabricated in SMIC 0.18 μm CMOS process. The whole circuit occupied an active area of 2.8 × 4.8 mm2 and consumed 360 mW. When the frequency of input signal is 6.069 MHz, and the sampling frequency is 40 MHz, the signal to noise and distortion (SNDR) is 70.3 dB, the effective number of bits is 11.39 bit. Project supported by the National Natural Science Foundation of China (Nos. 61234002, 61322405, 61306044, 61376033), the National High-Tech Program of China (No. 2013AA014103), and the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory (No. ZHD201302).

  4. The toxic effects of mobile phone radiofrequency (940 MHz) on the structure of calf thymus DNA.

    PubMed

    Hekmat, Azadeh; Saboury, Ali Akbar; Moosavi-Movahedi, Ali Akbar

    2013-02-01

    Currently, the biological effects of nonionizing electromagnetic fields (EMFs) including radiofrequency (RF) radiation have been the subject of numerous experimental and theoretical studies. The aim of this study is to evaluate the possible biological effects of mobile phone RF (940 MHz, 15 V/m and SAR=40 mW/kg) on the structure of calf thymus DNA (ct DNA) immediately after exposure and 2 h after 45 min exposure via diverse range of spectroscopic instruments. The UV-vis and circular dichroism (CD) experiments depict that mobile phone EMFs can remarkably cause disturbance on ct DNA structure. In addition, the DNA samples, immediately after exposure and 2 h after 45 min exposure, are relatively thermally unstable compared to the DNA solution, which was placed in a small shielded box (unexposed ct DNA). Furthermore, the exposed DNA samples (the DNA samples that were exposed to 940 MHz EMF) have more fluorescence emission when compared with the unexposed DNA, which may have occurred attributable to expansion of the exposed DNA structure. The results of dynamic light scattering (DLS) and zeta potential experiments demonstrate that RF-EMFs lead to increment in the surface charge and size of DNA. The structure of DNA immediately after exposure is not significantly different from the DNA sample 2 h after 45 min exposure. In other words, the EMF-induced conformational changes are irreversible. Collectively, our results reveal that 940 MHz can alter the structure of DNA. The displacement of electrons in DNA by EMFs may lead to conformational changes of DNA and DNA disaggregation. Results from this study could have an important implication on the health effects of RF-EMFs exposure. In addition, this finding could proffer a novel strategy for the development of next generation of mobile phone.

  5. A 14-bit 40-MHz analog front end for CCD application

    NASA Astrophysics Data System (ADS)

    Jingyu, Wang; Zhangming, Zhu; Shubin, Liu

    2016-06-01

    A 14-bit, 40-MHz analog front end (AFE) for CCD scanners is analyzed and designed. The proposed system incorporates a digitally controlled wideband variable gain amplifier (VGA) with nearly 42 dB gain range, a correlated double sampler (CDS) with programmable gain functionality, a 14-bit analog-to-digital converter and a programmable timing core. To achieve the maximum dynamic range, the VGA proposed here can linearly amplify the input signal in a gain range from ‑1.08 to 41.06 dB in 6.02 dB step with a constant bandwidth. A novel CDS takes image information out of noise, and further amplifies the signal accurately in a gain range from 0 to 18 dB in 0.035 dB step. A 14-bit ADC is adopted to quantify the analog signal with optimization in power and linearity. An internal timing core can provide flexible timing for CCD arrays, CDS and ADC. The proposed AFE was fabricated in SMIC 0.18 μm CMOS process. The whole circuit occupied an active area of 2.8 × 4.8 mm2 and consumed 360 mW. When the frequency of input signal is 6.069 MHz, and the sampling frequency is 40 MHz, the signal to noise and distortion (SNDR) is 70.3 dB, the effective number of bits is 11.39 bit. Project supported by the National Natural Science Foundation of China (Nos. 61234002, 61322405, 61306044, 61376033), the National High-Tech Program of China (No. 2013AA014103), and the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory (No. ZHD201302).

  6. Solar U- and J- Bursts at the Frequencies 10-30MHz

    NASA Astrophysics Data System (ADS)

    Dorovskyy, V. V.; Melnik, V. N.; Konovalenko, A. A.; Abranin, E. P.; Rucker, H. O.; Lecacheux, A.

    2006-08-01

    In the present report we discuss the results of observations of solar U- and J- bursts over the frequency range 10-30MHz, which have been obtained within the framework of an international observational campaign in June - August, 2004 at the radio telescope UTR-2 (Kharkov, Ukraine). We succeed to observe these types of bursts for the first time at such a low frequencies due to combination of large effective area of the radio telescope and high sensitivity of the new back-end. During June - August, 2004 about 30 U- and J- bursts were registered, and only 5 of them were confidently identified as U-bursts that may speak about the relative sparsity of the latter at mentioned frequencies. Both the isolated bursts and their sequences were observed. On average the turning frequencies lay in the range 10-22 MHz that corresponds to the arches heliocentric heights of 1.6-2.2 solar radii. In some sequences the bursts turning frequency was stable that may indicate the arch stability, while in others the turning frequency had tendency to vary from burst to burst. Durations of U- and J- bursts did not differ from those of usual Type III bursts (3-7s), while the drift rates of an ascending arm (on the average -1MHz/ s) was a little bit lower, than those of ordinary Type III bursts in this range. The harmonic structure of U- and J- bursts, and also Jb-J pairs (analogous to IIIb-III pairs) were registered. Also L-shaped bursts (Leblanc and Hoyos, 1985) were recorded. A specific feature of L-shaped bursts is prolonged zero-drift region on their dynamic spectra. The sizes and configurations of the arches were estimated on the base of obtained data. Possible explanations of the observed properties of U- and J- bursts are discussed.

  7. Central FPGA-based destination and load control in the LHCb MHz event readout

    NASA Astrophysics Data System (ADS)

    Jacobsson, R.

    2012-10-01

    The readout strategy of the LHCb experiment is based on complete event readout at 1 MHz. A set of 320 sub-detector readout boards transmit event fragments at total rate of 24.6 MHz at a bandwidth usage of up to 70 GB/s over a commercial switching network based on Gigabit Ethernet to a distributed event building and high-level trigger processing farm with 1470 individual multi-core computer nodes. In the original specifications, the readout was based on a pure push protocol. This paper describes the proposal, implementation, and experience of a non-conventional mixture of a push and a pull protocol, akin to credit-based flow control. An FPGA-based central master module, partly operating at the LHC bunch clock frequency of 40.08 MHz and partly at a double clock speed, is in charge of the entire trigger and readout control from the front-end electronics up to the high-level trigger farm. One FPGA is dedicated to controlling the event fragment packing in the readout boards, the assignment of the farm node destination for each event, and controls the farm load based on an asynchronous pull mechanism from each farm node. This dynamic readout scheme relies on generic event requests and the concept of node credit allowing load control and trigger rate regulation as a function of the global farm load. It also allows the vital task of fast central monitoring and automatic recovery in-flight of failing nodes while maintaining dead-time and event loss at a minimum. This paper demonstrates the strength and suitability of implementing this real-time task for a very large distributed system in an FPGA where no random delays are introduced, and where extreme reliability and accurate event accounting are fundamental requirements. It was in use during the entire commissioning phase of LHCb and has been in faultless operation during the first two years of physics luminosity data taking.

  8. VLA observations of the supernova remnant Puppus A at 327 and 1515 MHz

    NASA Technical Reports Server (NTRS)

    Dubner, G. M.; Braun, R.; Winkler, P. F.; Goss, W. M.

    1991-01-01

    Very Large Array radio images of Puppis A at 327 and 1515 MHz are presented. The observations were performed with the VLA in the C/D and B/C configurations, respectively. The angular resolution is about 77 arcsec x 43 arcsec. The observed radio shell shows signs of interaction between the expanding shock front and the inhomogeneous surrounding medium. An excellent correlation is found between radio and X-ray emission, mainly toward the NE border of the remnant. There is little correspondence between the optical and radio images, suggesting a different origin for the emission. A region of steeper radio spectral index is associated with the highly decelerated eastern periphery.

  9. Bulk Current Injection Testing of Cable Noise Reduction Techniques, 50 kHz to 400 MHz

    NASA Technical Reports Server (NTRS)

    Bradley, Arthur T.; Hare, Richard J.; Singh, Manisha

    2009-01-01

    This paper presents empirical results of cable noise reduction techniques as demonstrated using bulk current injection (BCI) techniques with radiated fields from 50 kHz - 400 MHz. It is a follow up to the two-part paper series presented at the Asia Pacific EMC Conference that focused on TEM cell signal injection. This paper discusses the effects of cable types, shield connections, and chassis connections on cable noise. For each topic, well established theories are compared with data from a real-world physical system.

  10. Front end processing for a 100 MHZ Flash-ADC-System

    SciTech Connect

    Eckerlin, G.; Elsen, E.; Schmitt, H.V.D.; Wagner, A.; Walter, P.V.

    1986-06-01

    An intelligent interface for readout of a high speed (100 MHz), multichannel Flash-ADC System is described. 3072 FADC channels are controlled and read by a system of 34 microprocessors M68000 placed at two different hierarchical levels. In addition to the readout itself, the processors perform a detailed pulse shape analysis necessary for a compact and manageable data format. The purpose of the system is to exploit the good double tract separation and time resolution provided by Flash-ADCs in conjunction with large drift chamber detectors such as JADE at PETRA and OPAL at LEP. Details of the system presently being installed at JADE are reviewed.

  11. VizieR Online Data Catalog: 102.5MHz Survey (Dagkesamanskii+, 2000)

    NASA Astrophysics Data System (ADS)

    Dagkesamanskii, R. D.; Samodurov, V. A.; Lapaev, K. A.

    2000-08-01

    The results of observations on the Large Phased Array of the Lebedev Physical Institute made as part of a survey of northern sky at 102.5 MHz are reported. Survey source lists for declination ranges 27.5-33.5 deg. and 67.5-70.5 deg. are given, together with their coordinates, flux densities and identifications with 4C objects. In total, there are 920 sources with flux densities S(102.5)>=3.0 Jy in the two zones, which cover over 0.73 steradians. (2 data files).

  12. Development and Production of a 201 MHz, 5.0 MW Peak Power Klystron

    SciTech Connect

    Aymar, Galen; Eisen, Edward; Stockwell, Brad; Begum, rasheda; Lenci, Steve; Eisner, Rick; Cesca, Eugene

    2016-01-01

    Communications & Power Industries LLC has designed and manufactured the VKP-8201A, a high peak power, high gain, VHF band klystron. The klystron operates at 201.25 MHz, with 5.0 MW peak output power, 34 kW average output power, and a gain of 36 dB. The klystron is designed to operate between 1.0 MW and 4.5 MW in the linear range of the transfer curve. The klystron utilizes a unique magnetic field which enables the use of a proven electron gun design with a larger electron beam requirement. Experimental and predicted performance data are compared.

  13. JPL 2-to-the-20th-power channel 300 MHz bandwidth digital spectrum analyzer

    NASA Technical Reports Server (NTRS)

    Morris, G. A., Jr.; Wilck, H. C.

    1978-01-01

    A million (two to the 20th power) channel, 300 MHz bandwidth, digital spectrum analyzer was considered. The design, fabrication, and maintenance philosophy of the modular, pipelined, fast fourier transform (FFT) hardware are described. The spectrum analyzer will be used to examine the region from 1.4 GHz to 26 GHz for radio frequency interference which may be harmful to present and future tracking missions of the Deep Space Network. The design has application to the search for extraterrestrial intelligence signals and radio science phenomena.

  14. Simulations of multipacting in the cathode stalk and FPC of 112 MHz superconducting electron gun

    SciTech Connect

    Xin T.; Ben-Zvi, I.; Belomestnykh, S.; Chang, X.; Rao, T.; Skaritka, J.; Wu, Q.; Wang, E.; Liang, X.

    2012-05-20

    A 112 MHz superconducting quarter-wave resonator electron gun will be used as the injector of the Coherent Electron Cooling (CEC) proof-of-principle experiment at BNL. Furthermore, this electron gun can be used for testing of the performance of various high quantum efficiency photocathodes. In a previous paper, we presented the design of the cathode stalks and a Fundamental Power Coupler (FPC). In this paper we present updated designs of the cathode stalk and FPC. Multipacting in the cathode stalk and FPC was simulated using three different codes. All simulation results show no serious multipacting in the cathode stalk and FPC.

  15. A compact 500 MHz 4 kW Solid-State Power Amplifier for accelerator applications

    NASA Astrophysics Data System (ADS)

    Gaspar, M.; Pedrozzi, M.; Ferreira, L. F. R.; Garvey, T.

    2011-05-01

    We present the development of a compact narrow-band Solid-State Power Amplifier (SSPA). We foresee a promising application of solid-state amplifiers specifically in accelerators for new generation synchrotron light sources. Such a new technology has reached a competitive price/performance ratio and expected lifetime in comparison with klystron and IOT amplifiers. The increasing number of synchrotron light sources using 500 MHz as base frequency justifies the effort in the development of the proposed amplifier. Two different techniques are also proposed to improve the control and performance of these new distributed amplification systems which we call, respectively, complete distributed system and forced compression.

  16. Fabrication of the Prototype 201.25 MHz Cavity for a Muon Ionization Cooling Experiment

    SciTech Connect

    R.A. Rimmer; S. Manning; R. Manus; L. Phillips; M. Stirbet; K. Worland; G. Wu; D. Li; R. MacGill; J. Staples; S. Virostek; M. Zisman; K. Taminger; R. Hafley; R. Martin; D. Summers; M. Reep

    2005-05-01

    We describe the fabrication and assembly of the first prototype 201.25 MHz copper cavity for the muon ionization cooling experiment (MICE). This cavity was developed by the US MUCOOL collaboration and will be tested in the new MUCOOL Test Area at Fermilab. We outline the component and subassembly fabrication steps and the various metal forming and joining methods used to produce the final cavity shape. These include spinning, brazing, TIG welding, electron beam welding, electron beam annealing and deep drawing. Some of the methods developed for this cavity are novel and offer significant cost savings over conventional construction methods.

  17. Fabrication of the prototype 201.25 mhz cavity for a muon ionization cooling experiment

    SciTech Connect

    Rimmer, R.A.; Manning, S.; Manus, R.; Phillips, L.; Stirbet, M.; Worland, K.; Wu, G.; Li, D.; MacGill, R.; Staples, J.; Virostek, S.; Zisman, M.S.; Taminger, K.; Hafley, R.; Martin, R.; Summers, D.; Reep, M.

    2005-05-20

    We describe the fabrication and assembly of the first prototype 201. 25 MHz copper cavity for the muon ionization cooling experiment (MICE). This cavity was developed by the US MUCOOL collaboration and will be tested in the new MUCOOL Test Area at Fermilab. We outline the component and subassembly fabrication steps and the various metal forming and joining methods used to produce the final cavity shape. These include spinning, brazing, TIG welding, electron beam welding, electron beam annealing and deep drawing. Some of the methods developed for this cavity are novel and offer significant cost savings over conventional methods.

  18. Buffer Chemical Polishing and RF Testing of the 56 MHz SRF Cavity

    SciTech Connect

    Burrill,A.

    2009-01-01

    The 56 MHz cavity presents a unique challenge in preparing it for RF testing prior to construction of the cryomodule. This challenge arises due to the physical dimensions and subsequent weight of the cavity, and is further complicated by the coaxial geometry, and the need to properly chemically etch and high pressure rinse the entire inner surface prior to RF testing. To the best of my knowledge, this is the largest all niobium SRF cavity to be chemically etched and subsequently tested in a vertical dewar at 4K, and these processes will be the topic of this technical note.

  19. Multipacting Simulation Study for 56 MHz Quarter Wave Resonator using 2D Code

    SciTech Connect

    Naik,D.; Ben-Zvi, I.

    2009-01-02

    A beam excited 56 MHz Radio Frequency (RF) Niobium Quarter Wave Resonator (QWR) has been proposed to enhance RHIC beam luminosity and bunching. Being a RF cavity, multipacting is expected; therefore an extensive study was carried out with the Multipac 2.1 2D simulation code. The study revealed that multipacting occurs in various bands up to peak surface electric field 50 kV/m and is concentrated mostly above the beam gap and on the outer conductor. To suppress multipacting, a ripple structure was introduced to the outer conductor and the phenomenon was successfully eliminated from the cavity.

  20. Ultrasonic Scattering Measurements of a Live Single Cell at 86 MHz

    PubMed Central

    Lee, Changyang; Jung, Hayong; Lam, Kwok Ho; Yoon, Changhan; Shung, K. Kirk

    2016-01-01

    Cell separation and sorting techniques have been employed biomedical applications such as cancer diagnosis and cell gene expression analysis. The capability to accurately measure ultrasonic scattering properties from cells is crucial in making an ultrasonic cell sorter a reality if ultrasound scattering is to be used as the sensing mechanism as well. To assess the performance of sensing and identifying live single cells with high-frequency ultrasound, an 86-MHz lithium niobate press-focused single-element acoustic transducer was used in a high-frequency ultrasound scattering measurement system that was custom designed and developed for minimizing noise and allowing better mobility. Peak-to-peak echo amplitude, integrated backscatter (IB) coefficient, spectral parameters including spectral slope and intercept, and midband fit from spectral analysis of the backscattered echoes were measured and calculated from a live single cell of two different types on an agar surface: leukemia cells (K562 cells) and red blood cells (RBCs). The amplitudes of echo signals from K562 cells and RBCs were 48.25 ± 11.98 mVpp and 56.97 ± 7.53 mVpp, respectively. The IB coefficient was −89.39 ± 2.44 dB for K562 cells and −89.00 ± 1.19 dB for RBCs. The spectral slope and intercept were 0.30 ± 0.19 dB/MHz and −56.07 ± 17.17 dB, respectively, for K562 cells and 0.78 ± 0.092 dB/MHz and −98.18 ± 8.80 dB, respectively, for RBCs. Midband fits of K562 cells and RBCs were −31.02 ± 3.04 dB and −33.51 ± 1.55 dB, respectively. Acoustic cellular discrimination via these parameters was tested by Student’s t-test. Their values, except for the IB value, showed statistically significant difference (p < 0.001). This paper reports for the first time that ultrasonic scattering measurements can be made on a live single cell with a highly focused high-frequency ultrasound microbeam at 86 MHz. These results also suggest the feasibility of ultrasonic scattering as a sensing mechanism in