Science.gov

Sample records for receivers back-end modules

  1. VLBI2010 Receiver Back End Comparison

    NASA Technical Reports Server (NTRS)

    Petrachenko, Bill

    2013-01-01

    VLBI2010 requires a receiver back-end to convert analog RF signals from the receiver front end into channelized digital data streams to be recorded or transmitted electronically. The back end functions are typically performed in two steps: conversion of analog RF inputs into IF bands (see Table 2), and conversion of IF bands into channelized digital data streams (see Tables 1a, 1b and 1c). The latter IF systems are now completely digital and generically referred to as digital back ends (DBEs). In Table 2 two RF conversion systems are compared, and in Tables 1a, 1b, and 1c nine DBE systems are compared. Since DBE designs are advancing rapidly, the data in these tables are only guaranteed to be current near the update date of this document.

  2. DBBC - A Flexible Environment for VLBI and Space Research: Digital Receiver and Back-end Systems

    NASA Astrophysics Data System (ADS)

    Tuccari, G.; Buttaccio, S.; Nicotra, G.; Alef, W.; Keller, R.; Nalbach, M.; Wunderlich, M.

    2007-07-01

    The Digital Base Band Converter project produced a general method and a class of boards giving the possibility to build a general purpose radio system for VLBI or single-dish observational activities. Moreover it is evident as disposing of elements able to operate in a frequency range of few gigahertz, the same parts can be adopted for the direct sampling of radio frequency bands, and not only for intermediate frequency stages. Such approach suggests the realization of what can be defined a 'digital radio system', where such definition would include receivers with conversion not realized with analogue techniques, while still maintaining only amplification stages in the analogue domain in order to satisfy requirements for the analogue to digital conversion unit. This paper presents a description of the elements developed in the DBBC project, with their use in different environments, in order to realize different instruments. The flexibility of the system is then evident because an appropriate distribution and assembly of parts is able to satisfy more requirements. The description includes also the upgrade program where new elements with improvements are introduced for additional functionalities and optimization of the general performance.

  3. Cryogenic 160-GHz MMIC Heterodyne Receiver Module

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

    . Additionally, the use of a W-band isolator between the receiver module and the local oscillator source also improved the noise temperature substantially. This may be because the mixer was presented with a better impedance match with the use of the isolator. Cryogenic testing indicates a system noise temperature of 100 K or less at 166 GHz. Prior tests of the MMIC amplifiers alone have resulted in a system noise temperature of 65.70 K in the same frequency range (.160 GHz) when cooled to an ambient temperature of 20 K. While other detector systems may be slightly more sensitive (such as SIS mixers), they require more cooling (to 4 K ambient) and are not as easily scalable to build a large array, due to the need for large magnets and other equipment. When cooled to 20 K, this receiver module achieves approximately 100 K system noise temperature, which is slightly higher than single-amplifier module results obtained at JPL (65.70 K when an amplifier is corrected for back-end noise contributions). If this performance can be realized in practice, and a scalable array can be produced, the impact on cosmic microwave background experiments, astronomical and Earth spectroscopy, interferometry, and radio astronomy in general will be dramatic.

  4. Compact, Miniature MMIC Receiver Modules for an MMIC Array Spectrograph

    NASA Technical Reports Server (NTRS)

    Kangaslahti, Pekka P.; Gaier, Todd C.; Cooperrider, Joelle T.; Samoska, Lorene A.; Soria, Mary M.; ODwyer, Ian J.; Weinreb, Sander; Custodero, Brian; Owen, Heahter; Grainge, Keith; Church, Sarah; Lai, Richard; Mei, Xiaobing

    2009-01-01

    A single-pixel prototype of a W-band detector module with a digital back-end was developed to serve as a building block for large focal-plane arrays of monolithic millimeter-wave integrated circuit (MMIC) detectors. The module uses low-noise amplifiers, diode-based mixers, and a WR10 waveguide input with a coaxial local oscillator. State-of-the-art InP HEMT (high electron mobility transistor) MMIC amplifiers at the front end provide approximately 40 dB of gain. The measured noise temperature of the module, at an ambient temperature of 300 K, was found to be as low as 450 K at 95 GHz. The modules will be used to develop multiple instruments for astrophysics radio telescopes, both on the ground and in space. The prototype is being used by Stanford University to characterize noise performance at cryogenic temperatures. The goal is to achieve a 30-50 K noise temperature around 90 GHz when cooled to a 20 K ambient temperature. Further developments include characterization of the IF in-phase (I) and quadrature (Q) signals as a function of frequency to check amplitude and phase; replacing the InP low-noise amplifiers with state-of-the-art 35-nm-gate-length NGC low-noise amplifiers; interfacing the front-end module with a digital back-end spectrometer; and developing a scheme for local oscillator and IF distribution in a future array. While this MMIC is being developed for use in radio astronomy, it has the potential for use in other industries. Applications include automotive radar (both transmitters and receivers), communication links, radar systems for collision avoidance, production monitors, ground-penetrating sensors, and wireless personal networks.

  5. A Back-End Data Management Experiment.

    DTIC Science & Technology

    1981-09-01

    TyoNalShpResearch ,. AREA & WORK UNIT NUMBERSDavi Tayor Nval hipProgram Element 62760$ and Development Center L, _i’.A TF3309 Bethesda, Maryland 20084 Wr nt~33o...communications costs Level one, with editor and syntax checker, appears to offer the best overall solu- tion. It is minimum level at which all data and structure...dramatically reduced. The problem will be approached from both ends: host and back-end. Table 9 shows that, for the best case (lowest elapsed time/DML

  6. Back end of an enduring fuel cycle

    SciTech Connect

    Pillay, K.K.S.

    1998-03-01

    An enduring nuclear fuel cycle is an essential part of sustainable consumption, the process whereby world`s riches are consumed in a responsible manner so that future generations can continue to enjoy at least some of them. In many countries, the goal of sustainable development has focused attention on the benefits of nuclear technologies. However, sustenance of the nuclear fuel cycle is dependent on sensible management of all the resources of the fuel cycle, including energy, spent fuels, and all of its side streams. The nuclear fuel cycle for energy production has suffered many traumas since the mid seventies. The common basis of technologies producing nuclear explosives and consumable nuclear energy has been a preoccupation for some, predicament for others, and a perception problem for many. It is essential to reestablish a reliable back end of the nuclear fuel cycle that can sustain the resource requirements of an enduring full cycle. This paper identifies some pragmatic steps necessary to reverse the trend and to maintain a necessary fuel cycle option for the future.

  7. A 30 GHz monolithic receive module

    NASA Technical Reports Server (NTRS)

    Mondal, J.; Contolatis, T.; Geddes, J.; Bauhahn, P.; Sokolov, V.

    1990-01-01

    The technical achievements and deliveries made during the duration of the program to develop a 30 GHz monolithic receive module for communication feed array applications and to deliver submodules and 30 GHz monolithic receive modules for experimental evaluation are discussed. Key requirements include an overall receive module noise figure of 5 dB, a 30 dB RF-to-RF gain with six levels of intermediate gain control, a five bit phase shifter, and a maximum power consumption of 250 mW. In addition, the monolithic receive module design addresses a cost goal of less than one thousand dollars (1980 dollars) per module in unit buys of 5,000 or more, and a mechanical configuration that is applicable to a spaceborne phase array system. An additional task for the development and delivery of 32 GHz phase shifter integrated circuit (IC) for deep space communication is also described.

  8. 40 CFR 63.493 - Back-end process provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins § 63.493 Back-end process... residual organic HAP limitations. Compliance with these residual organic HAP limitations may be achieved...

  9. The 30-GHz monolithic receive module

    NASA Technical Reports Server (NTRS)

    Bauhahn, P.; Geddes, J.; Sokolov, V.; Contolatis, T.

    1988-01-01

    The fourth year progress is described on a program to develop a 27.5 to 30 GHz GaAs monolithic receive module for spaceborne-communication antenna feed array applications, and to deliver submodules for experimental evaluation. Program goals include an overall receive module noise figure of 5 dB, a 30 dB RF to IF gain with six levels of intermediate gain control, a five bit phase shifter, and a maximum power consumption of 250 mW. Submicron gate length single and dual gate FETs are described and applied in the development of monolithic gain control amplifiers and low noise amplifiers. A two-stage monolithic gain control amplifier based on ion implanted dual gate MESFETs was designed and fabricated. The gain control amplifier has a gain of 12 dB at 29 GHz with a gain control range of over 13 dB. A two-stage monolithic low noise amplifier based on ion implanted MESFETs which provides 7 dB gain with 6.2 dB noise figure at 29 GHz was also developed. An interconnected receive module containing LNA, gain control, and phase shifter submodules was built using the LNA and gain control ICs as well as a monolithic phase shifter developed previously under this program. The design, fabrication, and evaluation of this interconnected receiver is presented. Progress in the development of an RF/IF submodule containing a unique ion implanted diode mixer diode and a broadband balanced mixer monolithic IC with on-chip IF amplifier and the initial design of circuits for the RF portion of a two submodule receiver are also discussed.

  10. The 30-GHz monolithic receive module

    NASA Technical Reports Server (NTRS)

    Sokolov, V.; Geddes, J.; Bauhahn, P.

    1983-01-01

    Key requirements for a 30 GHz GaAs monolithic receive module for spaceborne communication antenna feed array applications include an overall receive module noise figure of 5 dB, a 30 dB RF to IF gain with six levels of intermediate gain control, a five-bit phase shifter, and a maximum power consumption of 250 mW. The RF designs for each of the four submodules (low noise amplifier, some gain control, phase shifter, and RF to IF sub-module) are presented. Except for the phase shifter, high frequency, low noise FETs with sub-half micron gate lengths are employed in the submodules. For the gain control, a two stage dual gate FET amplifier is used. The phase shifter is of the passive switched line type and consists of 5-bits. It uses relatively large gate width FETs (with zero drain to source bias) as the switching elements. A 20 GHz local oscillator buffer amplifier, a FET compatible balanced mixer, and a 5-8 GHz IF amplifier constitute the RF/IF sub-module. Phase shifter fabrication using ion implantation and a self-aligned gate technique is described. Preliminary RF results obtained on such phase shifters are included.

  11. Synchronization tracking in pulse position modulation receiver

    NASA Technical Reports Server (NTRS)

    Vilnrotter, Victor A.

    1987-01-01

    A clock pulse generator for decoding pulse position modulation in an optical communication receiver is synchronized by a delay tracking loop which multiplies impulses of a data pulse by the square wave clock pulses from the generator to produce positive impulses when the clock pulse is of one level, and negative impulses when the clock pulse is of another level. A delay tracking loop integrates the impulses and produces an error signal that adjusts the delay so the clock pulses will be synchronized with data pulses. A dead-time tau sub d is provided between data pulses of an interval tau sub p in the data pulse period tau. When synchronized, the average number of positive impulses integrated will equal the average number of negative impulses over the continuous stream of data pulses.

  12. Back end valves: history and modifications, status report, June 1983

    SciTech Connect

    Not Available

    1984-02-01

    At the Grimethorpe Experimental Facility the valves which control the combustor freeboard pressure are known as the back end valves. They are situated downstream of the main heat exchanger. They are required to work under adverse conditions and their operation has not been without problems. The report provides a description of the valves and a history of their operation and modifications from December 1980 to April 1983. Considerable erosion and control problems were experienced during 1981, however, operational and mechanical modifications have now been made which have greatly improved the reliability of the valves.

  13. Receivers and Transmitters. Electronics Module 6. Instructor's Guide.

    ERIC Educational Resources Information Center

    Everett, Jim

    This module is the sixth of 10 modules in the competency-based electronics series. Introductory materials include a listing of competencies addressed in the module and a cross-reference table of instructional materials. Two instructional units cover: (1) AM/FM transmitter and receiver basics; and (2) satellite systems, antennas, and analyzers.…

  14. Interference-Detection Module in a Digital Radar Receiver

    NASA Technical Reports Server (NTRS)

    Fischman, Mark; Berkun, Andrew; Chu, Anhua; Freedman, Adam; Jourdan, Michael; McWatters, Dalia; Paller, Mimi

    2009-01-01

    A digital receiver in a 1.26-GHz spaceborne radar scatterometer now undergoing development includes a module for detecting radio-frequency interference (RFI) that could contaminate scientific data intended to be acquired by the scatterometer. The role of the RFI-detection module is to identify time intervals during which the received signal is likely to be contaminated by RFI and thereby to enable exclusion, from further scientific data processing, of signal data acquired during those intervals. The underlying concepts of detection of RFI and rejection of RFI-contaminated signal data are also potentially applicable in advanced terrestrial radio receivers, including software-defined radio receivers in general, receivers in cellular telephones and other wireless consumer electronic devices, and receivers in automotive collision-avoidance radar systems.

  15. Modified timing module for Loran-C receiver

    NASA Technical Reports Server (NTRS)

    Lilley, R. W.

    1983-01-01

    Full hardware documentation is provided for the circuit card implementing the Loran-C timing loop, and the receiver event-mark and re-track functions. This documentation is to be combined with overall receiver drawings to form the as-built record for this device. Computer software to support this module is integrated with the remainder of the receiver software, in the LORPROM program.

  16. Evaluation tests for photovoltaic concentrator receiver sections and modules

    SciTech Connect

    Woodworth, J.R.; Whipple, M.L.

    1992-06-01

    Sandia has developed a third-generation set of specifications for performance and reliability testing of photovoltaic concentrator modules. Several new requirements have been defined. The primary purpose of the tests is to screen new concentrator designs and new production runs for susceptibility to known failure mechanisms. Ultraviolet radiation testing of materials precedes receiver section and module performance and environmental tests. The specifications include the purpose, procedure, and requirements for each test. Recommendations for future improvements are presented.

  17. Application and analysis of rake receiver to hybrid CPM modulation

    NASA Astrophysics Data System (ADS)

    Norris, James A.; Nieto, John W.

    2011-06-01

    Constant Envelope, Spread Spectrum Modulation is highly desirable for low-power, battery-operated systems. It has been demonstrated that Hybrid CPM is a constant envelope modulation with similar frequency diversity properties to the standard spread-spectrum m-PSK DSSS and spread-MSK modulation schemes while retaining a superior emissions profile. This paper continues the analysis of the novel constant envelope spread spectrum modulation technique with an analysis of the commonly utilized rake receiver signal processing. Initially, a simple channel model is developed to illustrate and compare the convergence of the channel estimate over a fixed, non-time-varying channel. A more complex, wireless channel model is then developed and a new corresponding method for channel estimation created. A Monte- Carlo simulated bit error rate performance of Hybrid CPM is then generated to evaluate the overall performance of the Hybrid CPM modulation scheme.

  18. 40 CFR 63.499 - Back-end process provisions-reporting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Compliance Status specified in § 63.506(e)(5). (1) The type of elastomer product processed in the back-end... reporting period divided by the total mass of elastomer produced during the corresponding 12-month...

  19. 40 CFR 63.499 - Back-end process provisions-reporting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Compliance Status specified in § 63.506(e)(5). (1) The type of elastomer product processed in the back-end... reporting period divided by the total mass of elastomer produced during the corresponding 12-month...

  20. 40 CFR 63.499 - Back-end process provisions-reporting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Compliance Status specified in § 63.506(e)(5). (1) The type of elastomer product processed in the back-end... reporting period divided by the total mass of elastomer produced during the corresponding 12-month...

  1. A 30 GHz monolithic receive module technology assessment

    NASA Technical Reports Server (NTRS)

    Geddes, J.; Sokolov, V.; Bauhahn, P.; Contolatis, T.

    1988-01-01

    This report is a technology assessment relevant to the 30 GHz Monolithic Receive Module development. It is based on results obtained on the present NASA Contract (NAS3-23356) as well as on information gathered from literature and other industry sources. To date the on-going Honeywell program has concentrated on demonstrating the so-called interconnected receive module which consists of four monolithic chips - the low noise front-end amplifier (LNA), the five bit phase shifter (PS), the gain control amplifier (GC), and the RF to IF downconverter (RF/IF). Results on all four individual chips have been obtained and interconnection of the first three functions has been accomplished. Future work on this contract is aimed at a higher level of integration, i.e., integration of the first three functions (LNA + PS + GC) on a single GaAs chip. The report presents the status of this technology and projections of its future directions.

  2. Design of Optical Pulse Position Modulation (PPM) Translating Receiver

    SciTech Connect

    Mendez, A J; Hernandez, V J; Gagliardi, R M; Bennett, C V

    2009-06-19

    M-ary pulse position modulation (M-ary PPM) signaling is a means of transmitting multiple bits per symbol in an intensity modulated/direct detection (IM/DD) system. PPM is used in applications with average power limitations. In optical communication systems, PPM becomes challenging to implement at gigabit rates and/or large M, since pulsed signaling requires higher electronic processing bandwidths than the fundamental transmission rate. they have thus been exploring techniques for PPM communications using optical processing. Previous work described a transmitter algorithm that directly translates a bit sequence of N digital bits to the optical pulse position m for any M = 2{sup N}. It has been considerably more difficult to define a similar receiver algorithm that translates the received optical pulse position directly back to a bit sequence with minimal electronic processing. Designs for specific Ms (e.g., 4-ary) have been shown and implemented, but are difficult to scale to larger M. In this work, they present for the first time a generalized PPM translating receiver that is applicable to all M and data rates.

  3. A 150 GHz Receiver Module for Astronomical Observations

    NASA Astrophysics Data System (ADS)

    Voll, Patricia; Lau, J.; Sieth, M.; Church, S.; Samoska, L. A.; Kangaslahti, P. P.; Soria, M.; Gaier, T. C.; Van Winkle, D.; Tantawi, S.

    2011-01-01

    A compact, wide-band, heterodyne amplifier module has been designed to operate in the 150 GHz atmospheric window using High Electron Mobility Transistor (HEMT) amplifier technology. This frequency range is important for many astrophysical science applications, including spectral line studies, separating the cosmic microwave background (CMB) radiation from foregrounds, and detecting the hot gas around galaxy clusters using the Sunyaev-Zeldovich effect. HEMT-based receiver arrays with excellent noise and scalability are already being manufactured around 100 GHz, but recent advances have made it possible to extend this technology to even higher frequencies. The prototype 150 GHz module housing utilizes Monolithic Millimeter-Wave Integrated Circuit (MMIC) InP Low Noise Amplifiers (LNAs). These amplifiers, along with a second harmonic mixer, bias circuitry, and connectors, are contained in a single, split-block housing approximately one inch cubed in size. Preliminary cryogenic tests have measured a system noise temperature of 150 K over a bandwidth of 25 GHz with a minimum noise temperature of less than 100 K at 168 GHz. The minimum noise temperature is less than 100 K at 168 GHz. Module improvements for the second phase are expected to reduce the noise temperature to the minimum allowed by the device limit. Development of a 4-element array to demonstrate the scalability of these receivers is currently underway, and will serve as a prototype for much larger, 100-element arrays for astrophysical applications. In the future, a space mission incorporating an array of these modules could be used to detect the curl modes (B-modes) of the CMB polarization, which is important for the search for the signature of inflation.

  4. 40 CFR 63.498 - Back-end process provisions-recordkeeping.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... technology, or by control or recovery devices. (4) If the back-end process operation is subject to an... operation using stripping technology to comply with a residual organic HAP limitation in § 63.494(a)(1... stripping technology to comply with a residual organic HAP limitation in § 63.494(a)(1) through (3),...

  5. 40 CFR 63.498 - Back-end process provisions-recordkeeping.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... technology, or by control or recovery devices. (4) If the back-end process operation is subject to an... operation using stripping technology to comply with a residual organic HAP limitation in § 63.494(a)(1... stripping technology to comply with a residual organic HAP limitation in § 63.494(a)(1) through (3),...

  6. 40 CFR 63.498 - Back-end process provisions-recordkeeping.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... technology, or by control or recovery devices. (4) If the back-end process operation is subject to an... operation using stripping technology to comply with a residual organic HAP limitation in § 63.494(a)(1... stripping technology to comply with a residual organic HAP limitation in § 63.494(a)(1) through (3),...

  7. Source-Constrained Recall: Front-End and Back-End Control of Retrieval Quality

    ERIC Educational Resources Information Center

    Halamish, Vered; Goldsmith, Morris; Jacoby, Larry L.

    2012-01-01

    Research on the strategic regulation of memory accuracy has focused primarily on monitoring and control processes used to edit out incorrect information after it is retrieved (back-end control). Recent studies, however, suggest that rememberers also enhance accuracy by preventing the retrieval of incorrect information in the first place (front-end…

  8. 40 CFR 63.498 - Back-end process provisions-recordkeeping.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... (1) The type of elastomer product processed in the back-end operation. (2) The type of process...). These records shall include the following for each sample: (i) Elastomer type, (ii) The date and time the sample was collected, (iii) The corresponding quantity of elastomer processed over the time...

  9. 40 CFR 63.494 - Back-end process provisions-residual organic HAP limitations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... organic HAP limitations. 63.494 Section 63.494 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES National Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins § 63.494 Back-end process provisions—residual organic HAP limitations. (a) The monthly weighted...

  10. 40 CFR 63.495 - Back-end process provisions-procedures to determine compliance using stripping technology.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: Group I Polymers and Resins § 63.495 Back-end process provisions—procedures to determine compliance using stripping technology. (a) If an owner or operator complies with the residual organic HAP... residual organic HAP content for each month in which any portion of the back-end of an elastomer...

  11. 40 CFR Table 8 to Subpart U of... - Summary of Compliance Alternative Requirements for the Back-End Process Provisions

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Requirements for the Back-End Process Provisions 8 Table 8 to Subpart U of Part 63 Protection of Environment... Compliance Alternative Requirements for the Back-End Process Provisions Compliance alternative Parameter to... Sampling Residual organic HAP content in each sample of crumb or latex (1) If a stripper operated in...

  12. 40 CFR Table 8 to Subpart U of... - Summary of Compliance Alternative Requirements for the Back-End Process Provisions

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Requirements for the Back-End Process Provisions 8 Table 8 to Subpart U of Part 63 Protection of Environment... Compliance Alternative Requirements for the Back-End Process Provisions Compliance alternative Parameter to... Sampling Residual organic HAP content in each sample of crumb or latex (1) If a stripper operated in...

  13. Back-end algorithms that enhance the functionality of a biomimetic acoustic gunfire direction finding system

    NASA Astrophysics Data System (ADS)

    Pu, Yirong; Kelsall, Sarah; Ziph-Schatzberg, Leah; Hubbard, Allyn

    2009-05-01

    Increasing battlefield awareness can improve both the effectiveness and timeliness of response in hostile military situations. A system that processes acoustic data is proposed to handle a variety of possible applications. The front-end of the existing biomimetic acoustic direction finding system, a mammalian peripheral auditory system model, provides the back-end system with what amounts to spike trains. The back-end system consists of individual algorithms tailored to extract specific information. The back-end algorithms are transportable to FPGA platforms and other general-purpose computers. The algorithms can be modified for use with both fixed and mobile, existing sensor platforms. Currently, gunfire classification and localization algorithms based on both neural networks and pitch are being developed and tested. The neural network model is trained under supervised learning to differentiate and trace various gunfire acoustic signatures and reduce the effect of different frequency responses of microphones on different hardware platforms. The model is being tested against impact and launch acoustic signals of various mortars, supersonic and muzzle-blast of rifle shots, and other weapons. It outperforms the cross-correlation algorithm with regard to computational efficiency, memory requirements, and noise robustness. The spike-based pitch model uses the times between successive spike events to calculate the periodicity of the signal. Differences in the periodicity signatures and comparisons of the overall spike activity are used to classify mortar size and event type. The localization of the gunfire acoustic signals is further computed based on the classification result and the location of microphones and other parameters of the existing hardware platform implementation.

  14. [One case of papillary adenocarcinoma located in the back-end of nasal septum].

    PubMed

    Zang, Jian; Liu, Qian; Jiang, Xuejun

    2015-02-01

    Patients with nasopharyngeal foreign body sensation for 3 years, and had nasal obstruction in the past six months. electric nasopharyngoscopy: a irregular ellipse shape mass occupied in the nasopharynx, the mass surface is not smooth, with erosion ulcer and filthy secretions, the mass had a root in the back-end of nasal septum, and was adjacent to the bilateral round pillow. Sinus CT showed an irregular soft tissue shadow connected to the nasal septum backend in the nasopharynx, the size is about 2.8 cm X 3.5 cm, CT value is about 43 HU. Pathological examination: papillary adenocarcinoma.

  15. Modified timing module for Loran-C receiver

    NASA Technical Reports Server (NTRS)

    Lilley, Robert W.

    1987-01-01

    Hardware documentation is provided for the modified Loran-C timing module, which used interrupt-driven software control in determing loop sample times. Computer loading is reduced by eliminating polled operation of the timing loop.

  16. Processor-controlled timing module for LORAN-C receiver

    NASA Technical Reports Server (NTRS)

    Lilley, R. W.

    1984-01-01

    Hardware documentation is provided for the modified LORAN-C timing module, which uses direct software control in determining loop sample times. Computer loading is reduced by eliminating polled operation of the timing loop.

  17. Processor-controlled timing module for Loran-C receiver

    NASA Technical Reports Server (NTRS)

    Lilley, Robert W.

    1987-01-01

    Hardware documentation is provided for the modified Loran-C timing module, which uses direct software control in determining loop sample times. Computer loading is reduced by eliminating polled operation of the timing loop.

  18. Modified timing module for Loran-C receiver

    NASA Technical Reports Server (NTRS)

    Lilley, R. W.

    1983-01-01

    Hardware documentation is provided for the modified LORAN-C timing module, which uses interrupt-driven software control in determining loop sample times. Computer loading is reduced by eliminating polled operation of the timing loop.

  19. Waste Receiving and Processing (WRAP) Module 1 Hazards Assessment

    SciTech Connect

    CAMPBELL, L.R.

    1999-09-29

    This document establishes the technical basis in support of Emergency Planning activities for the WRAP Module 1 Facility on the Hanford Site. Through this document, the technical basis for the development of facility specific Emergency Action Levels and Emergency Planning Zone is demonstrated.

  20. The crucial importance of the back-end in multinational initiatives to enhance fuel cycle security

    SciTech Connect

    McCombie, Charles; Chapman, Neil; Isaacs, Thomas H.

    2007-07-01

    There have been repeated proposals for establishing multinational cooperation approaches that could reduce the security concerns of spreading nuclear technologies. Most recently, there have been initiatives by both Russia (GNPI ) and the USA (GNEP) - each aimed at promoting nuclear power whilst limiting security concerns. In practice, both initiatives place emphasis on the supply of reactors and enriched fuel but neither has made clear and specific proposals about the back-end part of the arrangement. The primary incentive offered to the user countries is 'security of supply' of the front end services. However, there is no current shortage of supply of front end services, so that the incentives are not large. A much greater incentive could be the provision of a spent fuel or waste disposal service. The fuel supplied to Tier 2 countries could be shipped back (with no return of wastes) to the supplier or else to an accepted third party country that is trusted to operate safe and secure disposal facilities. If a comprehensive service that obviates the need for a national deep repository is offered to small countries then there will be a really strong incentive for them to sign up to GNEP or GNPI type deals. (authors)

  1. An open-source data storage and visualization back end for experimental data.

    PubMed

    Nielsen, Kenneth; Andersen, Thomas; Jensen, Robert; Nielsen, Jane H; Chorkendorff, Ib

    2014-04-01

    In this article, a flexible free and open-source software system for data logging and presentation will be described. The system is highly modular and adaptable and can be used in any laboratory in which continuous and/or ad hoc measurements require centralized storage. A presentation component for the data back end has furthermore been written that enables live visualization of data on any device capable of displaying Web pages. The system consists of three parts: data-logging clients, a data server, and a data presentation Web site. The logging of data from independent clients leads to high resilience to equipment failure, whereas the central storage of data dramatically eases backup and data exchange. The visualization front end allows direct monitoring of acquired data to see live progress of long-duration experiments. This enables the user to alter experimental conditions based on these data and to interfere with the experiment if needed. The data stored consist both of specific measurements and of continuously logged system parameters. The latter is crucial to a variety of automation and surveillance features, and three cases of such features are described: monitoring system health, getting status of long-duration experiments, and implementation of instant alarms in the event of failure.

  2. A digital receiver module with direct data acquisition for magnetic resonance imaging systems.

    PubMed

    Tang, Weinan; Sun, Hongyu; Wang, Weimin

    2012-10-01

    A digital receiver module for magnetic resonance imaging (MRI) with detailed hardware implementations is presented. The module is based on a direct sampling scheme using the latest mixed-signal circuit design techniques. A single field-programmable gate array chip is employed to perform software-based digital down conversion for radio frequency signals. The modular architecture of the receiver allows multiple acquisition channels to be implemented on a highly integrated printed circuit board. To maintain the phase coherence of the receiver and the exciter in the context of direct sampling, an effective phase synchronization method was proposed to achieve a phase deviation as small as 0.09°. The performance of the described receiver module was verified in the experiments for both low- and high-field (0.5 T and 1.5 T) MRI scanners and was compared to a modern commercial MRI receiver system.

  3. 40 CFR Table 8 to Subpart U of... - Summary of Compliance Alternative Requirements for the Back-End Process Provisions

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Requirements for the Back-End Process Provisions 8 Table 8 to Subpart U of Part 63 Protection of Environment...: Group I Polymers and Resins Pt. 63, Subpt. U, Table 8 Table 8 to Subpart U of Part 63—Summary of... be monitored Requirements Compliance Using Stripping Technology, Demonstrated through...

  4. 40 CFR Table 8 to Subpart U of... - Summary of Compliance Alternative Requirements for the Back-End Process Provisions

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Requirements for the Back-End Process Provisions 8 Table 8 to Subpart U of Part 63 Protection of Environment...: Group I Polymers and Resins Pt. 63, Subpt. U, Table 8 Table 8 to Subpart U of Part 63—Summary of... be monitored Requirements Compliance Using Stripping Technology, Demonstrated through...

  5. 40 CFR 63.497 - Back-end process provisions-monitoring provisions for control and recovery devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Polymers and Resins § 63.497 Back-end process provisions—monitoring provisions for control and recovery devices. (a) An owner or operator complying with the residual organic HAP limitations in § 63.494(a) using... Notification of Compliance Status or the operating permit application, as required in § 63.506(e)(5) or...

  6. 40 CFR 63.496 - Back-end process provisions-procedures to determine compliance using control or recovery devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Pollutant Emissions: Group I Polymers and Resins § 63.496 Back-end process provisions—procedures to... residual organic HAP limitations in § 63.494(a) using control or recovery devices, compliance shall be... conducted when the grade of elastomer product with the highest residual organic HAP content leaving...

  7. 40 CFR 63.494 - Back-end process provisions-residual organic HAP and emission limitations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... organic HAP and emission limitations. 63.494 Section 63.494 Protection of Environment ENVIRONMENTAL... Polymers and Resins § 63.494 Back-end process provisions—residual organic HAP and emission limitations. (a) The monthly weighted average residual organic HAP content of all grades of styrene butadiene...

  8. 40 CFR 63.494 - Back-end process provisions-residual organic HAP and emission limitations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... organic HAP and emission limitations. 63.494 Section 63.494 Protection of Environment ENVIRONMENTAL... Polymers and Resins § 63.494 Back-end process provisions—residual organic HAP and emission limitations. (a) The monthly weighted average residual organic HAP content of all grades of styrene butadiene...

  9. AREVA Back-End Possibilities for the Used Fuel of Research Test Reactors

    SciTech Connect

    Auziere, P.; Emin, J.L.; Louvet, T.; Ohayon, D.; Hunter, I.

    2006-07-01

    One of the major issues faced by the Research and Test Reactor (RTR) operators is the back end management of the used fuel elements. RTR used fuel for both HEU and LEU types are problematic for storing and disposal as their Aluminium cladding degrades leading to activity release, possible loss of containment and criticality concerns. Thus, direct disposal of RTR used fuel, (without prior treatment and conditioning) is in this respect hardly suitable. In the same manner, long term interim storage of RTR used fuel has to take into account the issue of fuel corrosion. Treating RTR used fuel allows separating the content into recyclable materials and residues. It offers many advantages as compared to direct disposal such as the retrieval of valuable fissile material, the reduction of radio-toxicity and a very significant reduction of the volume of the ultimate waste package (reduction factor between 30 and 50). In addition, the vitrification of the residues provides a package that has been specifically designed to ensure long term durability for long term interim storage as well as final disposal (99% of the activity is encapsulated into a stable matrix). RTR fuel treatment process was developed several decades ago by AREVA with now thirty years of experience at an industrial level. The treatment process consists in dissolving the whole assembly (including the Al cladding) in nitric acid and then diluting it with standard Uranium Oxide fuel dissolution liquor prior to treatment with the nominal Tributylphosphate solvent extraction process. A wide range of RTR spent fuel has already been treated in the AREVA facilities. First, at the Marcoule plant over 18 tons of U-Al type RTR fuel from 21 reactors in 11 countries was processed. The treatment activities are now undertaken at the La Hague plant where 17 tons of RTR used fuel from Australia Belgium, and France aligned for treatment. In June 2005, AREVA started to treat at La Hague ANSTO's Australian RTR used fuel from

  10. Quantification of Back-End Nuclear Fuel Cycle Metrics Uncertainties Due to Cross Sections

    SciTech Connect

    Tracy E. Stover, Jr.

    2007-11-01

    This work examines uncertainties in the back end fuel cycle metrics of isotopic composition, decay heat, radioactivity, and radiotoxicity. Most advanced fuel cycle scenarios, including the ones represented in this work, are limited by one or more of these metrics, so that quantification of them becomes of great importance in order to optimize or select one of these scenarios. Uncertainty quantification, in this work, is performed by propagating cross-section covariance data, and later number density covariance data, through a reactor physics and depletion code sequence. Propagation of uncertainty is performed primarily via the Efficient Subspace Method (ESM). ESM decomposes the covariance data into singular pairs and perturbs input data along independent directions of the uncertainty and only for the most significant values of that uncertainty. Results of these perturbations being collected, ESM directly calculates the covariance of the observed output posteriori. By exploiting the rank deficient nature of the uncertainty data, ESM works more efficiently than traditional stochastic sampling, but is shown to produce equivalent results. ESM is beneficial for very detailed models with large amounts of input data that make stochastic sampling impractical. In this study various fuel cycle scenarios are examined. Simplified, representative models of pressurized water reactor (PWR) and boiling water reactor (BWR) fuels composed of both uranium oxide and mixed oxides are examined. These simple models are intended to give a representation of the uncertainty that can be associated with open uranium oxide fuel cycles and closed mixed oxide fuel cycles. The simplified models also serve as a demonstration to show that ESM and stochastic sampling produce equivalent results, because these models require minimum computer resources and have amounts of input data small enough such that either method can be quickly implemented and a numerical experiment performed. The simplified

  11. Fluidised-bed combustion. IEA Grimethorpe Pressurized Fluidised-Bed Test Facility back-end valves: history and modification

    SciTech Connect

    Not Available

    1982-01-01

    The pressure of the combustor freeboard is controlled by one of three back-end pressure control valves. The back-end valves are so called as they are situated at the back end of the exhaust gas system at the outlet of the main exhaust gas heat exchanger. In normal operation one of the valves is on pressure control duty, another on pressure relief duty, and the third is shut and available for operation on control or relief duty. These valves are subjected to a very arduous duty: temperatures of up to 350/sup 0/C to 375/sup 0/C with pressure drops of approximately 8 bar, and an estimated solids content of up to 400 ppM in the exhaust gases. Severe erosion on the valves seats, shafts, seals and upstream and downstream pipework has occurred and a large amount of remedial work has been carried out on the valves and adjacent pipework. This report describes the history of the valve erosion, the maintenance/remedial work carried out, and the steps being taken to attempt to solve the problem for future tests.

  12. Back-end and interface implementation of the STS-XYTER2 prototype ASIC for the CBM experiment

    NASA Astrophysics Data System (ADS)

    Kasinski, K.; Szczygiel, R.; Zabolotny, W.

    2016-11-01

    Each front-end readout ASIC for the High-Energy Physics experiments requires robust and effective hit data streaming and control mechanism. A new STS-XYTER2 full-size prototype chip for the Silicon Tracking System and Muon Chamber detectors in the Compressed Baryonic Matter experiment at Facility for Antiproton and Ion Research (FAIR, Germany) is a 128-channel time and amplitude measuring solution for silicon microstrip and gas detectors. It operates at 250 kHit/s/channel hit rate, each hit producing 27 bits of information (5-bit amplitude, 14-bit timestamp, position and diagnostics data). The chip back-end implements fast front-end channel read-out, timestamp-wise hit sorting, and data streaming via a scalable interface implementing the dedicated protocol (STS-HCTSP) for chip control and hit transfer with data bandwidth from 9.7 MHit/s up to 47 MHit/s. It also includes multiple options for link diagnostics, failure detection, and throttling features. The back-end is designed to operate with the data acquisition architecture based on the CERN GBTx transceivers. This paper presents the details of the back-end and interface design and its implementation in the UMC 180 nm CMOS process.

  13. Electroacoustic Evaluation of Frequency-Modulated Receivers Interfaced with Personal Hearing Aids

    ERIC Educational Resources Information Center

    Schafer, Erin C.; Thibodeau, Linda M.; Whalen, Holly S.; Overson, Gary J.

    2007-01-01

    Purpose: The purpose of this study was to compare the electroacoustic outputs of frequency-modulated (FM) systems coupled to hearing aids. Method: Electroacoustic performance of FM systems coupled to hearing aids was determined for 3 FM receivers: body-worn with neck loop, ear-level nonprogrammable, and ear-level programmable. Systems were…

  14. Project management plan, Waste Receiving and Processing Facility, Module 1, Project W-026

    SciTech Connect

    Starkey, J.G.

    1993-05-01

    The Hanford Waste Receiving and Processing Facility Module 1 Project (WRAP 1) has been established to support the retrieval and final disposal of approximately 400K grams of plutonium and quantities of hazardous components currently stored in drums at the Hanford Site.

  15. Decoupling of excitation and receive coils in pulsed magnetic resonance using sinusoidal magnetic field modulation

    NASA Astrophysics Data System (ADS)

    Tseytlin, Mark; Epel, Boris; Sundramoorthy, Subramanian; Tipikin, Dmitriy; Halpern, Howard J.

    2016-11-01

    In pulsed magnetic resonance, the excitation power is many orders of magnitude larger than that induced by the spin system in the receiving coil or resonator. The receiver must be protected during and immediately after the excitation pulse to allow for the energy stored in the resonator to dissipate to a safe level. The time during which the signal is not detected, the instrumental dead-time, can be shortened by using magnetically decoupled excitation and receive coils. Such coils are oriented, with respect to each other, in a way that minimizes the total magnetic flux produced by one coil in the other. We suggest that magnetically decoupled coils can be isolated to a larger degree by tuning them to separate frequencies. Spins are excited at one frequency, and the echo signal is detected at another. Sinusoidal magnetic field modulation that rapidly changes the Larmor frequency of the spins between the excitation and detection events is used to ensure the resonance conditions for both coils. In this study, the relaxation times of trityl-CD3 were measured in a field-modulated pulsed EPR experiment and compared to results obtained using a standard spin echo method. The excitation and receive coils were tuned to 245 and 256.7 MHz, respectively. Using an available rapid-scan, cross-loop EPR resonator, we demonstrated an isolation improvement of approximately 20-30 dB due to frequency decoupling. Theoretical analysis, numerical simulations, and proof-of-concept experiments demonstrated that substantial excitation-detection decoupling can be achieved. A pulsed L-band system, including a small volume bi-modal resonator equipped with modulation coils, was constructed to demonstrate fivefold dead-time reduction in comparison with the standard EPR experiment. This was achieved by detuning of the excitation and receive coils by 26 MHz and using sinusoidal modulation at 480 kHz.

  16. Waste Receiving and Processing Facility Module 1 Data Management System Software Requirements Specification

    SciTech Connect

    Brann, E.C. II

    1994-09-09

    This document provides the software requirements for Waste Receiving and Processing (WRAP) Module 1 Data Management System (DMS). The DMS is one of the plant computer systems for the new WRAP 1 facility (Project W-026). The DMS will collect, store and report data required to certify the low level waste (LLW) and transuranic (TRU) waste items processed at WRAP 1 as acceptable for shipment, storage, or disposal.

  17. Waste Receiving and Processing Facility Module 1 Data Management System software requirements specification

    SciTech Connect

    Rosnick, C.K.

    1996-04-19

    This document provides the software requirements for Waste Receiving and Processing (WRAP) Module 1 Data Management System (DMS). The DMS is one of the plant computer systems for the new WRAP 1 facility (Project W-0126). The DMS will collect, store and report data required to certify the low level waste (LLW) and transuranic (TRU) waste items processed at WRAP 1 as acceptable for shipment, storage, or disposal.

  18. A parameter estimation algorithm for LFM/BPSK hybrid modulated signal intercepted by Nyquist folding receiver

    NASA Astrophysics Data System (ADS)

    Qiu, Zhaoyang; Wang, Pei; Zhu, Jun; Tang, Bin

    2016-12-01

    Nyquist folding receiver (NYFR) is a novel ultra-wideband receiver architecture which can realize wideband receiving with a small amount of equipment. Linear frequency modulated/binary phase shift keying (LFM/BPSK) hybrid modulated signal is a novel kind of low probability interception signal with wide bandwidth. The NYFR is an effective architecture to intercept the LFM/BPSK signal and the LFM/BPSK signal intercepted by the NYFR will add the local oscillator modulation. A parameter estimation algorithm for the NYFR output signal is proposed. According to the NYFR prior information, the chirp singular value ratio spectrum is proposed to estimate the chirp rate. Then, based on the output self-characteristic, matching component function is designed to estimate Nyquist zone (NZ) index. Finally, matching code and subspace method are employed to estimate the phase change points and code length. Compared with the existing methods, the proposed algorithm has a better performance. It also has no need to construct a multi-channel structure, which means the computational complexity for the NZ index estimation is small. The simulation results demonstrate the efficacy of the proposed algorithm.

  19. A hearing aid on-chip system based on accuracy optimized front- and back-end blocks

    NASA Astrophysics Data System (ADS)

    Fanyang, Li; Hao, Jiang

    2014-03-01

    A hearing aid on-chip system based on accuracy optimized front- and back-end blocks is presented for enhancing the signal processing accuracy of the hearing aid. Compared with the conventional system, the accuracy optimized system is characterized by the dual feedback network and the gain compensation technique used in the front- and back-end blocks, respectively, so as to alleviate the nonlinearity distortion caused by the output swing. By using the technique, the accuracy of the whole hearing aid system can be significantly improved. The prototype chip has been designed with a 0.13 μm standard CMOS process and tested with 1 V supply voltage. The measurement results show that, for driving a 16 Ω loudspeaker with a normalized output level of 300 mVp-p, the total harmonic distortion reached about -60 dB, achieving at least three times reduction compared to the previously reported works. In addition, the typical input referred noise is only about 5 μVrms.

  20. Fully back-end TSV process by Cu electro-less plating for 3D smart sensor systems

    NASA Astrophysics Data System (ADS)

    Santagata, F.; Farriciello, C.; Fiorentino, G.; van Zeijl, H. W.; Silvestri, C.; Zhang, G. Q.; Sarro, P. M.

    2013-05-01

    A fully back-end process for high-aspect ratio through-silicon vias (TSVs) for 3D smart sensor systems is developed. Atomic layer deposition of TiN provides a highly conformal barrier as well as a seed layer for metal plating. Cu electro-less plating on the chemically activated TiN surfaces is applied to uniformly fill the TSVs in a significantly shorter time (2 h for 300 μm deep and 20 μm wide TSVs) than with Cu bottom-up electroplating (>20 h). The process is CMOS compatible and can be performed after the last metalization step, making it a fully back-end process (VIA-last approach). Wafers containing metal interconnections on both sides are in fact used as demonstrator. Four-terminal 3D Kelvin structures are fabricated and characterized. An average resistance value of 650 mΩ is measured for 300 μm deep TSVs with an aspect ratio of 15. The crosstalk between adjacent TSVs is also measured by means of S-parameters characterization on dedicated RF test structures. The closest TSVs (75 μm) show a reciprocal crosstalk of less than -20 dB at 30 GHz.

  1. A linear receiver for visible light communication systems with phase modulated OFDM

    NASA Astrophysics Data System (ADS)

    Xie, Gui-Teng; Yu, Hong-Yi; Zhu, Yi-Jun; Ji, Xin-Sheng

    2016-07-01

    In the orthogonal frequency-division multiplexing (OFDM) systems for visible light communication (VLC), the peak-to-average power ratio (PAPR) of OFDM signals is the primary concern of high-speed data transmission. In order to get low PAPR signals and reduce the influence of nonlinearity of the light-emitting diode (LED), a phase modulated OFDM (PM-OFDM) system is developed and a linear receiver is presented. Unlike the conventional angle detection receiver implemented by arctangent calculator, the linear receiver has lower computation complexity and is immune to the threshold effect. Simulation results indicate that the proposed PM-OFDM obtains significant performance gains over DC-biased optical OFDM (DCO-OFDM) and precoded OFDM.

  2. L-Band Transmit/Receive Module for Phase-Stable Array Antennas

    NASA Technical Reports Server (NTRS)

    Andricos, Constantine; Edelstein, Wendy; Krimskiy, Vladimir

    2008-01-01

    Interferometric synthetic aperture radar (InSAR) has been shown to provide very sensitive measurements of surface deformation and displacement on the order of 1 cm. Future systematic measurements of surface deformation will require this capability over very large areas (300 km) from space. To achieve these required accuracies, these spaceborne sensors must exhibit low temporal decorrelation and be temporally stable systems. An L-band (24-cmwavelength) InSAR instrument using an electronically steerable radar antenna is suited to meet these needs. In order to achieve the 1-cm displacement accuracy, the phased array antenna requires phase-stable transmit/receive (T/R) modules. The T/R module operates at L-band (1.24 GHz) and has less than 1- deg absolute phase stability and less than 0.1-dB absolute amplitude stability over temperature. The T/R module is also high power (30 W) and power efficient (60-percent overall efficiency). The design is currently implemented using discrete components and surface mount technology. The basic T/R module architecture is augmented with a calibration loop to compensate for temperature variations, component variations, and path loss variations as a function of beam settings. The calibration circuit consists of an amplitude and phase detector, and other control circuitry, to compare the measured gain and phase to a reference signal and uses this signal to control a precision analog phase shifter and analog attenuator. An architecture was developed to allow for the module to be bidirectional, to operate in both transmit and receive mode. The architecture also includes a power detector used to maintain a transmitter power output constant within 0.1 dB. The use of a simple, stable, low-cost, and high-accuracy gain and phase detector made by Analog Devices (AD8302), combined with a very-high efficiency T/R module, is novel. While a self-calibrating T/R module capability has been sought for years, a practical and cost-effective solution has

  3. The Back End of the Fuel Cycle Moves Front and Center

    SciTech Connect

    Isaacs, T; Choi, J

    2006-02-16

    assurance that it will receive all the fresh fuel it needs for the lifetime of its nuclear power plants, there should be no reason for it to pursue the difficult and costly capability to enrich the fuel itself or to reprocess its spent fuel to recover the produced plutonium for recycle as a fuel in its reactors. However, such offers are unlikely to be fully persuasive if they are not connected to complementary offers for management of the spent nuclear fuel that is created during power production. In this paper, we discuss the complexity of the linkage to spent fuel take-back and the challenges and opportunities this present to nations repository programs.

  4. Polymer planar lightwave circuit based hybrid-integrated coherent receiver for advanced modulation signals

    NASA Astrophysics Data System (ADS)

    Wang, Jin; Han, Yang; Liang, Zhongcheng; Chen, Yongjin

    2012-11-01

    Applying coherent detection technique to advanced modulation formats makes it possible to electronically compensate the signal impairments. A key issue for a successful deployment of coherent detection technique is the availability of cost-efficient and compact integrated receivers, which are composed of an optical 90° hybrid mixer and four photodiodes (PDs). In this work, three different types of optical hybrids are fabricated with polymer planar lightwave circuit (PLC), and hybridly integrated with four vertical backside illuminated III-V PDs. Their performances, such as the insertion loss, the transmission imbalance, the polarization dependence and the phase deviation of 90° hybrid will be discussed.

  5. Receiver development for a solar dynamic power module with respect to space and terrestrial applications

    NASA Astrophysics Data System (ADS)

    Laing, Doerte; Krause, Siegfried; Noyes, Gerold

    1990-10-01

    A heat-pipe/heat-storage receiver concept for solar dynamic energy conversion units with a Stirling engine for space stations is presented. Theoretical estimates for the heat flows between heat pipe, heat storage, and Stirling heater head are described. The heat transfer from and to the storage elements is adequate in all operation modes and states of loading of the storage. The dish/Stirling technology has also a high terrestrial potential. Therefore, to gain experience, a first heat pipe receiver was built for a terrestrial module, using an SPS V-160 Stirling engine. Test results of the performance tests of the V-160 Stirling heated by a natural gas burner and the heat pipe receiver/Stirling unit, heated by an electrical graphite heater, are presented. The V-160 Stirling showed a good part-load performance and a maximum thermal-to-electric conversion efficiency of 26.5 percent at 8.9 kWc power output. The heat pipe receiver performed without problems. A maximum electrical heating power of 35 kW has been applied. Dynamic system behavior has been tested with rapid changes in power input between 0 and 20 kW.

  6. Digital Intermediate Frequency Receiver Module For Use In Airborne Sar Applications

    DOEpatents

    Tise, Bertice L.; Dubbert, Dale F.

    2005-03-08

    A digital IF receiver (DRX) module directly compatible with advanced radar systems such as synthetic aperture radar (SAR) systems. The DRX can combine a 1 G-Sample/sec 8-bit ADC with high-speed digital signal processor, such as high gate-count FPGA technology or ASICs to realize a wideband IF receiver. DSP operations implemented in the DRX can include quadrature demodulation and multi-rate, variable-bandwidth IF filtering. Pulse-to-pulse (Doppler domain) filtering can also be implemented in the form of a presummer (accumulator) and an azimuth prefilter. An out of band noise source can be employed to provide a dither signal to the ADC, and later be removed by digital signal processing. Both the range and Doppler domain filtering operations can be implemented using a unique pane architecture which allows on-the-fly selection of the filter decimation factor, and hence, the filter bandwidth. The DRX module can include a standard VME-64 interface for control, status, and programming. An interface can provide phase history data to the real-time image formation processors. A third front-panel data port (FPDP) interface can send wide bandwidth, raw phase histories to a real-time phase history recorder for ground processing.

  7. Comparison of IPDA lidar receiver sensitivity for coherent detection and for direct detection using sine-wave and pulsed modulation.

    PubMed

    Sun, Xiaoli; Abshire, James B

    2012-09-10

    We use theoretical models to compare the receiver signal to noise ratio (SNR) vs. average rate of detected signal photons for an integrated path differential absorption (IPDA) lidar using coherent detection with continuous wave (CW) lasers and direct detection with sine-wave and pulse modulations. The results show the coherent IPDA lidar has high receiver gain and narrow bandwidth to overcome the effects of detector circuit noise and background light, but the actual receiver performance can be limited by the coherent mixing efficiency, speckle and other factors. For direct detection, using sine-wave modulation allows the use of a low peak power laser transmitter and synchronous detection. The pulse modulation technique requires higher laser peak powers but is more efficient than sine-wave modulation in terms of average detected signal photon rate required to achieve a given receiver SNR. We also conducted experiments for the direct detection cases and the results agreed well with theory.

  8. Waste Receiving and Processing Facility Module 2A: Advanced Conceptual Design Report. Volume 1

    SciTech Connect

    Not Available

    1994-03-01

    This ACDR was performed following completed of the Conceptual Design Report in July 1992; the work encompassed August 1992 to January 1994. Mission of the WRAP Module 2A facility is to receive, process, package, certify, and ship for permanent burial at the Hanford site disposal facilities the Category 1 and 3 contact handled low-level radioactive mixed wastes that are currently in retrievable storage at Hanford and are forecast to be generated over the next 30 years by Hanford, and waste to be shipped to Hanford from about DOE sites. This volume provides an introduction to the ACDR process and the scope of the task along with a project summary of the facility, treatment technologies, cost, and schedule. Major areas of departure from the CDR are highlighted. Descriptions of the facility layout and operations are included.

  9. Concepts and Strategies for Transparency Monitoring of Nuclear Materials at the Back End of the Fuel/Weapons Cycle

    SciTech Connect

    COSTIN, LAURENCE; DAVIES, PETER; PREGENZER, ARIAN L.

    1999-10-01

    Representatives of the Department of Energy, the national laboratories, the Waste Isolation Pilot Plant (WIPP), and others gathered to initiate the development of broad-based concepts and strategies for transparency monitoring of nuclear materials at the back end of the fuel/weapons cycle, including both geologic disposal and monitored retrievable storage. The workshop focused on two key questions: ''Why should we monitor?'' and ''What should we monitor?'' These questions were addressed by identifying the range of potential stakeholders, concerns that stakeholders may have, and the information needed to address those concerns. The group constructed a strategic framework for repository transparency implementation, organized around the issues of safety (both operational and environmental), diversion (assuring legitimate use and security), and viability (both political and economic). Potential concerns of the international community were recognized as the possibility of material diversion, the multinational impacts of potential radionuclide releases, and public and political perceptions of unsafe repositories. The workshop participants also identified potential roles that the WIPP may play as a monitoring technology development and demonstration test-bed facility. Concepts for WIPP'S potential test-bed role include serving as (1) an international monitoring technology and development testing facility, (2) an international demonstration facility, and (3) an education and technology exchange center on repository transparency technologies.

  10. The CMS fast beams condition monitor back-end electronics based on MicroTCA technology: status and development

    NASA Astrophysics Data System (ADS)

    Zagozdzinska, Agnieszka A.; Dabrowski, Anne E.; Pozniak, Krzysztof T.

    2015-09-01

    The Fast Beams Condition Monitor (BCM1F), upgraded for LHC Run II, is used to measure the online luminosity and machine induced background for the CMS experiment. The detector consists of 24 single-crystal CVD diamond sensors that are read out with a custom fast front-end chip fabricated in 130 nm CMOS technology. Since the signals from the sensors are used for real time monitoring of the LHC conditions they are processed by dedicated back-end electronics to measure separately rates corresponding to LHC collision products, machine induced background and residual activation exploiting different arrival times. The system is built in MicroTCA technology and uses high speed analog-to-digital converters. In operational modes of high rates, consecutive events, spaced in time by less than 12.5 ns, may cause partially overlapping events. Hence, novel signal processing techniques are deployed to resolve overlapping peaks. The high accuracy qualification of the signals is crucial to determine the luminosity and the machine induced background rates for the CMS experiment and the LHC.

  11. Delta Modulation Technique for Improving the Sensitivity of Monobit Subsamplers in Radar and Coherent Receiver Applications

    DOE PAGES

    Rodenbeck, Christopher T.; Tracey, Keith J.; Barkley, Keith R.; ...

    2014-08-01

    This paper introduces a technique for improving the sensitivity of RF subsamplers in radar and coherent receiver applications. The technique, referred to herein as “delta modulation” (DM), feeds the time-average output of a monobit analog-to-digital converter (ADC) back to the ADC input, but with opposite polarity. Assuming pseudo-stationary modulation statistics on the sampled RF waveform, the feedback signal corrects for aggregate DC offsets present in the ADC that otherwise degrade ADC sensitivity. Two RF integrated circuits (RFICs) are designed to demonstrate the approach. One uses analog DM to create the feedback signal; the other uses digital DM to achieve themore » same result. A series of tests validates the designs. The dynamic time-domain response confirms the feedback loop’s basic operation. Measured output quantization imbalance, under noise-only input drive, significantly improves with the use of the DM circuit, even for large, deliberately induced DC offsets and wide temperature variation from -55°C to +85 °C. Examination of the corrected vs. uncorrected baseband spectrum under swept input signal-tonoise ratio (SNR) conditions demonstrates the effectiveness of this approach for realistic radar and coherent receiver applications. In conclusion, two-tone testing shows no impact of the DM technique on ADC linearity.« less

  12. Delta Modulation Technique for Improving the Sensitivity of Monobit Subsamplers in Radar and Coherent Receiver Applications

    SciTech Connect

    Rodenbeck, Christopher T.; Tracey, Keith J.; Barkley, Keith R.; DuVerneay, Brian B.

    2014-08-01

    This paper introduces a technique for improving the sensitivity of RF subsamplers in radar and coherent receiver applications. The technique, referred to herein as “delta modulation” (DM), feeds the time-average output of a monobit analog-to-digital converter (ADC) back to the ADC input, but with opposite polarity. Assuming pseudo-stationary modulation statistics on the sampled RF waveform, the feedback signal corrects for aggregate DC offsets present in the ADC that otherwise degrade ADC sensitivity. Two RF integrated circuits (RFICs) are designed to demonstrate the approach. One uses analog DM to create the feedback signal; the other uses digital DM to achieve the same result. A series of tests validates the designs. The dynamic time-domain response confirms the feedback loop’s basic operation. Measured output quantization imbalance, under noise-only input drive, significantly improves with the use of the DM circuit, even for large, deliberately induced DC offsets and wide temperature variation from -55°C to +85 °C. Examination of the corrected vs. uncorrected baseband spectrum under swept input signal-tonoise ratio (SNR) conditions demonstrates the effectiveness of this approach for realistic radar and coherent receiver applications. In conclusion, two-tone testing shows no impact of the DM technique on ADC linearity.

  13. Defect structure and electronic properties of SiOC:H films used for back end of line dielectrics

    SciTech Connect

    Pomorski, T. A.; Lenahan, P. M.; Bittel, B. C.; Mays, E.; Ege, C.; Bielefeld, J.; Michalak, D.; King, S. W.

    2014-06-21

    Back end of the line dielectrics (BEOL) with low dielectric constants, so called low-k dielectrics, are needed for current and future integrated circuit technology nodes. However, an understanding of the defects which limit reliability and cause leakage currents for these films is not yet developed. We primarily utilize conventional electron paramagnetic resonance (EPR) and leakage current measurements to investigate amorphous hydrogenated carbon doped oxide (a-SiOC:H) dielectrics, the most important in current BEOL technology. The resonance measurements were complemented by transmission Fourier-transform infra-red spectroscopy, x-ray reflectivity, and Rutherford backscattering measurements. Various compositions of a-SiOC:H films were deposited on 300 mm diameter Si (100) wafers. They exhibit a wide range of dielectric constant, composition, and porosity. Variations in deposition method, process chemistry, and post deposition curing were also investigated. We observe a remarkable range of paramagnetic defect populations within the films. In a large subset of the films with similar defect structure, we observe a strong correlation between carbon dangling bond paramagnetic defect densities and leakage currents, especially at lower electric fields. This correspondence strongly suggests that, in this subset, defects observed by EPR are in a large part responsible for the leakage currents at low electric fields. In addition, the results suggest that the observed defects likely limit the dielectric reliability in problems such as time dependent dielectric breakdown and stress induced leakage current in many of these films. However, the EPR results are complex, and a simple universal correspondence between defect populations and leakage does not seem to be present.

  14. On IEEE 802.15.6 IR-UWB receivers - simulations for DBPSK modulation.

    PubMed

    Niemelä, Ville; Hämäläinen, Matti; Iinatti, Jari

    2013-01-01

    In 2002, Federal Communications Commission (FCC) was the first in defining regulations for ultra wideband (UWB) communications followed by Europe and Japan some years later. Focusing on impulse radio (IR) UWB, in 2007 was the time for the first published standard targeting in personal area networks, released by the IEEE. The second IEEE released standard including UWB definitions is targeted for wireless body area networks (WBAN) and was published in 2012. As the wireless communications has been and will be passing through almost any levels in society, the natural step with WBAN is using it in different medical, healthcare and wellbeing applications. The arguments for these are related to the modern lifestyle, in which people have increasingly more free time and are more interested in taking care of their health and wellbeing. Another challenge is the population composition, i.e., aging in developed countries which call for new solutions and procedures, particularly from cost wise. In this paper, we are evaluating UWB receivers based on the IEEE 802.15.6 physical layer definitions and capable of detecting differentially encoded modulation. The evaluation is performed using two different WBAN channel models.

  15. Optical Receiver for Coherently Detected Pulse-Position Modulated Signals in the Presence of Atmospheric Turbulence

    NASA Astrophysics Data System (ADS)

    Munoz Fernandez, M.; Vilnrotter, V. A.

    2005-05-01

    Performance analysis and experimental verification of a coherent free-space optical communications receiver in the presence of simulated atmospheric turbulence is presented. Bit-error rate (BER) performance of ideal coherent detection is analyzed in Section II, and the laboratory equipment and experimental setup used to carry out these experiments are described. The key components include two lasers operating at a 1064-nm wavelength for use with coherent detection, a 16-element (4 x 4) focal-plane detector array, and a data acquisition and signal processing assembly needed to sample and collect the data and analyze the results. The detected signals are combined using the least-mean-square (LMS) algorithm. In Section III, convergence of the algorithm for experimentally obtained signal tones in the presence of atmospheric turbulence is demonstrated. In Section IV, adaptive combining of experimentally obtained heterodyned pulse-position modulated (PPM) signals with pulse-to-pulse coherence, in the presence of simulated spatial distortions resembling atmospheric turbulence, is demonstrated. The adaptively combined PPM signals are phased up via an LMS algorithm suitably optimized to operate with PPM in the presence of additive shot noise. A convergence analysis of the algorithm is presented, and results with both computer-simulated and experimentally obtained PPM signals are analyzed.

  16. The Air Force Manufacturing Technology (MANTECH): Technology transfer methodology as exemplified by the radar transmit/receive module program

    NASA Technical Reports Server (NTRS)

    Houpt, Tracy; Ridgely, Margaret

    1991-01-01

    The Air Force Manufacturing Technology program is involved with the improvement of radar transmit/receive modules for use in active phased array radars for advanced fighter aircraft. Improvements in all areas of manufacture and test of these modules resulting in order of magnitude improvements in the cost of and the rate of production are addressed, as well as the ongoing transfer of this technology to the Navy.

  17. Compact 100Gb/s DP-QPSK integrated receiver module employing three-dimensional assembly technology.

    PubMed

    Tanobe, H; Kurata, Y; Nakanishi, Y; Fukuyama, H; Itoh, M; Yoshida, E

    2014-03-10

    We demonstrate a compact 100 Gbit/s DP-QPSK receiver module that is only 18 mm (W) x 16 mm (D) x 2.8 mm (H). The module size is reduced by using a ball grid array (BGA) package with three-dimensional assembly technology and by applying a heterogeneous integrated PLC. Error-free DP-QPSK signal demodulation is successfully demonstrated.

  18. Reconfigurable digital coherent receiver for metro-access networks supporting mixed modulation formats and bit-rates

    NASA Astrophysics Data System (ADS)

    Caballero, Antonio; Gonzalez, Neil Guerrero; Arlunno, Valeria; Borkowski, Robert; Pham, Tien Thang; Rodes, Roberto; Zhang, Xu; Othman, Maisara Binti; Prince, Kamau; Yu, Xianbin; Jensen, Jesper Bevensee; Zibar, Darko; Monroy, Idelfonso Tafur

    2013-12-01

    A single, reconfigurable, digital coherent receiver is proposed and experimentally demonstrated for converged wireless and optical fiber transport. The capacity of reconstructing the full transmitted optical field allows for the demodulation of mixed modulation formats and bit-rates. We performed experimental validation of different modulation formats, including VCSEL based OOK, baseband QPSK, RoF OFDM and wireless IR-UWB over a 78 km deployed fiber link.

  19. Use of dilute hydrofluoric acid and deep eutectic solvent systems for back end of line cleaning in integrated circuit fabrication

    NASA Astrophysics Data System (ADS)

    Padmanabhan Ramalekshmi Thanu, Dinesh

    Fabrication of current generation integrated circuits involves the creation of multilevel copper/low-k dielectric structures during the back end of line processing. This is done by plasma etching of low-k dielectric layers to form vias and trenches, and this process typically leaves behind polymer-like post etch residues (PER) containing copper oxides, copper fluorides and fluoro carbons, on underlying copper and sidewalls of low-k dielectrics. Effective removal of PER is crucial for achieving good adhesion and low contact resistance in the interconnect structure, and this is accomplished using wet cleaning and rinsing steps. Currently, the removal of PER is carried out using semi-aqueous fluoride based formulations. To reduce the environmental burden and meet the semiconductor industry's environmental health and safety requirements, there is a desire to completely eliminate solvents in the cleaning formulations and explore the use of organic solvent-free formulations. The main objective of this work is to investigate the selective removal of PER over copper and low-k (Coral and Black DiamondRTM) dielectrics using all-aqueous dilute HF (DHF) solutions and choline chloride (CC) -- urea (U) based deep eutectic solvent (DES) system. Initial investigations were performed on plasma oxidized copper films. Copper oxide and copper fluoride based PER films representative of etch products were prepared by ashing g-line and deep UV photoresist films coated on copper in CF4/O2 plasma. PER removal process was characterized using scanning electron microscopy and X-ray photoelectron spectroscopy and verified using electrochemical impedance spectroscopy measurements. A PER removal rate of ~60 A/min was obtained using a 0.2 vol% HF (pH 2.8). Deaeration of DHF solutions improved the selectivity of PER over Cu mainly due to reduced Cu removal rate. A PER/Cu selectivity of ~20:1 was observed in a 0.05 vol% deaerated HF (pH 3). DES systems containing 2:1 U/CC removed PER at a rate of

  20. W-band Heterodyne Receiver Module with 27 K Noise Temperature

    NASA Technical Reports Server (NTRS)

    Gawande, R.; Reeves, R.; Cleary, K.; Readhead, A. C.; Gaier, T.; Kangaslahti, P.; Samoska, L.; Church, S.; Sieth, M.; Voll, P.; Harris, A.; Lai, R.; Sarkozy, S.

    2012-01-01

    We present noise temperature and gain measurements of a W-band heterodyne module populated with MMIC LNAs designed and fabricated using 35nm InP HEMT process. The module has a WR-10 waveguide input. GPPO connectors are used for the LO input and the I and and Q IF outputs. The module is tested at both ambient (300 K) and cryogenic (25 K) temperatures. At 25 K physical temperature, the module has a noise temperature in the range of 27-45 K over the frequency band of 75-111 GHz. The module gain varies between 15 dB and 27 dB. The band-averaged module noise temperature of 350 K and 33 K were measured over 80-110 GHz for the physical temperature of 300 K and 25 K, respectively. The resulting cooling factor is 10.6.

  1. Simple receiver with soft decision forward error correction for binary amplitude modulation

    NASA Astrophysics Data System (ADS)

    Konyshev, V. A.; Nanii, O. E.; Treshchikov, V. N.; Ubaydullaev, R. R.

    2015-06-01

    A simple receiver with soft decision forward error correction (FEC) based on two comparators is proposed. It is shown that the gain in the optical signal-to-noise ratio (OSNR), as compared with conventional receivers with hard decision FEC, can reach 0.5 dB. Some design variants of such detectors are presented.

  2. Simple receiver with soft decision forward error correction for binary amplitude modulation

    SciTech Connect

    Konyshev, V A; Treshchikov, V N; Ubaydullaev, R R

    2015-06-30

    A simple receiver with soft decision forward error correction (FEC) based on two comparators is proposed. It is shown that the gain in the optical signal-to-noise ratio (OSNR), as compared with conventional receivers with hard decision FEC, can reach 0.5 dB. Some design variants of such detectors are presented. (laser applications and other topics in quantum electronics)

  3. Transmitter and Translating Receiver Design For 64-ary Pulse Position Modulation (PPM)

    SciTech Connect

    Mendez, A J; Hernandez, V J; Gagliardi, R M; Bennett, C V

    2010-01-20

    This paper explores the architecture and design of an optically-implemented 64-ary PPM transmitter and direct-translating receiver that effectively translates incoming electrically-generated bit streams into optical PPM symbols (and vice-versa) at > 1 Gb/s data rates. The PPM transmitter is a cascade of optical switches operating at the frame rate. A corresponding receiver design is more difficult to architect and implement, since increasing data rates lead to correspondingly shorter decision times (slot times and frame times). We describe a solution in the form of a time-to-space mapping arrayed receiver that performs a translating algorithm represented as a code map. The technique for generating the code map is described, and the implementation of the receiver as a planar lightwave circuit is given. The techniques for implementing the transmitter and receiver can be generalized for any case of M-ary PPM.

  4. Transmitter and translating receiver design for 64-ary pulse position modulation (PPM)

    NASA Astrophysics Data System (ADS)

    Mendez, Antonio J.; Hernandez, Vincent J.; Gagliardi, Robert M.; Bennett, Corey V.

    2010-02-01

    This paper explores the architecture and design of an optically-implemented 64-ary PPM transmitter and direct-translating receiver that effectively translates incoming electrically-generated bit streams into optical PPM symbols (and vice-versa) at > 1 Gb/s data rates. The PPM transmitter is a cascade of optical switches operating at the frame rate. A corresponding receiver design is more difficult to architect and implement, since increasing data rates lead to correspondingly shorter decision times (slot times and frame times). We describe a solution in the form of a time-to-space mapping arrayed receiver that performs a translating algorithm represented as a code map. The technique for generating the code map is described, and the implementation of the receiver as a planar lightwave circuit is given. The techniques for implementing the transmitter and receiver can be generalized for any case of M-ary PPM.

  5. Dual-beam ELF wave generation as a function of power, frequency, modulation waveform, and receiver location

    NASA Astrophysics Data System (ADS)

    Agrawal, D.; Moore, R. C.

    2012-12-01

    Dual-beam ELF wave generation experiments performed at the High-frequency Active Auroral Research Program (HAARP) HF transmitter are used to investigate the dependence of the generated ELF wave magnitude on HF power, HF frequency, modulation waveform, and receiver location. During the experiments, two HF beams transmit simultaneously: one amplitude modulated (AM) HF beam modulates the conductivity of the lower ionosphere at ELF frequencies while a second HF beam broadcasts a continuous waveform (CW) signal, modifying the efficiency of ELF conductivity modulation and thereby the efficiency of ELF wave generation. We report experimental results for different ambient ionospheric conditions, and we interpret the observations in the context of a newly developed dual-beam HF heating model. A comparison between model predictions and experimental observations indicates that the theoretical model includes the essential physics involved in multifrequency HF heating of the lower ionosphere. In addition to the HF transmission parameters mentioned above, the model is used to predict the dependence of ELF wave magnitude on the polarization of the CW beam and on the modulation frequency of the modulated beam. We consider how these effects vary with ambientD-region electron density and electron temperature.

  6. Virtual Array Receiver Options for 64-ary Pulse Position Modulation (PPM)

    SciTech Connect

    Mendez, A J; Hernandez, V J; Gagliardi, R M; Bennett, C V

    2009-01-12

    NASA is developing technology for 64 64-ary PPM using relatively large PPM time slots (10 ns) an and relatively simple d electronic electronic-based receiver logic. In this paper we describe photonic photonics-based receiver options for the case of much higher data rates and inherently shorter decision times. The receivers take the form of virtual ( array or quadrant) arrays with associated comparison tests. Previously we explored this concept for 4-ary and 16-ary PPM at data rates of up to 10 Gb/s. The lessons learned are applied to the case of 64 64-ary PPM at 1.25 Gb/s s. Various receiver designs are compare, and t the optimum design, based on virtual array he arrays, is s, evaluated using numerical simulations.

  7. Waste Receiving and Processing Facility Module 2A: Advanced Conceptual Design Report. Volume 2

    SciTech Connect

    Not Available

    1994-03-01

    This volume presents the Total Estimated Cost (TEC) for the WRAP (Waste Receiving and Processing) 2A facility. The TEC is $81.9 million, including an overall project contingency of 25% and escalation of 13%, based on a 1997 construction midpoint. (The mission of WRAP 2A is to receive, process, package, certify, and ship for permanent burial at the Hanford site disposal facilities the Category 1 and 3 contact handled low-level radioactive mixed wastes that are currently in retrievable storage, and are forecast to be generated over the next 30 years by Hanford, and waste to be shipped to Hanford site from about 20 DOE sites.)

  8. Receiver Signal to Noise Ratios for IPDA Lidars Using Sine-wave and Pulsed Laser Modulation and Direct Detections

    NASA Technical Reports Server (NTRS)

    Sun, Xiaoli; Abshire, James B.

    2011-01-01

    Integrated path differential absorption (IPDA) lidar can be used to remotely measure the column density of gases in the path to a scattering target [1]. The total column gas molecular density can be derived from the ratio of the laser echo signal power with the laser wavelength on the gas absorption line (on-line) to that off the line (off-line). 80th coherent detection and direct detection IPDA lidar have been used successfully in the past in horizontal path and airborne remote sensing measurements. However, for space based measurements, the signal propagation losses are often orders of magnitude higher and it is important to use the most efficient laser modulation and detection technique to minimize the average laser power and the electrical power from the spacecraft. This paper gives an analysis the receiver signal to noise ratio (SNR) of several laser modulation and detection techniques versus the average received laser power under similar operation environments. Coherent detection [2] can give the best receiver performance when the local oscillator laser is relatively strong and the heterodyne mixing losses are negligible. Coherent detection has a high signal gain and a very narrow bandwidth for the background light and detector dark noise. However, coherent detection must maintain a high degree of coherence between the local oscillator laser and the received signal in both temporal and spatial modes. This often results in a high system complexity and low overall measurement efficiency. For measurements through atmosphere the coherence diameter of the received signal also limits the useful size of the receiver telescope. Direct detection IPDA lidars are simpler to build and have fewer constraints on the transmitter and receiver components. They can use much larger size 'photon-bucket' type telescopes to reduce the demands on the laser transmitter. Here we consider the two most widely used direct detection IPDA lidar techniques. The first technique uses two CW

  9. Receiver Architecture for 12.5 Gb/s 16-ary Pulse Position Modulation (PPM) Signaling

    SciTech Connect

    Mendez, A J; Gagliardi, R M; Hernandez, V J; Bennett, C V

    2008-07-11

    PPM is a signaling scheme that enables the transmission of multiple bits per symbol [1]. It has found favor in the regime of free space optical communications ('FSO' or 'Lasercom'); however, PPM has yet to be widely applied to fiber optic-based communications. Its limitation in fiber results from the exceedingly high bandwidth requirements needed to electronically process a directly detected pulse, especially as the symbol rate increases and the pulse width correspondingly decreases. As a solution, we introduced the concept of a virtual quadrant receiver for receiving 1.25 Gb/s 4-ary PPM, where photonic processing reduced the number of required electronic components [2]. In this paper, we extend these photonic process techniques to a 16-ary, 12.5 Gb/s (10 Gb/s plus 8B/10B line coding) PPM communications system for fiber optic avionics, wherein much of the receiver processing is enabled by techniques based on planar lightwave circuits (PLCs). The architecture is applicable to higher input data rates and M-ary PPM. In the following, we present the PPM encoding and decoding architectures and numerically simulated results.

  10. The sROD module for the ATLAS Tile Calorimeter Phase-II Upgrade Demonstrator

    NASA Astrophysics Data System (ADS)

    Carrió, F.; Castillo, V.; Ferrer, A.; Fiorini, L.; Hernández, Y.; Higón, E.; Mellado, B.; March, L.; Moreno, P.; Reed, R.; Solans, C.; Valero, A.; Valls, J. A.

    2014-02-01

    TileCal is the central hadronic calorimeter of the ATLAS experiment at the Large Hadron Collider (LHC) at CERN. The main upgrade of the LHC to increase the instantaneous luminosity is scheduled for 2022. The High Luminosity LHC, also called upgrade Phase-II, will imply a complete redesign of the read-out electronics in TileCal. In the new read-out architecture, the front-end electronics aims to transmit full digitized information to the back-end system in the counting rooms. Thus, the back-end system will also provide digital calibrated information with enhanced precision and granularity to the first level trigger to improve the trigger efficiencies. The demonstrator project is envisaged to qualify this new proposed architecture. A reduced part of the detector, 1/256 of the total, will be equipped with the new electronics during 2014 to evaluate the proposed architecture in real conditions. The upgraded Read-Out Driver (sROD) will be the core element of the back-end electronics in Phase-II. The sROD module is designed on a double mid-size AMC format and will operate under an AdvancedTCA framework. The module includes two Xilinx Series 7 Field Programmable Gate Arrays (FPGAs) for data receiving and processing, as well as the implementation of embedded systems. Related to optical connectors, the sROD uses 4 QSFPs to receive and transmit data from the front-end electronics and 1 Avago MiniPOD to send preprocessed data to the first level trigger system. An SFP module maintains the compatibility with the existing hardware. A complete description of the sROD module for the demonstrator including the main functionalities, circuit design and the control software and firmware will be presented.

  11. Immune inflammation indicators and implication for immune modulation strategies in advanced hepatocellular carcinoma patients receiving sorafenib

    PubMed Central

    Gardini, Andrea Casadei; Scarpi, Emanuela; Faloppi, Luca; Scartozzi, Mario; Silvestris, Nicola; Santini, Daniele; de Stefano, Giorgio; Marisi, Giorgia; Negri, Francesca V.; Foschi, Francesco Giuseppe; Valgiusti, Martina; Ercolani, Giorgio; Frassineti, Giovanni Luca

    2016-01-01

    We evalueted a systemic immune-inflammation index (SII), neutrophil-to-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) with the aim to explored their prognostic value in patients with advanced hepatocellular carcinoma (HCC) treated with sorafenib. 56 advanced HCC patients receiving sorafenib were available for our analysis. Lymphocyte, neutrophil and platelet were measured before beginning of treatment and after one month. Patient with SII ≥ 360 showed lower median PFS (2.6 vs. 3.9 months, P < 0.026) and OS (5.6 vs. 13.9 months, P = 0.027) with respect to patients with SII < 360. NLR ≥ 3 had a lower median PFS (2.6 vs. 3.3 months, P < 0.049) but not OS (5.6 vs. 13.9 months, P = 0.062) than those with NLR < 3. After adjusting for clinical covariates SII and NLR remained an independent prognostic factor for OS. The SII and NLR represent potential prognostic indicator in patients with advanced HCC treated with sorafenib. PMID:27613839

  12. An analysis of the back end of the nuclear fuel cycle with emphasis on high-level waste management, volume 1

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The programs and plans of the U.S. government for the "back end of the nuclear fuel cycle" were examined to determine if there were any significant technological or regulatory gaps and inconsistencies. Particular emphasis was placed on analysis of high-level nuclear waste management plans, since the permanent disposal of radioactive waste has emerged as a major factor in the public acceptance of nuclear power. The implications of various light water reactor fuel cycle options were examined including throwaway, stowaway, uranium recycle, and plutonium plus uranium recycle. The results of this study indicate that the U.S. program for high-level waste management has significant gaps and inconsistencies. Areas of greatest concern include: the adequacy of the scientific data base for geological disposal; programs for the the disposal of spent fuel rods; interagency coordination; and uncertainties in NRC regulatory requirements for disposal of both commercial and military high-level waste.

  13. Design of a Virtual Quadrant Receiver for 4-ary Pulse Position Modulation/Optical CDMA (4-ary PPM/O-CDMA)

    SciTech Connect

    Mendez, A J; Gagliardi, R M; Hernandez, V J; Bennett, C V; Lennon, W J

    2006-07-03

    We describe a receiver that performs optical code division multiple access (O-CDMA) decoding followed by pulse position modulation (PPM) symbol detection that behaves like a radar quadrant receiver. Simulations determine the impact of multi-access interference on symbol detection for up to 32 users.

  14. Predictors of Radiation Pneumonitis in Patients Receiving Intensity Modulated Radiation Therapy for Hodgkin and Non-Hodgkin Lymphoma

    SciTech Connect

    Pinnix, Chelsea C.; Smith, Grace L.; Milgrom, Sarah; Osborne, Eleanor M.; Reddy, Jay P.; Akhtari, Mani; Reed, Valerie; Arzu, Isidora; Allen, Pamela K.; Wogan, Christine F.; Fanale, Michele A.; Oki, Yasuhiro; Turturro, Francesco; Romaguera, Jorge; Fayad, Luis; Fowler, Nathan; Westin, Jason; Nastoupil, Loretta; Hagemeister, Fredrick B.; Rodriguez, M. Alma [Department of Lymphoma and others

    2015-05-01

    Purpose: Few studies to date have evaluated factors associated with the development of radiation pneumonitis (RP) in patients with Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL), especially in patients treated with contemporary radiation techniques. These patients represent a unique group owing to the often large radiation target volumes within the mediastinum and to the potential to receive several lines of chemotherapy that add to pulmonary toxicity for relapsed or refractory disease. Our objective was to determine the incidence and clinical and dosimetric risk factors associated with RP in lymphoma patients treated with intensity modulated radiation therapy (IMRT) at a single institution. Methods and Materials: We retrospectively reviewed clinical charts and radiation records of 150 consecutive patients who received mediastinal IMRT for HL and NHL from 2009 through 2013. Clinical and dosimetric predictors associated with RP according to Radiation Therapy Oncology Group (RTOG) acute toxicity criteria were identified in univariate analysis using the Pearson χ{sup 2} test and logistic multivariate regression. Results: Mediastinal radiation was administered as consolidation therapy in 110 patients with newly diagnosed HL or NHL and in 40 patients with relapsed or refractory disease. The overall incidence of RP (RTOG grades 1-3) was 14% in the entire cohort. Risk of RP was increased for patients who received radiation for relapsed or refractory disease (25%) versus those who received consolidation therapy (10%, P=.019). Several dosimetric parameters predicted RP, including mean lung dose of >13.5 Gy, V{sub 20} of >30%, V{sub 15} of >35%, V{sub 10} of >40%, and V{sub 5} of >55%. The likelihood ratio χ{sup 2} value was highest for V{sub 5} >55% (χ{sup 2} = 19.37). Conclusions: In using IMRT to treat mediastinal lymphoma, all dosimetric parameters predicted RP, although small doses to large volumes of lung had the greatest influence. Patients with relapsed

  15. Use of formulations based on choline chloride-malonic acid deep eutectic solvent for back end of line cleaning in integrated circuit fabrication

    NASA Astrophysics Data System (ADS)

    Taubert, Jenny

    Interconnection layers fabricated during back end of line processing in semiconductor manufacturing involve dry etching of a low-k material and deposition of copper and metal barriers to create copper/dielectric stacks. After plasma etching steps used to form the trenches and vias in the dielectric, post etch residues (PER) that consist of organic polymer, metal oxides and fluorides, form on top of copper and low-k dielectric sidewalls. Currently, most semiconductor companies use semi aqueous fluoride (SAF) based formulations containing organic solvent(s) for PER removal. Unfortunately, these formulations adversely impact the environmental health and safety (EHS) requirements of the semiconductor industry. Environmentally friendly "green" formulations, free of organic solvents, are preferred as alternatives to remove PER. In this work, a novel low temperature molten salt system, referred as deep eutectic solvent (DES) has been explored as a back end of line cleaning (BEOL) formulation. Specifically, the DES system comprised of two benign chemicals, malonic acid (MA) and choline chloride (CC), is a liquid at room temperature. In certain cases, the formulation was modified by the addition of glacial acetic acid (HAc). Using these formulations, selective removal of three types of PER generated by timed CF4/O2 etching of DUV PR films on Cu was achieved. Type I PER was mostly organic in character (fluorocarbon polymer type) and had a measured thickness of 160 nm. Type II PER was much thinner (25 nm) and consisted of a mixture of organic and inorganic compounds (copper fluorides). Further etching generated 17 nm thick Type III PER composed of copper fluorides and oxides. Experiments were also conducted on patterned structures. Cleaning was performed by immersing samples in a temperature controlled (30 or 40° C) double jacketed vessel for a time between 1 and 5 minutes. Effectiveness of cleaning was characterized using SEM, XPS and single frequency impedance measurements

  16. Modulation of circulating angiogenic factors and tumor biology by aerobic training in breast cancer patients receiving neoadjuvant chemotherapy.

    PubMed

    Jones, Lee W; Fels, Diane R; West, Miranda; Allen, Jason D; Broadwater, Gloria; Barry, William T; Wilke, Lee G; Masko, Elisabeth; Douglas, Pamela S; Dash, Rajesh C; Povsic, Thomas J; Peppercorn, Jeffrey; Marcom, P Kelly; Blackwell, Kimberly L; Kimmick, Gretchen; Turkington, Timothy G; Dewhirst, Mark W

    2013-09-01

    Aerobic exercise training (AET) is an effective adjunct therapy to attenuate the adverse side-effects of adjuvant chemotherapy in women with early breast cancer. Whether AET interacts with the antitumor efficacy of chemotherapy has received scant attention. We carried out a pilot study to explore the effects of AET in combination with neoadjuvant doxorubicin-cyclophosphamide (AC+AET), relative to AC alone, on: (i) host physiology [exercise capacity (VO2 peak), brachial artery flow-mediated dilation (BA-FMD)], (ii) host-related circulating factors [circulating endothelial progenitor cells (CEP) cytokines and angiogenic factors (CAF)], and (iii) tumor phenotype [tumor blood flow ((15)O-water PET), tissue markers (hypoxia and proliferation), and gene expression] in 20 women with operable breast cancer. AET consisted of three supervised cycle ergometry sessions/week at 60% to 100% of VO2 peak, 30 to 45 min/session, for 12 weeks. There was significant time × group interactions for VO2 peak and BA-FMD, favoring the AC+AET group (P < 0.001 and P = 0.07, respectively). These changes were accompanied by significant time × group interactions in CEPs and select CAFs [placenta growth factor, interleukin (IL)-1β, and IL-2], also favoring the AC+AET group (P < 0.05). (15)O-water positron emission tomography (PET) imaging revealed a 38% decrease in tumor blood flow in the AC+AET group. There were no differences in any tumor tissue markers (P > 0.05). Whole-genome microarray tumor analysis revealed significant differential modulation of 57 pathways (P < 0.01), including many that converge on NF-κB. Data from this exploratory study provide initial evidence that AET can modulate several host- and tumor-related pathways during standard chemotherapy. The biologic and clinical implications remain to be determined.

  17. Vicious circle of acute radiation toxicities and weight loss predicts poor prognosis for nasopharyngeal carcinoma patients receiving intensity modulated radiotherapy

    PubMed Central

    Li, Guo; Jiang, Xiong-ying; Qiu, Bo; Shen, Lu-Jun; Chen, Chen; Xia, Yun-Fei

    2017-01-01

    Background: Weight loss during radiotherapy has been known as a negative prognostic factor for nasopharyngeal carcinoma (NPC) patients, but the factors related to weight loss during radiotherapy were not fully understood. Methods: A total of 322 newly diagnosed NPC patients receiving intensity modulated radiotherapy (IMRT) in Sun Yat-sen University Cancer Center between June 2002 and August 2006 were enrolled. Kaplan-Meier methods and log-rank test were applied for survival analysis; a multiple regression was used to identify the factors related to weight loss during radiotherapy. Results: The mean and median values of weight loss (%) during radiotherapy were 6.85% and 6.70%. NPC patients with critical weight loss (> 5.4%) have poorer overall survival (OS) and distant metastasis-free survival (DMFS) than the patients without critical weight loss (p = 0.002 and 0.021, respectively). Pre-radiotherapy weight, acute mucosal toxicity, acute pharynx and esophagus toxicity, and acute upper gastrointestinal toxicity were related to the weight loss during radiotherapy independently (p = 0.01, p < 0.001, p < 0.001, and p = 0.009, respectively). Conclusions: Acute radiation toxicities had significant and independent impact on weight loss during radiotherapy. The vicious circle of acute radiation toxicities and weight loss had bad effect on prognosis of NPC patients. PMID:28382146

  18. A fully-integrated 12.5-Gb/s 850-nm CMOS optical receiver based on a spatially-modulated avalanche photodetector.

    PubMed

    Lee, Myung-Jae; Youn, Jin-Sung; Park, Kang-Yeob; Choi, Woo-Young

    2014-02-10

    We present a fully integrated 12.5-Gb/s optical receiver fabricated with standard 0.13-µm complementary metal-oxide-semiconductor (CMOS) technology for 850-nm optical interconnect applications. Our integrated optical receiver includes a newly proposed CMOS-compatible spatially-modulated avalanche photodetector, which provides larger photodetection bandwidth than previously reported CMOS-compatible photodetectors. The receiver also has high-speed CMOS circuits including transimpedance amplifier, DC-balanced buffer, equalizer, and limiting amplifier. With the fabricated optical receiver, detection of 12.5-Gb/s optical data is successfully achieved at 5.8 pJ/bit. Our receiver achieves the highest data rate ever reported for 850-nm integrated CMOS optical receivers.

  19. A common neural element receiving rhythmic arm and leg activity as assessed by reflex modulation in arm muscles.

    PubMed

    Sasada, Syusaku; Tazoe, Toshiki; Nakajima, Tsuyoshi; Futatsubashi, Genki; Ohtsuka, Hiroyuki; Suzuki, Shinya; Zehr, E Paul; Komiyama, Tomoyoshi

    2016-04-01

    Neural interactions between regulatory systems for rhythmic arm and leg movements are an intriguing issue in locomotor neuroscience. Amplitudes of early latency cutaneous reflexes (ELCRs) in stationary arm muscles are modulated during rhythmic leg or arm cycling but not during limb positioning or voluntary contraction. This suggests that interneurons mediating ELCRs to arm muscles integrate outputs from neural systems controlling rhythmic limb movements. Alternatively, outputs could be integrated at the motoneuron and/or supraspinal levels. We examined whether a separate effect on the ELCR pathways and cortico-motoneuronal excitability during arm and leg cycling is integrated by neural elements common to the lumbo-sacral and cervical spinal cord. The subjects performed bilateral leg cycling (LEG), contralateral arm cycling (ARM), and simultaneous contralateral arm and bilateral leg cycling (A&L), while ELCRs in the wrist flexor and shoulder flexor muscles were evoked by superficial radial (SR) nerve stimulation. ELCR amplitudes were facilitated by cycling tasks and were larger during A&L than during ARM and LEG. A low stimulus intensity during ARM or LEG generated a larger ELCR during A&L than the sum of ELCRs during ARM and LEG. We confirmed this nonlinear increase in single motor unit firing probability following SR nerve stimulation during A&L. Furthermore, motor-evoked potentials following transcranial magnetic and electrical stimulation did not show nonlinear potentiation during A&L. These findings suggest the existence of a common neural element of the ELCR reflex pathway that is active only during rhythmic arm and leg movement and receives convergent input from contralateral arms and legs.

  20. Methylatable Signaling Helix Coordinated Inhibitory Receiver Domain in Sensor Kinase Modulates Environmental Stress Response in Bacillus Cereus

    PubMed Central

    Chen, Jung-Chi; Liu, Jyung-Hurng; Hsu, Duen-Wei; Shu, Jwu-Ching; Chen, Chien-Yen; Chen, Chien-Cheng

    2015-01-01

    σB, an alternative transcription factor, controls the response of the cell to a variety of environmental stresses in Bacillus cereus. Previously, we reported that RsbM negatively regulates σB through the methylation of RsbK, a hybrid sensor kinase, on a signaling helix (S-helix). However, RsbK comprises a C-terminal receiver (REC) domain whose function remains unclear. In this study, deletion of the C-terminal REC domain of RsbK resulted in high constitutive σB expression independent of environmental stimuli. Thus, the REC domain may serve as an inhibitory element. Mutagenic substitution was employed to modify the putative phospho-acceptor residue D827 in the REC domain of RsbK. The expression of RsbKD827N and RsbKD827E exhibited high constitutive σB, indicating that D827, if phosphorylatable, possibly participates in σB regulation. Bacterial two-hybrid analyses demonstrated that RsbK forms a homodimer and the REC domain interacts mainly with the histidine kinase (HK) domain and partly with the S-helix. In particular, co-expression of RsbM strengthens the interaction between the REC domain and the S-helix. Consistently, our structural model predicts a significant interaction between the HK and REC domains of the RsbK intradimer. Here, we demonstrated that coordinated the methylatable S-helix and the REC domain of RsbK is functionally required to modulate σB-mediated stress response in B. cereus and maybe ubiquitous in microorganisms encoded RsbK-type sensor kinases. PMID:26379238

  1. A Low Distortion 3rd-Order Continuous-Time Delta-Sigma Modulator for a Worldwide Digital TV-Receiver

    NASA Astrophysics Data System (ADS)

    Obata, Koji; Matsukawa, Kazuo; Mitani, Yosuke; Takayama, Masao; Tokunaga, Yusuke; Sakiyama, Shiro; Dosho, Shiro

    This paper presents a low distortion 3rd-order continuous-time delta-sigma modulator for a worldwide digital TV-receiver whose peak SNDR is 69.8dB and SNR is 70.2dB under 1V power supply. To enhance SNDR performance, the mechanisms to occur harmonic distortions at feedback current-steering DAC and flash ADC have been analyzed. A low power tuning system using RC-relaxation oscillator has been developed in order to achieve high yield against PVT variations. A 3rd-order modulator with modified single opamp resonator contributes to cost reduction by realizing a very compact circuit. Reduction schemes of the distortions enabled the modulator to achieve FOM of 0.18pJ/conv-step.

  2. The brain is not a radio receiver for wireless phone signals: Human tissue does not demodulate a modulated radiofrequency carrier

    NASA Astrophysics Data System (ADS)

    Davis, Christopher C.; Balzano, Quirino

    2010-11-01

    It has been suggested that the low frequency modulations of the radiofrequency (RF) signal from a wireless phone could be demodulated by human tissue. If this occurred it could lead to interactions with ions in the tissue, with possible biological consequences. In recent experiments it has been shown that biological cells do not exhibit significant electrical nonlinearity to be able to demodulate low frequency signals present as modulations of a RF carrier. This makes irrelevant any hypothetical interactions between RF electromagnetic waves and biological systems involving such demodulation mechanisms. Your wireless phone is not an athermal hazard to your brain.

  3. Design and Evaluation of a Virtual Quadrant Receiver for 4-ary Pulse Position Modulation/Optical Code Division Multiple Access (4-ary PPM/O-CDMA)

    SciTech Connect

    Mendez, A J; Hernandez, V J; Gagliardi, R M; Bennett, C V

    2006-12-29

    M-ary pulse position modulation (M-ary PPM) is an alternative to on-off-keying (OOK) that transmits multiple bits as a single symbol occupying a frame of M slots. PPM does not require thresholding as in OOK signaling, instead performing a comparison test among all slots in a frame to make the slot decision. Combining PPM with optical code division multiple access (PPM/O-CDMA) adds the benefit of supporting multiple concurrent, asynchronous bursty PPM users. While the advantages of PPM/O-CDMA are well known, implementing a receiver that performs comparison test can be difficult. This paper describes the design of a novel array receiver for M-ary PPM/O-CDMA (M = 4) where the received signal is mapped onto an xy-plane whose quadrants define the PPM slot decision by means of an associated control law. The receiver does not require buffering or nonlinear operations. In this paper we describe a planar lightwave circuit (PLCs) implementation of the receiver. We give detailed numerical simulations that test the concept and investigate the effects of multi-access interference (MAI) and optical beat interference (OBI) on the slot decisions. These simulations provide guidelines for subsequent experimental measurements that will be described.

  4. Probability of error analysis of digital partial response continuous phase modulation with two-bit differential detection and offset receiver diversity in fast Rayleigh fading channels

    NASA Astrophysics Data System (ADS)

    Elnoubi, Said M.

    1990-06-01

    The performance of constant envelope digital partial response continuous phase modulation (PRCPM) with two-bit differential detection and offset receiver diversity is theoretically analyzed in fast Rayleigh fading channels. A simple closed-form expression for the probability of error is derived and evaluated for cases of practical interest to researchers and designers of land mobile radio systems. It is shown that the dynamic bit error rate (BER) performance is considerably improved using the offset diversity scheme. Thus, many PRCPM signals having a compact power spectrum can be used in future digital mobile radio systems.

  5. PAPR reduction and receiver sensitivity improvement in 16QAM-OFDM RoF system using DMT modulation and BTN-PS technique

    NASA Astrophysics Data System (ADS)

    Shao, Yufeng

    2016-03-01

    In this letter, we present the generation, the peak-to average power ratio (PAPR) reduction, the heterodyne detection, the self-mixing reception, and the transmission performance evaluation of 16QAM-OFDM signals in 60 GHz radio over fiber (RoF) system using Discrete multitone (DMT) modulation and Better Than Nyquist pulse shaping (BTN-PS) technique. DMT modulation is introduced in the RoF system, in-phase and quadrature (IQ) will not be required using BTN-PS method, and the computation complexity is much lower than other published techniques for reduced PAPR in the RoF system. In the experiment, 5 Gb/s 16QAM-OFDM downlink signals are transmitted over 42 km SMF-28 and a 0.4 m wireless channel. The experimental results show that the receiver sensitivity is effectively enhanced using this method. Therefore, the introduced BTN-PS technique and its application is a competitive scheme for reducing PAPR, and enhancing the receiver sensitivity in future RoF system.

  6. Modulation of Endothelial Injury Biomarkers by Traditional Chinese Medicine LC in Systemic Lupus Erythematosus Patients Receiving Standard Treatments.

    PubMed

    Chang, Hen-Hong; Luo, Shue-Fen; Hsue, Yin-Tzu; Chang, Ching-Mao; Lee, Tzung-Yan; Huang, Yu-Chuen; Hsu, Ming-Ling; Chen, Yu-Jen

    2016-02-05

    LC is an herbal remedy effectively reduced therapeutic dosage of glucocorticoid for systemic lupus erythematosus (SLE) patients in clinical trial (ISRCTN81818883). This translational research examined the impact of LC on biomarkers of endothelial injury in the enrolled subjects. Fifty seven patients with SLE were randomized to receive standard treatment without or with LC supplements. Blood samples were taken serially for quantification of endothelial progenitor cells (EPCs), circulating endothelial cells (CECs) and serological factors. The proportion of EPCs in the placebo group continued to increase during trial and was further elevated after withdrawal of standard treatment. The EPC ratio of LC group remained stationary during the entire observation period. The CEC ratio in placebo group exhibited an increasing trend whereas that in LC group declined. The ratio of apoptotic CECs had an increasing trend in both groups, to a lesser extent in LC group. After treatment, the levels of VEGF and IL-18 have a trend declined to a level lower in the LC group than the placebo group. No significant alteration was noted in serum levels of IFN-α, IL-1β and IL-6. The reduction of the steroid dosage by adding LC might be correlated with less extensive endothelial injury in SLE patients.

  7. Impact of Chemotherapy on Normal Tissue Complication Probability Models of Acute Hematologic Toxicity in Patients Receiving Pelvic Intensity Modulated Radiation Therapy

    SciTech Connect

    Bazan, Jose G.; Luxton, Gary; Kozak, Margaret M.; Anderson, Eric M.; Hancock, Steven L.; Kapp, Daniel S.; Kidd, Elizabeth A.; Koong, Albert C.; Chang, Daniel T.

    2013-12-01

    Purpose: To determine how chemotherapy agents affect radiation dose parameters that correlate with acute hematologic toxicity (HT) in patients treated with pelvic intensity modulated radiation therapy (P-IMRT) and concurrent chemotherapy. Methods and Materials: We assessed HT in 141 patients who received P-IMRT for anal, gynecologic, rectal, or prostate cancers, 95 of whom received concurrent chemotherapy. Patients were separated into 4 groups: mitomycin (MMC) + 5-fluorouracil (5FU, 37 of 141), platinum ± 5FU (Cis, 32 of 141), 5FU (26 of 141), and P-IMRT alone (46 of 141). The pelvic bone was contoured as a surrogate for pelvic bone marrow (PBM) and divided into subsites: ilium, lower pelvis, and lumbosacral spine (LSS). The volumes of each region receiving 5-40 Gy were calculated. The endpoint for HT was grade ≥3 (HT3+) leukopenia, neutropenia or thrombocytopenia. Normal tissue complication probability was calculated using the Lyman-Kutcher-Burman model. Logistic regression was used to analyze association between HT3+ and dosimetric parameters. Results: Twenty-six patients experienced HT3+: 10 of 37 (27%) MMC, 14 of 32 (44%) Cis, 2 of 26 (8%) 5FU, and 0 of 46 P-IMRT. PBM dosimetric parameters were correlated with HT3+ in the MMC group but not in the Cis group. LSS dosimetric parameters were well correlated with HT3+ in both the MMC and Cis groups. Constrained optimization (0received. Patients receiving P-IMRT ± 5FU have better bone marrow tolerance than those receiving irradiation concurrent with either Cis or MMC. Treatment with MMC has a lower TD{sub 50} and more steeply rising normal tissue complication probability curve compared with treatment with Cis. Dose tolerance of PBM and the LSS subsite may be lower for

  8. Risk of Late Toxicity in Men Receiving Dose-Escalated Hypofractionated Intensity Modulated Prostate Radiation Therapy: Results From a Randomized Trial

    SciTech Connect

    Hoffman, Karen E. Voong, K. Ranh; Pugh, Thomas J.; Skinner, Heath; Levy, Lawrence B.; Takiar, Vinita; Choi, Seungtaek; Du, Weiliang; Frank, Steven J.; Johnson, Jennifer; Kanke, James; Kudchadker, Rajat J.; Lee, Andrew K.; Mahmood, Usama; McGuire, Sean E.; Kuban, Deborah A.

    2014-04-01

    Objective: To report late toxicity outcomes from a randomized trial comparing conventional and hypofractionated prostate radiation therapy and to identify dosimetric and clinical parameters associated with late toxicity after hypofractionated treatment. Methods and Materials: Men with localized prostate cancer were enrolled in a trial that randomized men to either conventionally fractionated intensity modulated radiation therapy (CIMRT, 75.6 Gy in 1.8-Gy fractions) or to dose-escalated hypofractionated IMRT (HIMRT, 72 Gy in 2.4-Gy fractions). Late (≥90 days after completion of radiation therapy) genitourinary (GU) and gastrointestinal (GI) toxicity were prospectively evaluated and scored according to modified Radiation Therapy Oncology Group criteria. Results: 101 men received CIMRT and 102 men received HIMRT. The median age was 68, and the median follow-up time was 6.0 years. Twenty-eight percent had low-risk, 71% had intermediate-risk, and 1% had high-risk disease. There was no difference in late GU toxicity in men treated with CIMRT and HIMRT. The actuarial 5-year grade ≥2 GU toxicity was 16.5% after CIMRT and 15.8% after HIMRT (P=.97). There was a nonsignificant numeric increase in late GI toxicity in men treated with HIMRT compared with men treated with CIMRT. The actuarial 5-year grade ≥2 GI toxicity was 5.1% after CIMRT and 10.0% after HIMRT (P=.11). In men receiving HIMRT, the proportion of rectum receiving 36.9 Gy, 46.2 Gy, 64.6 Gy, and 73.9 Gy was associated with the development of late GI toxicity (P<.05). The 5-year actuarial grade ≥2 GI toxicity was 27.3% in men with R64.6Gy ≥ 20% but only 6.0% in men with R64.6Gy < 20% (P=.016). Conclusions: Dose-escalated IMRT using a moderate hypofractionation regimen (72 Gy in 2.4-Gy fractions) can be delivered safely with limited grade 2 or 3 late toxicity. Minimizing the proportion of rectum that receives moderate and high dose decreases the risk of late rectal toxicity after this

  9. Spaceborne receivers: Basic principles

    NASA Technical Reports Server (NTRS)

    Stacey, J. M.

    1984-01-01

    The underlying principles of operation of microwave receivers for space observations of planetary surfaces were examined. The design philosophy of the receiver as it is applied to operate functionally as an efficient receiving system, the principle of operation of the key components of the receiver, and the important differences among receiver types are explained. The operating performance and the sensitivity expectations for both the modulated and total power receiver configurations are outlined. The expressions are derived from first principles and are developed through the important intermediate stages to form practicle and easily applied equations. The transfer of thermodynamic energy from point to point within the receiver is illustrated. The language of microwave receivers is applied statistics.

  10. Real-time software receiver

    NASA Technical Reports Server (NTRS)

    Ledvina, Brent M. (Inventor); Psiaki, Mark L. (Inventor); Powell, Steven P. (Inventor); Kintner, Jr., Paul M. (Inventor)

    2006-01-01

    A real-time software receiver that executes on a general purpose processor. The software receiver includes data acquisition and correlator modules that perform, in place of hardware correlation, baseband mixing and PRN code correlation using bit-wise parallelism.

  11. Real-time software receiver

    NASA Technical Reports Server (NTRS)

    Ledvina, Brent M. (Inventor); Psiaki, Mark L. (Inventor); Powell, Steven P. (Inventor); Kintner, Jr., Paul M. (Inventor)

    2007-01-01

    A real-time software receiver that executes on a general purpose processor. The software receiver includes data acquisition and correlator modules that perform, in place of hardware correlation, baseband mixing and PRN code correlation using bit-wise parallelism.

  12. CALUTRON RECEIVER

    DOEpatents

    Barnes, S.W.

    1959-06-16

    An improved receiver and receiver mount for calutrons are described. The receiver can be manipulated from outside the tank by a single control to position it with respect to the beam. A door can be operated exteriorly also to prevent undesired portions of the beam from entering the receiver. The receiver has an improved pocket which is more selective in the ions collected. (T.R.H.)

  13. The C-reactive Protein/Albumin Ratio Is an independent Prognostic Factor for Overall Survival in Patients with Nasopharyngeal Carcinoma Receiving Intensity-Modulated Radiotherapy

    PubMed Central

    Tao, Chang-Juan; Chen, Yuan-Yuan; Jiang, Feng; Feng, Xing-Lai; Jin, Qi-Feng; Jin, Ting; Piao, Yong-Feng; Chen, Xiao-Zhong

    2016-01-01

    This study aims to investigate the prognostic value of the C-reactive protein/albumin (CRP/ALB) ratio in nasopharyngeal carcinoma (NPC) in the intensity-modulated radiotherapy (IMRT) era. A total of 719 patients with NPC treated between January 2007 and December 2012 were retrospectively reviewed. Serum albumin and CRP levels were measured before treatment. The associations between the CRP/ALB ratio and clinicopathological parameters were analyzed. Multivariate analyses using the Cox proportional hazards model were performed to identify significant prognostic factors associated with overall survival (OS). The prognostic value of the CRP/ALB ratio was determined using receiver operating characteristic (ROC) curve analysis. The optimal CRP/ALB ratio cutoff value was 0.141. High CRP/ALB ratio was significantly associated with older age (P < 0.001), more advanced T category (P < 0.001) and advanced TNM stage (P = 0.024). Patients with an elevated CRP/ALB ratio (≥ 0.141) had poorer OS than those with a CRP/ALB ratio < 0.141 (5-year OS rates: 91.9% vs. 78.1%; P < 0.001). Multivariate analysis suggested clinical T category [hazard ratio (HR) 2.284; 95% confidence interval (CI), 1.429-3.652; P = 0.001]; clinical N category (HR 1.575; 95% CI, 1.007-2.464; P = 0.047) and CRP/ALB ratio (HR 2.173; 95% CI, 1.128-3.059; P = 0.015) were independently associated with OS. In conclusion, pretreatment CRP/ALB ratio is an objective biomarker with significant prognostic value for OS in NPC. The CRP/ALB ratio can enhance conventional TNM staging to stratify patients and may help facilitate individualized treatment of high-risk cases. PMID:27877215

  14. The C-reactive Protein/Albumin Ratio Is an independent Prognostic Factor for Overall Survival in Patients with Nasopharyngeal Carcinoma Receiving Intensity-Modulated Radiotherapy.

    PubMed

    Tao, Chang-Juan; Chen, Yuan-Yuan; Jiang, Feng; Feng, Xing-Lai; Jin, Qi-Feng; Jin, Ting; Piao, Yong-Feng; Chen, Xiao-Zhong

    2016-01-01

    This study aims to investigate the prognostic value of the C-reactive protein/albumin (CRP/ALB) ratio in nasopharyngeal carcinoma (NPC) in the intensity-modulated radiotherapy (IMRT) era. A total of 719 patients with NPC treated between January 2007 and December 2012 were retrospectively reviewed. Serum albumin and CRP levels were measured before treatment. The associations between the CRP/ALB ratio and clinicopathological parameters were analyzed. Multivariate analyses using the Cox proportional hazards model were performed to identify significant prognostic factors associated with overall survival (OS). The prognostic value of the CRP/ALB ratio was determined using receiver operating characteristic (ROC) curve analysis. The optimal CRP/ALB ratio cutoff value was 0.141. High CRP/ALB ratio was significantly associated with older age (P < 0.001), more advanced T category (P < 0.001) and advanced TNM stage (P = 0.024). Patients with an elevated CRP/ALB ratio (≥ 0.141) had poorer OS than those with a CRP/ALB ratio < 0.141 (5-year OS rates: 91.9% vs. 78.1%; P < 0.001). Multivariate analysis suggested clinical T category [hazard ratio (HR) 2.284; 95% confidence interval (CI), 1.429-3.652; P = 0.001]; clinical N category (HR 1.575; 95% CI, 1.007-2.464; P = 0.047) and CRP/ALB ratio (HR 2.173; 95% CI, 1.128-3.059; P = 0.015) were independently associated with OS. In conclusion, pretreatment CRP/ALB ratio is an objective biomarker with significant prognostic value for OS in NPC. The CRP/ALB ratio can enhance conventional TNM staging to stratify patients and may help facilitate individualized treatment of high-risk cases.

  15. CALUTRON RECEIVER

    DOEpatents

    Brunk, W.O.

    1959-09-29

    A description is given for an improved calutron receiver having a face plate lying at an angle to the direction of the entering ion beams but having an opening, the plane of which is substantially perpendicular to that of the entering ion beams. By so positioning the opening in the receiver, the effective area through which the desired material may enter the receiver is increased, and at the same time the effective area through which containattng material may enter the receiver is reduced.

  16. CALUTRON RECEIVER

    DOEpatents

    York, H.F.

    1959-07-01

    A receiver construction is presented for calutrons having two or more ion sources and an individual receiver unit for each source. Design requirements dictate that the face plate defining the receiver entrance slots be placed at an angle to the approaching beam, which means that ions striking the face plate are likely to be scattcred into the entrance slots of other receivers. According to the present invention, the face plate has a surface provided with parallel ridges so disposed that one side only of each ridge's exposed directly to the ion beam. The scattered ions are directed away from adjacent receivers by the ridges on the lace plate.

  17. Multichannel homodyne receiver

    DOEpatents

    Landt, Jeremy A.

    1982-01-01

    A homodyne radar transmitter/receiver device which produces a single combined output which contains modulated backscatter information for all phase conditions of both modulated and unmodulated backscatter signals. The device utilizes taps along coaxial transmission lines, strip transmission line, and waveguides which are spaced by 1/8 wavelength or 1/6 wavelength, etc. This greatly reduces costs by eliminating separate transmission and reception antennas and an expensive arrangement of power splitters and mixers utilized in the prior art.

  18. Multichannel homodyne receiver

    DOEpatents

    Landt, J.A.

    1981-01-19

    A homodyne radar transmitter/receiver device which produces a single combined output which contains modulated backscatter information for all phase conditions of both modulated and unmodulated backscatter signals is described. The device utilizes taps along coaxial transmission lines, strip transmission line, and waveguides which are spaced by 1/8 wavelength or 1/6 wavelength, etc. This greatly reduces costs by eliminating separate transmission and reception antennas and an expensive arrangement of power splitters and mixers utilized in the prior art.

  19. CALUTRON RECEIVERS

    DOEpatents

    Schmidt, F.H.; Stone, K.F.

    1958-09-01

    S>This patent relates to improvements in calutron devices and, more specifically, describes a receiver fer collecting the ion curreot after it is formed into a beam of non-homogeneous isotropic cross-section. The invention embodies a calutron receiver having an ion receiving pocket for separately collecting and retaining ions traveling in a selected portion of the ion beam and anelectrode for intercepting ions traveling in another selected pontion of the ion beam. The electrode is disposed so as to fix the limit of one side of the pontion of the ion beam admitted iato the ion receiving pocket.

  20. Data-fusion receiver

    SciTech Connect

    Gabelmann, Jeffrey M.; Kattner, J. Stephen; Houston, Robert A.

    2006-12-19

    This invention is an ultra-low frequency electromagnetic telemetry receiver which fuses multiple input receive sources to synthesize a decodable message packet from a noise corrupted telemetry message string. Each block of telemetry data to be sent to the surface receiver from a borehole tool is digitally encoded into a data packet prior to transmission. The data packet is modulated onto the ULF EM carrier wave and transmitted from the borehole to the surface and then are simultaneously detected by multiple receive sensors disbursed within the rig environment. The receive sensors include, but are not limited to, electric field and magnetic field sensors. The spacing of the surface receive elements is such that noise generators are unequally coupled to each receive element due to proximity and/or noise generator type (i.e. electric or magnetic field generators). The receiver utilizes a suite of decision metrics to reconstruct the original, non noise-corrupted data packet from the observation matrix via the estimation of individual data frames. The receiver will continue this estimation process until: 1) the message validates, or 2) a preset "confidence threshold" is reached whereby frames within the observation matrix are no longer "trusted".

  1. Dehydrated citrus pulp alters feedlot performance of crossbred heifers during the receiving period and modulates serum metabolite concentrations pre- and post-endotoxin challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    English x Continental heifers (n=180) were sourced in two loads (188.7 ± 18.0 kilograms and 225.2 ± 22.2 kilograms body weight, respectively) from commercial auction barns to study the effects of feeding dehydrated citrus pulp (DCP) on feedlot performance of newly received heifers. A completely ran...

  2. Photon-counting 1.55 microm optical communications with pulse-position modulation and a multimode upconversion single-photon receiver.

    PubMed

    Albota, Marius A; Robinson, Bryan S

    2010-08-01

    We report single-photon frequency upconversion of multimode light from 1.55 to 0.532microm and demonstrate an end-to-end optical link that emulates photon-starved communications and atmospheric propagation. Using 64-ary pulse-position modulation and a half-rate serially concatenated turbo code we achieve a decoded efficiency of 0.3 detected photons/bit.

  3. Module Evaluation

    DTIC Science & Technology

    2006-02-01

    various testing methodologies for the evaluation and characterization of Transmit /Receive (T/R) modules for phased array radars. Discussed are techniques...for characterizing T/R modules in transmit and receive modes under ideal and emulated operation environments. Further, techniques for life testing...characteristics of T/R modules developed during the early and mid 1980’s. Data provided shows the performance in terms of gain and phase for both transmit

  4. CALUTRON RECEIVER

    DOEpatents

    Barnes, S.W.

    1959-08-25

    An improvement in a calutron receiver for collecting the isotopes ts described. The electromagnetic separation of the isotopes produces a mass spectrum of closely adjacent beams of ions at the foci regions, and a dividing wall between the two pockets is arranged at an angle. Substantially all of the tons of the less abundant isotope enter one of the pockets and strike one side of the wall directly, while substantially none of the tons entering the other pocket strikes the wall directly.

  5. VXI based multibunch detector and QPSK modulator for the PEP-II/ALS/DA{Phi}NE longitudinal feedback system

    SciTech Connect

    Young, A.; Fox, J.; Teytelman, D.

    1997-04-01

    The PEP-II/ALS/DA{Phi}NE feedback systems are complex systems implemented using analog, digital and microwave circuits. The VXI hardware implementation for the Front-end and Back-end analog processing modules is presented. The Front-end module produces a baseband beam phase signal from pickups using a microwave tone burst generator. The Back-end VXI module generates an AM/QPSK modulated signal from a baseband correction signal computed in a digital signal processor. These components are implemented in VXI packages that allow a wide spectrum of system functions including a 120 MHz bandwidth rms detector, reference phase servo, woofer link to the RF control system, standard VXI status/control, and user defined registers. The details of the design and implementation of the VXI modules including performance characteristics are presented.

  6. Receiver System Analysis and Optimization

    DTIC Science & Technology

    2013-01-01

    True Top-Down Design Methodology .................................. 5 Figure 4. Generic 16- QAM direct-conversion receiver...ADC 16- QAM decoder Figure 4. Generic 16- QAM direct-conversion receiver Complex digitally generated signals defy traditional spreadsheet...Intercept Point Three QAM Quadrature Amplitude Modulation SNR Signal-to-Noise Ratio USAF USR VCO United States Air Force Upsampling Ratio Voltage Controlled Oscillator

  7. A Wideband Dual-Antenna Receiver for Wireless Recording From Animals Behaving in Large Arenas

    PubMed Central

    Lee, Seung Bae; Yin, Ming; Manns, Joseph R.

    2014-01-01

    A low-noise wideband receiver (Rx) is presented for a multichannel wireless implantable neural recording (WINeR) system that utilizes time-division multiplexing of pulse width modulated (PWM) samples. The WINeR-6 Rx consists of four parts: 1) RF front end; 2) signal conditioning; 3) analog output (AO); and 4) field-programmable gate array (FPGA) back end. The RF front end receives RF-modulated neural signals in the 403–490 MHz band with a wide bandwidth of 18 MHz. The frequency-shift keying (FSK) PWM demodulator in the FPGA is a time-to-digital converter with 304 ps resolution, which converts the analog pulse width information to 16-bit digital samples. Automated frequency tracking has been implemented in the Rx to lock onto the free-running voltage-controlled oscillator in the transmitter (Tx). Two antennas and two parallel RF paths are used to increase the wireless coverage area. BCI-2000 graphical user interface has been adopted and modified to acquire, visualize, and record the recovered neural signals in real time. The AO module picks three demultiplexed channels and converts them into analog signals for direct observation on an oscilloscope. One of these signals is further amplified to generate an audio output, offering users the ability to listen to ongoing neural activity. Bench-top testing of the Rx performance with a 32-channel WINeR-6 Tx showed that the input referred noise of the entire system at a Tx–Rx distance of 1.5 m was 4.58 μVrms with 8-bit resolution at 640 kSps. In an in vivo experiment, location-specific receptive fields of hippocampal place cells were mapped during a behavioral experiment in which a rat completed 40 laps in a large circular track. Results were compared against those acquired from the same animal and the same set of electrodes by a commercial hardwired recording system to validate the wirelessly recorded signals. PMID:23428612

  8. A wideband dual-antenna receiver for wireless recording from animals behaving in large arenas.

    PubMed

    Lee, Seung Bae; Yin, Ming; Manns, Joseph R; Ghovanloo, Maysam

    2013-07-01

    A low-noise wideband receiver (Rx) is presented for a multichannel wireless implantable neural recording (WINeR) system that utilizes time-division multiplexing of pulse width modulated (PWM) samples. The WINeR-6 Rx consists of four parts: 1) RF front end; 2) signal conditioning; 3) analog output (AO); and 4) field-programmable gate array (FPGA) back end. The RF front end receives RF-modulated neural signals in the 403-490 MHz band with a wide bandwidth of 18 MHz. The frequency-shift keying (FSK) PWM demodulator in the FPGA is a time-to-digital converter with 304 ps resolution, which converts the analog pulse width information to 16-bit digital samples. Automated frequency tracking has been implemented in the Rx to lock onto the free-running voltage-controlled oscillator in the transmitter (Tx). Two antennas and two parallel RF paths are used to increase the wireless coverage area. BCI-2000 graphical user interface has been adopted and modified to acquire, visualize, and record the recovered neural signals in real time. The AO module picks three demultiplexed channels and converts them into analog signals for direct observation on an oscilloscope. One of these signals is further amplified to generate an audio output, offering users the ability to listen to ongoing neural activity. Bench-top testing of the Rx performance with a 32-channel WINeR-6 Tx showed that the input referred noise of the entire system at a Tx-Rx distance of 1.5 m was 4.58 μV rms with 8-bit resolution at 640 kSps. In an in vivo experiment, location-specific receptive fields of hippocampal place cells were mapped during a behavioral experiment in which a rat completed 40 laps in a large circular track. Results were compared against those acquired from the same animal and the same set of electrodes by a commercial hardwired recording system to validate the wirelessly recorded signals.

  9. Simple nonlinearity evaluation and modeling of low-noise amplifiers with application to radio astronomy receivers.

    PubMed

    Casas, F J; Pascual, J P; de la Fuente, M L; Artal, E; Portilla, J

    2010-07-01

    This paper describes a comparative nonlinear analysis of low-noise amplifiers (LNAs) under different stimuli for use in astronomical applications. Wide-band Gaussian-noise input signals, together with the high values of gain required, make that figures of merit, such as the 1 dB compression (1 dBc) point of amplifiers, become crucial in the design process of radiometric receivers in order to guarantee the linearity in their nominal operation. The typical method to obtain the 1 dBc point is by using single-tone excitation signals to get the nonlinear amplitude to amplitude (AM-AM) characteristic but, as will be shown in the paper, in radiometers, the nature of the wide-band Gaussian-noise excitation signals makes the amplifiers present higher nonlinearity than when using single tone excitation signals. Therefore, in order to analyze the suitability of the LNA's nominal operation, the 1 dBc point has to be obtained, but using realistic excitation signals. In this work, an analytical study of compression effects in amplifiers due to excitation signals composed of several tones is reported. Moreover, LNA nonlinear characteristics, as AM-AM, total distortion, and power to distortion ratio, have been obtained by simulation and measurement with wide-band Gaussian-noise excitation signals. This kind of signal can be considered as a limit case of a multitone signal, when the number of tones is very high. The work is illustrated by means of the extraction of realistic nonlinear characteristics, through simulation and measurement, of a 31 GHz back-end module LNA used in the radiometer of the QUIJOTE (Q U I JOint TEnerife) CMB experiment.

  10. Modulation of VLF signal amplitudes from 5 different transmitters during a C9.3-class solar flare as observed from a single receiving station in India: modeling with an ion chemistry model and LWPC

    NASA Astrophysics Data System (ADS)

    Palit, Sourav; Chakrabarti, Sandip Kumar; Pal, Sujay; Das, Bakul; Ray, Suman

    2016-07-01

    Very Low Frequency (VLF) signal at any location on Earth's surface is strongly dependent on the interference of various modes. The modulation effects on VLF signal due to any terrestrial or extra-terrestrial events vary widely from one propagation path to another depending on the interference patterns along these paths. The task of predicting or reproducing the modulation in the values of signal amplitudes or phase between any two transmitting and receiving stations is challenging. In this work we present results of modeling of the VLF signal amplitudes from five different transmitters as observed at a single receiving station in India during a C9.3 class solar flare. In this model we simulate the ionization rates at lower ionospheric heights from actual flare spectra with the GEANT4 Monte Carlo simulation code and find the equilibrium ion densities with a D-region ion-chemistry model. We find the signal amplitude variation along different propagation paths with the LWPC code. Such efforts are essential for an appropriate understanding of the VLF propagation in Earth's ionosphere waveguide and to achieve desired accuracy while using Earth's ionosphere as an efficient detector of such extra-terrestrial ionization events.

  11. Radiation receiver

    DOEpatents

    Hunt, A.J.

    1983-09-13

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles. 5 figs.

  12. Radiation receiver

    DOEpatents

    Hunt, Arlon J.

    1983-01-01

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

  13. Quality of Life and Survival Outcome for Patients With Nasopharyngeal Carcinoma Receiving Three-Dimensional Conformal Radiotherapy vs. Intensity-Modulated Radiotherapy-A Longitudinal Study

    SciTech Connect

    Fang, F.-M. Chien, C.-Y.; Tsai, W.-L.; Chen, H.-C.; Hsu, H.-C.; Lui, C.-C.; Huang, T.-L.

    2008-10-01

    Purpose: To investigate the changes of quality of life (QoL) and survival outcomes for patients with nasopharyngeal carcinoma (NPC) treated by three-dimensional conformal radiotherapy (3D-CRT) vs. intensity-modulated radiotherapy (IMRT). Methods and Materials: Two hundred and three newly diagnosed NPC patients, who were curatively treated by 3D-CRT (n = 93) or IMRT (n = 110) between March 2002 and July 2004, were analyzed. The distributions of clinical stage according to American Joint Committee on Cancer 1997 were I: 15 (7.4%), II: 78 (38.4%), III: 74 (36.5%), and IV: 36 (17.7%). QoL was longitudinally assessed by the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and the EORTC QLQ-H and N35 questionnaires at the five time points: before RT, during RT (36 Gy), and 3 months, 12 months, and 24 months after RT. Results: The 3-year locoregional control, metastasis-free survival, and overall survival rates were 84.8%, 76.7%, and 81.7% for the 3D-CRT group, respectively, compared with 84.2%, 82.6%, and 85.4% for the IMRT group (p value > 0.05). A general trend of maximal deterioration in most QoL scales was observed during RT, followed by a gradual recovery thereafter. There was no significant difference in most scales between the two groups at each time point. The exception was that patients treated by IMRT had a both statistically and clinically significant improvement in global QoL, fatigue, taste/smell, dry mouth, and feeling ill at the time point of 3 months after RT. Conclusions: The potential advantage of IMRT over 3D-CRT in treating NPC patients might occur in QoL outcome during the recovery phase of acute toxicity.

  14. Intensity-Modulated Radiotherapy Might Increase Pneumonitis Risk Relative to Three-Dimensional Conformal Radiotherapy in Patients Receiving Combined Chemotherapy and Radiotherapy: A Modeling Study of Dose Dumping

    SciTech Connect

    Vogelius, Ivan S.; Westerly, David C.; Cannon, George M.; Mackie, Thomas R.; Mehta, Minesh P.; Sugie, Chikao; Bentzen, Soren M.

    2011-07-01

    Purpose: To model the possible interaction between cytotoxic chemotherapy and the radiation dose distribution with respect to the risk of radiation pneumonitis. Methods and Materials: A total of 18 non-small-cell lung cancer patients previously treated with helical tomotherapy at the University of Wisconsin were selected for the present modeling study. Three treatment plans were considered: the delivered tomotherapy plans; a three-dimensional conformal radiotherapy (3D-CRT) plan; and a fixed-field intensity-modulated radiotherapy (IMRT) plan. The IMRT and 3D-CRT plans were generated specifically for the present study. The plans were optimized without adjusting for the chemotherapy effect. The effect of chemotherapy was modeled as an independent cell killing process by considering a uniform chemotherapy equivalent radiation dose added to all voxels of the organ at risk. The risk of radiation pneumonitis was estimated for all plans using the Lyman and the critical volume models. Results: For radiotherapy alone, the critical volume model predicts that the two IMRT plans are associated with a lower risk of radiation pneumonitis than the 3D-CRT plan. However, when the chemotherapy equivalent radiation dose exceeds a certain threshold, the radiation pneumonitis risk after IMRT is greater than after 3D-CRT. This threshold dose is in the range estimated from clinical chemoradiotherapy data sets. Conclusions: Cytotoxic chemotherapy might affect the relative merit of competing radiotherapy plans. More work is needed to improve our understanding of the interaction between chemotherapy and the radiation dose distribution in clinical settings.

  15. Prognostic Correlations between ABO Blood Group and Pre-Treatment Plasma Epstein-Barr Virus DNA in Patients with Nasopharyngeal Carcinoma Receiving Intensity-Modulated Radiotherapy

    PubMed Central

    Li, Wen-Fei; Zhang, Yuan; Liu, Li-Zhi; Tian, Li; Lin, Ai-Hua; Sun, Ying; Ma, Jun

    2016-01-01

    Purpose The objective of this study is to assess the prognostic value of ABO blood group in nasopharyngeal carcinoma (NPC) treated by intensity-modulated radiotherapy (IMRT). Patients and Methods We retrospectively reviewed the data on 1397 patients with non-metastatic, newly diagnosed NPC treated using IMRT. Patient survival between different ABO blood groups were compared using log-rank test. Cox hazards model was adopted to establish independent prognostic factors. Results In our study, the distribution of the A, B, AB and O blood groups was 26.6% (372/1397), 26.2% (366/1397), 5.2% (73/1397) and 42.0% (586/1397), respectively. The cut-off value of pre-treatment Epstein-Barr virus (EBV) DNA based on disease-free survival (DFS) was 1355 copies/ml (area under curve [AUC], 0.649; sensitivity, 0.76; specificity, 0.496) for the whole cohort. Estimated four-year DFS, overall survival (OS), distant metastasis-free survival (DMFS) and locoregional relapse-free survival (LRRFS) rates were 81.7%, 89.2%, 89.4% and 92.3% for blood group A; 82.1%, 89.3%, 89.0% and 92.0% for group B; 83.3%, 88.1%, 86.2% and 95.5% for group AB, 80.9%, 90.7%, 88.4% and 90.2% for group O (P > 0.05 for all rates). Multivariate analysis revealed ABO blood group was not an independent prognostic factor for DFS, OS, DMFS or LRRFS (P > 0.05 for all rates) after adjusting for plasma EBV DNA in either the whole cohort or subgroup analysis by gender. Conclusions The prognostic value of ABO blood group may be limited for patients with NPC in the era of IMRT, and no substantial correlation between ABO blood group and plasma EBV DNA was observed. PMID:27835689

  16. Investigation of long-term survival outcomes and failure patterns of patients with nasopharyngeal carcinoma receiving intensity-modulated radiotherapy: a retrospective analysis

    PubMed Central

    Zhao, Wei; Lei, Hao; Zhu, Xiaodong; Li, Ling; Qu, Song; Liang, Xia

    2016-01-01

    Intensity-modulated radiotherapy (IMRT) has replaced the conventional radiotherapy (2D-RT) and improved clinical efficacy in Nasopharyngeal Carcinoma (NPC) patients. In the present study, we retrospectively analyzed the clinical characteristics of patients with NPC treated with IMRT to assess the long-term survival outcomes and failure patterns. Of the 527 patients, One hundred and twenty-one patients experienced treatment failure, 86 patients developed distant metastases, and 12 patients developed a second primary tumor. The local and regional recurrence rates were 31.4% and 14.0%, respectively. The 5-year overall survival (OS), progression-free survival (PFS), local recurrence-free survival (LRFS), regional relapse-free survival (RRFS), and distant metastatic relapse-free survival (DMFS) rates were 80.9%, 75.6%, 91.7%, 96.2%, and 83.0%, respectively. The 5-year LRFS rates of Stage T1-4 patients were 100.0%, 93.1%, 92.0%, and 85.8%, respectively. The 5-year DMFS rates of Stage N0-3 patients were 95.0%, 86.1%, 79.5%, and 67.2%, respectively. Multivariate analysis showed age and T-stage were independent predictors of OS, T-stage was an independent predictor of LRFS, and age and N-stage were independent predictors of PFS and DMFS. In summary, the improved treatment results with IMRT are primarily due to the achievement of a higher local tumor control rate and OS in NPC patients. However, distant metastasis was the most commonly observed failure pattern after treatment. These results provide deep insights about the value of IMRT in the treatment and prognosis of NPC patients. PMID:27894100

  17. Performance of OOK and low-order PPM modulations in optical communications when using APD-based receivers. [Off-On Keying and Pulse Position Modulation using Avalanche PhotoDiodes

    NASA Technical Reports Server (NTRS)

    Abshire, J. B.

    1984-01-01

    The paper computes direct detection laser communications receiver performance when using avalanche photodiode (APD) detectors. The performances are compared in terms of bit error probability vs average signal required per bit when the transmitter uses either on-off keying (OOK) or low-order PPM formats. It is shown that QPPM requires 3 dB less signal than OOK, while BPPM requires the same or slightly more than OOK for the same performance. Optimum APD gain values range from 200 to 400. When using QPPM, k(eff) = 0.006, and optimum gain, 60 signal counts/bit are required at 500 Mbits/s for a 0.000001 bit error probability. It is concluded that QPPM may be an attractive signaling format for some fiber or free space laser communication applications.

  18. Digital Monopulse Receivers for Phase Modulated Signals

    DTIC Science & Technology

    2005-04-14

    comunicaciones ación... e Madrid s/n...θ1k Σ+j∆ ∆ digital Σ digital Signal formation ∆ digit Σ digit ∆ digit Σ digitRCHITECTURES BASED ON AMPLITUDE MEASUREMENT e architectures perform the

  19. RFID receiver apparatus and method

    DOEpatents

    Scott, Jeffrey Wayne

    2006-12-26

    An RFID backscatter interrogator for transmitting data to an RFID tag, generating a carrier for the tag, and receiving data from the tag modulated onto the carrier, the interrogator including a single grounded-coplanar wave-guide circuit board and at least one surface mount integrated circuit supported by the circuit board.

  20. Development of an Air Brayton solar receiver

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Various receiver configurations and operating conditions were examined. The interface requirements between the receiver/concentrator/power module were addressed. Production cost estimates were obtained to determine the cost of the receiver during the 1980 timeframe. A conceptual design of an air Brayton solar receiver is presented based on the results. The following design goals were established: (1)peak thermal input power - 85 KWt; (2)receiver outlet air temperature - 1500 F; (3)receiver inlet air temperature - 1050 F; (4)design mass flow rate - 0.533 lb/sec; and (5)design receiver inlet pressure - 36.75 psia.

  1. Giving and Receiving Feedback. Pre-Apprenticeship Phase 1 Training.

    ERIC Educational Resources Information Center

    Lane Community Coll., Eugene, OR.

    One of a series of pre-apprenticeship training modules, this self-paced student training module deals with giving and receiving feedback. Included in the module are the following: cover sheet listing module title, goals, and performance indicators; introduction; study guide/check list with directions for module completion; information sheet…

  2. Flexible receiver accurately tracks multiple threats

    NASA Astrophysics Data System (ADS)

    Browne, Jack

    1988-09-01

    The design and performance of a broadband (0.03-40-GHz) receiver system for electronic-surveillance applications are described. The complete superheterodyne receiver system comprises a control and display unit, a scan display, an equipment frame, and a choice of readily interchangeable RF tuner and demodulator modules with narrow or broad instantaneous bandwidths and BITE capability. Photographs, block diagrams, and tables listing the performance parameters of the modules are provided.

  3. Future GOES-R global ground receivers

    NASA Astrophysics Data System (ADS)

    Dafesh, P. A.; Grayver, E.

    2006-08-01

    The Aerospace Corporation has developed an end-to-end testbed to demonstrate a wide range of modern modulation and coding alternatives for future broadcast by the GOES-R Global Rebroadcast (GRB) system. In particular, this paper describes the development of a compact, low cost, flexible GRB digital receiver that was designed, implemented, fabricated, and tested as part of the development. This receiver demonstrates a 10-fold increase in data rate compared to the rate achievable by the current GOES generation, without a major impact on either cost or size. The digital receiver is integrated on a single PCI card with an FPGA device, and analog-to-digital converters. It supports a wide range of modulations (including 8-PSK and 16-QAM) and turbo coding. With appropriate FPGA firmware and software changes, it can also be configured to receive the current (legacy) GOES signals. The receiver has been validated by sending large image files over a high-fidelity satellite channel emulator, including a space-qualified power amplifier and a white noise source. The receiver is a key component of a future GOES-R weather receiver system (also called user terminal) that includes the antenna, low-noise amplifier, downconverter, filters, digital receiver, and receiver system software. This work describes this receiver proof of concept and its application to providing a very credible estimate of the impact of using modern modulation and coding techniques in the future GOES-R system.

  4. Back-end Science Model Integration for Ecological Risk Assessment

    EPA Science Inventory

    The U.S. Environmental Protection Agency (USEPA) relies on a number of ecological risk assessment models that have been developed over 30-plus years of regulating pesticide exposure and risks under Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Endangered Spe...

  5. Back-end Science Model Integration for Ecological Risk Assessment.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (USEPA) relies on a number of ecological risk assessment models that have been developed over 30-plus years of regulating pesticide exposure and risks under Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Endangered Spe...

  6. 40 CFR 63.493 - Back-end process provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... §§ 63.494 through 63.500. Owners and operators of affected sources whose only elastomer products are... an affected source that also produces another elastomer product, the provisions of §§ 63.494...

  7. 40 CFR 63.493 - Back-end process provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... §§ 63.494 through 63.500. Owners and operators of affected sources whose only elastomer products are... an affected source that also produces another elastomer product, the provisions of §§ 63.494...

  8. 40 CFR 63.493 - Back-end process provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... §§ 63.494 through 63.500. Owners and operators of affected sources whose only elastomer products are... an affected source that also produces another elastomer product, the provisions of §§ 63.494...

  9. 40 CFR 63.493 - Back-end process provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... §§ 63.494 through 63.500. Owners and operators of affected sources whose only elastomer products are... an affected source that also produces another elastomer product, the provisions of §§ 63.494...

  10. Visualization for Hyper-Heuristics: Back-End Processing

    SciTech Connect

    Simon, Luke

    2015-03-01

    Modern society is faced with increasingly complex problems, many of which can be formulated as generate-and-test optimization problems. Yet, general-purpose optimization algorithms may sometimes require too much computational time. In these instances, hyperheuristics may be used. Hyper-heuristics automate the design of algorithms to create a custom algorithm for a particular scenario, finding the solution significantly faster than its predecessor. However, it may be difficult to understand exactly how a design was derived and why it should be trusted. This project aims to address these issues by creating an easy-to-use graphical user interface (GUI) for hyper-heuristics and an easy-to-understand scientific visualization for the produced solutions. To support the development of this GUI, my portion of the research involved developing algorithms that would allow for parsing of the data produced by the hyper-heuristics. This data would then be sent to the front-end, where it would be displayed to the end user.

  11. Solar dynamic heat receiver technology

    NASA Technical Reports Server (NTRS)

    Sedgwick, Leigh M.

    1991-01-01

    A full-size, solar dynamic heat receiver was designed to meet the requirements specified for electrical power modules on the U.S. Space Station, Freedom. The heat receiver supplies thermal energy to power a heat engine in a closed Brayton cycle using a mixture of helium-xenon gas as the working fluid. The electrical power output of the engine, 25 kW, requires a 100 kW thermal input throughout a 90 minute orbit, including when the spacecraft is eclipsed for up to 36 minutes from the sun. The heat receiver employs an integral thermal energy storage system utilizing the latent heat available through the phase change of a high-temperature salt mixture. A near eutectic mixture of lithium fluoride and calcium difluoride is used as the phase change material. The salt is contained within a felt metal matrix which enhances heat transfer and controls the salt void distribution during solidification. Fabrication of the receiver is complete and it was delivered to NASA for verification testing in a simulated low-Earth-orbit environment. This document reviews the receiver design and describes its fabrication history. The major elements required to operate the receiver during testing are also described.

  12. Putting the "receive" in accounts receivable.

    PubMed

    McDaniel, John W; Baum, Neil

    2006-01-01

    There isn't a practice in the United States that doesn't have a concern about accounts receivable. The financial success of any practice depends on the care and feeding of the accounts receivable. This is not an area of practice management that can be taken lightly or delegated to someone who is not attentive to detail and doggedly persistent. In this article, we will discuss how to identify problematic accounts receivable and what can be done to bring the accounts receivable under control. We will provide you with a plan of action that can be adopted by any practice regardless of size, number of physicians, or whether the practice uses in-house billing or outsources its billing arrangements.

  13. PPM Receiver Implemented in Software

    NASA Technical Reports Server (NTRS)

    Gray, Andrew; Kang, Edward; Lay, Norman; Vilnrotter, Victor; Srinivasan, Meera; Lee, Clement

    2010-01-01

    A computer program has been written as a tool for developing optical pulse-position- modulation (PPM) receivers in which photodetector outputs are fed to analog-to-digital converters (ADCs) and all subsequent signal processing is performed digitally. The program can be used, for example, to simulate an all-digital version of the PPM receiver described in Parallel Processing of Broad-Band PPM Signals (NPO-40711), which appears elsewhere in this issue of NASA Tech Briefs. The program can also be translated into a design for digital PPM receiver hardware. The most notable innovation embodied in the software and the underlying PPM-reception concept is a digital processing subsystem that performs synchronization of PPM time slots, even though the digital processing is, itself, asynchronous in the sense that no attempt is made to synchronize it with the incoming optical signal a priori and there is no feedback to analog signal processing subsystems or ADCs. Functions performed by the software receiver include time-slot synchronization, symbol synchronization, coding preprocessing, and diagnostic functions. The program is written in the MATLAB and Simulink software system. The software receiver is highly parameterized and, hence, programmable: for example, slot- and symbol-synchronization filters have programmable bandwidths.

  14. Wideband infrared receiver backend. [Doppler radar, radiometers

    NASA Technical Reports Server (NTRS)

    Flattau, T.; Mellars, J.

    1974-01-01

    The design, operation, and configuration of the receiver backend for a wideband infrared tracking receiver are described. A squaring loop is incorporated into the receiver design to enable it to track the Doppler shifted carrier which is Phase Shift Keyed modulated. The receiver has a 400 MHz instantaneous bandwidth and tracks signals whose carrier frequency at the backend input is between 200 and 900 MHz with frequency variation rates greater than 20 MHz/second. The output data is compatible with MECL 3 logic.

  15. Solar heat receiver

    DOEpatents

    Hunt, A.J.; Hansen, L.J.; Evans, D.B.

    1982-09-29

    A receiver is described for converting solar energy to heat a gas to temperatures from 700 to 900/sup 0/C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  16. Solar heat receiver

    DOEpatents

    Hunt, Arlon J.; Hansen, Leif J.; Evans, David B.

    1985-01-01

    A receiver for converting solar energy to heat a gas to temperatures from 700.degree.-900.degree. C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  17. Final Technical Progress Report: High-Efficiency Low-Cost Thin-Film GaAs Photovoltaic Module Development Program; July 14, 2010 - January 13, 2012

    SciTech Connect

    Mattos, L.

    2012-03-01

    This is the final technical progress report of the High-Efficiency Low-Cost Thin-Film GaAs Photovoltaic Module Development Program. Alta Devices has successfully completed all milestones and deliverables established as part of the NREL PV incubator program. During the 18 months of this program, Alta has proven all key processes required to commercialize its solar module product. The incubator focus was on back end process steps directed at conversion of Alta's high quality solar film into high efficiency 1-sun PV modules. This report describes all program deliverables and the work behind each accomplishment.

  18. Integrated Microphotonic Receiver for Ka-Band

    NASA Technical Reports Server (NTRS)

    Levi, A. F. J.

    2005-01-01

    This report consists of four main sections. Part I: LiNbO3 microdisk resonant optical modulator. Brief review of microdisk optical resonator and RF ring resonator. Microwave and photonic design challenges for achieving simultaneous RF-optical resonance are addressed followed by our solutions. Part II: Experimental demonstration of LiNbO3 microdisk modulator performance in wired and wireless RF-optical links. Part III: Microphotonic RF receiver architecture that exploits the nonlinear modulation in the LiNbO3 microdisk modulator to achieve direct photonic down-conversion from RF carrier without using any high-speed electronic elements. Part IV: Ultimate sensitivity of the microdisk photonic receiver and the future road map toward a practical device.

  19. Solar energy modulator

    NASA Technical Reports Server (NTRS)

    Hale, R. R. (Inventor); Mcdougal, A. R.

    1984-01-01

    A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror, therby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening.

  20. Probability of Intercept in Electronic Countermeasures Receivers

    DTIC Science & Technology

    1975-12-01

    modulating signals A and B are input to the 𔃻WT helix caus.ing a single frequency on the helix of TWT #1 to produce phase modu- lation of frequency A...and harmonics of A in TWT #1. A single frequency on the helix of TVT 42 produces phase modulation of frequency B and harmonics of B in TWT #2. The high...with YIG Pres’Žlector 34 9 Superheterodyne Receiver YIG z iter TWT 36 10 Wideband crystal video receiver 38 11 Tangential Sensitivity 40 12 Sensitivity

  1. Digital Signal Processing Based Biotelemetry Receivers

    NASA Technical Reports Server (NTRS)

    Singh, Avtar; Hines, John; Somps, Chris

    1997-01-01

    This is an attempt to develop a biotelemetry receiver using digital signal processing technology and techniques. The receiver developed in this work is based on recovering signals that have been encoded using either Pulse Position Modulation (PPM) or Pulse Code Modulation (PCM) technique. A prototype has been developed using state-of-the-art digital signal processing technology. A Printed Circuit Board (PCB) is being developed based on the technique and technology described here. This board is intended to be used in the UCSF Fetal Monitoring system developed at NASA. The board is capable of handling a variety of PPM and PCM signals encoding signals such as ECG, temperature, and pressure. A signal processing program has also been developed to analyze the received ECG signal to determine heart rate. This system provides a base for using digital signal processing in biotelemetry receivers and other similar applications.

  2. Hybrid receiver study

    NASA Technical Reports Server (NTRS)

    Stone, M. S.; Mcadam, P. L.; Saunders, O. W.

    1977-01-01

    The results are presented of a 4 month study to design a hybrid analog/digital receiver for outer planet mission probe communication links. The scope of this study includes functional design of the receiver; comparisons between analog and digital processing; hardware tradeoffs for key components including frequency generators, A/D converters, and digital processors; development and simulation of the processing algorithms for acquisition, tracking, and demodulation; and detailed design of the receiver in order to determine its size, weight, power, reliability, and radiation hardness. In addition, an evaluation was made of the receiver's capabilities to perform accurate measurement of signal strength and frequency for radio science missions.

  3. Hybrid lidar radar receiver for underwater imaging applications

    NASA Astrophysics Data System (ADS)

    Seetamraju, Madhavi; Gurjar, Rajan; Squillante, Michael; Derderian, Jeffrey P.

    2009-05-01

    In this work, we present research performed to improve the receiver characteristics for underwater imaging applications using the hybrid lidar-radar detection technique. We report the development of the next-generation coherent heterodyne receiver using modulation of the optical receiver's amplifier gain. Significant advantages in the receiver specifications are achieved using a large-area, high gain, low-noise silicon avalanche photodiode (APD) as the photodetector cum frequency mixer-demodulator. We demonstrate that heterodyne detection by gain modulation of APD can be used to increase the signal-to-noise ratio, detection sensitivity and bandwidth for the hybrid receiver system.

  4. 30-micron heterodyne receiver

    NASA Technical Reports Server (NTRS)

    Kostiuk, Theodor; Spears, David L.

    1987-01-01

    Advantages and constraints of remote measurements using heterodyne spectroscopy near 30 microns are discussed. The state of the art of wideband HgCdTe photomixers and PbSnSe diode-laser local oscillators being developed for FIR heterodyne receivers is described. The first compact 30-micron heterodyne radiometer was built, and initial results at 28-microns show about 2-percent mixer efficiency for a 500-MHz-bandwidth receiver. Factors limiting receiver performance are discussed, along with the projected sensitivity of new interdigitated-electrode HgCdTe photoconductor mixers being developed for operation up to 200 microns.

  5. Ultrasonic pulser-receiver

    DOEpatents

    Taylor, Steven C.

    2006-09-12

    Ultrasonic pulser-receiver circuitry, for use with an ultrasonic transducer, the circuitry comprising a circuit board; ultrasonic pulser circuitry supported by the circuit board and configured to be coupled to an ultrasonic transducer and to cause the ultrasonic transducer to emit an ultrasonic output pulse; receiver circuitry supported by the circuit board, coupled to the pulser circuitry, including protection circuitry configured to protect against the ultrasonic pulse and including amplifier circuitry configured to amplify an echo, received back by the transducer, of the output pulse; and a connector configured to couple the ultrasonic transducer directly to the circuit board, to the pulser circuitry and receiver circuitry, wherein impedance mismatches that would result if the transducer was coupled to the circuit board via a cable can be avoided.

  6. Solar energy receiver

    DOEpatents

    Schwartz, Jacob

    1978-01-01

    An improved long-life design for solar energy receivers provides for greatly reduced thermally induced stress and permits the utilization of less expensive heat exchanger materials while maintaining receiver efficiencies in excess of 85% without undue expenditure of energy to circulate the working fluid. In one embodiment, the flow index for the receiver is first set as close as practical to a value such that the Graetz number yields the optimal heat transfer coefficient per unit of pumping energy, in this case, 6. The convective index for the receiver is then set as closely as practical to two times the flow index so as to obtain optimal efficiency per unit mass of material.

  7. Project Echo: Receiving System

    NASA Technical Reports Server (NTRS)

    Ohm, E. A.

    1961-01-01

    A tracking horn-reflector antenna, a maser preamplifier (and standby parametric preamplifier), and a special FM demodulator were combined to form a low-noise receiving system which made possible the establishment of a high-quality voice circuit via the Echo I passive satellite. This paper describes the 2390-Mc receiving system located at the Bell Telephone Laboratories facility in Holmdel, New Jersey.

  8. Advanced Solar Receivers

    NASA Technical Reports Server (NTRS)

    Owen, W. A.

    1984-01-01

    Low thermal efficiencies in solar receivers are discussed in terms of system design. It is recommended that careful attention be given to the overall thermal systems design, especially to conductive losses about the window and areas of relatively thin insulation. If the cavity design is carefully managed to insure a small, minimally reradiating aperture, the goal of a very high efficiency cavity receiver is a realistic one.

  9. OCD RADIO ALERT RECEIVERS.

    DTIC Science & Technology

    for methods of operating a radioalert system were established in conjunction with OCD representatives. Four types of operation were selected. Three...models each of these four receiver types were fabricated and tested. The total of 12 laboratory models were delivered to OCD . Test equipment...suitable for demonstrating the two most promising receiver types was also assembled, and delivered to OCD . A preliminary analysis of the cost of mass

  10. SRT as a receiver in a bistatic radar space debris configuration

    NASA Astrophysics Data System (ADS)

    Pisanu, T.; Concu, R.; Gaudiomonte, F.; Marongiu, P.; Melis, A.; Serra, G.; Urru, E.; Valente, G.; Portelli, C.; Muntoni, G.; Bianchi, G.; Comoretto, G.; Dolce, F.; Paoli, J.; Reali, M.; Villadei, W.

    2016-08-01

    Space debris is becoming a very important and urgent problem for present and future space activities. For that reason many public and private Institutions in the world are being involved in order to monitor and control the debris population increase and to understand which facilities can be used for improving the surveillance and tracking capabilities. In this framework in 2014 we performed some preliminary observations in a beam parking, CW mode and a bistatic configuration, with a transmitter of 4 kW of the Italian Air Force and the SRT (Sardinia Radio Telescope) a 64 meters radiotelescope used as a receiver. We performed the observations in P band at 410 MHz, receiving the signal diffused from some debris of different sizes and distances in LEO orbit, in order to understand the performances and capabilities of the system. In this article we will describe the results of this observations campaign, the simulation work done for preparing it, the RCS (radar cross section) observed, the level of the received signals, the Doppler measurements, and the work we are doing for developing a new and higher performing digital back end, able to process the data received.

  11. Central solar energy receiver

    DOEpatents

    Drost, M. Kevin

    1983-01-01

    An improved tower-mounted central solar energy receiver for heating air drawn through the receiver by an induced draft fan. A number of vertically oriented, energy absorbing, fin-shaped slats are radially arranged in a number of concentric cylindrical arrays on top of the tower coaxially surrounding a pipe having air holes through which the fan draws air which is heated by the slats which receive the solar radiation from a heliostat field. A number of vertically oriented and wedge-shaped columns are radially arranged in a number of concentric cylindrical clusters surrounding the slat arrays. The columns have two mirror-reflecting sides to reflect radiation into the slat arrays and one energy absorbing side to reduce reradiation and reflection from the slat arrays.

  12. Olympus beacon receiver

    NASA Technical Reports Server (NTRS)

    Ostergaard, Jens

    1988-01-01

    A medium-size Beacon Receiving System for reception and processing of the B1 (20 GHz) and B2 (30 GHz) beacons from Olympus has been developed. Integration of B1 and B2 receiving equipment into one system using one antenna and a common computer for control and data processing provides the advantages of a compact configuration and synchronization of the two receiver chains. Range for co-polar signal attenuation meaurement is about 30 dB for both beacons, increasing to 40 dB for B2 if the receivers are synchronized to B1. The accuracy is better than 0.5 dB. Cross-polarization discriminations of the order of 10 to 30 dB may be determined with an accuracy of 1 to 2 dB. A number of radiometers for complementary measurements of atmospheric attenuation of 13 to 30 GHz has also been constructed. A small multi-frequency system for operation around 22 GHz and 31 GHz is presently under development.

  13. Received Pronunciation and "Realphonetik."

    ERIC Educational Resources Information Center

    Shibles, Warren

    1995-01-01

    This article argues that British Received Pronunciation (RP) is inconsistently defined, arbitrary, and anachronistic, and that it should be replaced as an instructional concept by British Pronunciation (BP), which would be based on an actual and adequate descriptive phonetics, called here "Realphonetik." Contains 77 references. (MDM)

  14. Help Seeking and Receiving.

    ERIC Educational Resources Information Center

    Nadler, Arie

    Although social psychology has always had an interest in helping behavior, only recently has the full complexity of helping relations begun to be researched. Help seeking and receiving in the educational setting raise many issues regarding the use and effectiveness of the help itself. Central to all helping relations is the seeking/receiving…

  15. Submillimeter wave heterodyne receiver

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Goutam (Inventor); Manohara, Harish (Inventor); Siegel, Peter H. (Inventor); Ward, John (Inventor)

    2011-01-01

    In an embodiment, a submillimeter wave heterodyne receiver includes a finline ortho-mode transducer comprising thin tapered metallic fins deposited on a thin dielectric substrate to separate a vertically polarized electromagnetic mode from a horizontally polarized electromagnetic mode. Other embodiments are described and claimed.

  16. Zero-power receiver

    DOEpatents

    Brocato, Robert W.

    2016-10-04

    An unpowered signal receiver and a method for signal reception detects and responds to very weak signals using pyroelectric devices as impedance transformers and/or demodulators. In some embodiments, surface acoustic wave devices (SAW) are also used. Illustrative embodiments include satellite and long distance terrestrial communications applications.

  17. Hanson receives Macelwane Medal

    NASA Astrophysics Data System (ADS)

    Ravishankara, A. R.; Hanson, David R.

    At the 1996 Spring Meeting in Baltimore, Maryland, David R. Hanson received the 1996 James B. Macelwane Medal, which recognizes significant contributions to the geophysical sciences by a young scientist of outstanding ability. The medal citation and Hanson's response are given here.

  18. A C-Band satellite receiver

    NASA Astrophysics Data System (ADS)

    Lupinetti, F.; Ingels, F.

    1985-12-01

    The design concept of a 24-channel C-band receiver for satellite TV signals is presented. The system comprises a low-noise amplifier, a 3.7-4.2-GHz/450-910-MHz block down converter, the receiver proper (a modified analog UNF tuner at IF = 45 MHz and a digital channel selector), and an RF modulator providing video and audio on channels 3 or 4. The operation of the receiver is described and illustrated with block diagrams and tables of specifications. A prototype receiver has been found to give good video quality and definition with clear 20-20,000-Hz audio when used with a 4-ft dish antenna.

  19. Polarization Independent Electro-Optic Modulator

    NASA Technical Reports Server (NTRS)

    Yao, Xiao-Tian Steve (Inventor)

    1997-01-01

    A polarization insensitive electro-optic modulator is constructed by providing a polarization beamsplitter to separate an incoming light beam into two orthogonally plane polarized beams. Each of the polarized beams passes through a separate electro-optic modulator where each beam is modulated by the same data signal. After modulation the beams are combined to yield a modulated beam having modulated components that are orthogonally polarized. Not only is this device insensitive to changes in polarization of the input beam, the final modulated beam can be detected by optical receivers without regard to polarization alignment of the modulated beam and the receiver.

  20. RRI-GBT Multi-band Receiver: Motivation, Design, and Development

    NASA Astrophysics Data System (ADS)

    Maan, Yogesh; Deshpande, Avinash A.; Chandrashekar, Vinutha; Chennamangalam, Jayanth; Raghavendra Rao, K. B.; Somashekar, R.; Anderson, Gary; Ezhilarasi, M. S.; Sujatha, S.; Kasturi, S.; Sandhya, P.; Bauserman, Jonah; Duraichelvan, R.; Amiri, Shahram; Aswathappa, H. A.; Barve, Indrajit V.; Sarabagopalan, G.; Ananda, H. M.; Beaudet, Carla; Bloss, Marty; Dhamnekar, Deepa B.; Egan, Dennis; Ford, John; Krishnamurthy, S.; Mehta, Nikhil; Minter, Anthony H.; Nagaraja, H. N.; Narayanaswamy, M.; O'Neil, Karen; Raja, Wasim; Sahasrabudhe, Harshad; Shelton, Amy; Srivani, K. S.; Venugopal, H. V.; Viswanathan, Salna T.

    2013-01-01

    We report the design and development of a self-contained multi-band receiver (MBR) system, intended for use with a single large aperture to facilitate sensitive and high time-resolution observations simultaneously in 10 discrete frequency bands sampling a wide spectral span (100-1500 MHz) in a nearly log-periodic fashion. The development of this system was primarily motivated by need for tomographic studies of pulsar polar emission regions. Although the system design is optimized for the primary goal, it is also suited for several other interesting astronomical investigations. The system consists of a dual-polarization multi-band feed (with discrete responses corresponding to the 10 bands pre-selected as relatively radio frequency interference free), a common wide-band radio frequency front-end, and independent back-end receiver chains for the 10 individual sub-bands. The raw voltage time sequences corresponding to 16 MHz bandwidth each for the two linear polarization channels and the 10 bands are recorded at the Nyquist rate simultaneously. We present the preliminary results from the tests and pulsar observations carried out with the Robert C. Byrd Green Bank Telescope using this receiver. The system performance implied by these results and possible improvements are also briefly discussed.

  1. A Study of 358 Cases of Locally Advanced Nasopharyngeal Carcinoma Receiving Intensity-Modulated Radiation Therapy: Improving the Seventh Edition of the American Joint Committee on Cancer T-Staging System

    PubMed Central

    Zhou, Qin; He, Yuxiang; Zhao, Yajie; Wang, Yin; Kuang, Weilu

    2017-01-01

    To evaluate the rationality and limitations of the seventh edition of the American Joint Committee on Cancer (the 7th AJCC edition) T-staging system for locally advanced nasopharyngeal carcinoma (NPC). The prognosis of 358 patients with stage T3/T4 NPC treated with intensity-modulated radiotherapy (IMRT) was analyzed with the Kaplan–Meier method or the log-rank test. The 7th AJCC staging system of NPC has some limitations in that the T category is neither the significant factor in OS/LRFS nor the independent prognostic factor in OS/LRFS/DMFS/DFS (P > 0.05). After adjustment by anatomic structures, univariate analysis has shown that the adjusted-T category has statistical significance between T3 and T4 for OS (86.4% and 71.3%, P = 0.002), LRFS (97% and 90.9%, P = 0.048), DMFS (90.9% and 77.2%, P = 0.001), and DFS (86.2% and 67.5%, P = 0.000), and multivariate analysis has shown that the adjusted-T category is an independent prognostic factor for OS/DMFS/DFS (with the exception of LRFS). Then, GTV-P was taken into consideration. Multivariate analysis showed that these nT categories serve as suitable independent prognostic factors for OS/DMFS/DFS (P < 0.001) and LRFS (HR = 3.131; 95% CI, 1.090–8.990; P = 0.043). The 7th AJCC staging system has limitations and should be improved by including the modifications suggested, such as anatomic structures and tumor volume adjustment. PMID:28265567

  2. Avalanche Photodiode Arrays for Optical Communications Receivers

    NASA Technical Reports Server (NTRS)

    Srinivasan, M.; Vilnrotter, V.

    2001-01-01

    An avalanche photodiode (APD) array for ground-based optical communications receivers is investigated for the reception of optical signals through the turbulent atmosphere. Kolmogorov phase screen simulations are used to generate realistic spatial distributions of the received optical field. It is shown that use of an APD array for pulse-position modulation detection can improve performance by up to 4 dB over single APD detection in the presence of turbulence, but that photon-counting detector arrays yield even greater gains.

  3. A digital beacon receiver

    NASA Technical Reports Server (NTRS)

    Ransome, Peter D.

    1988-01-01

    A digital satellite beacon receiver is described which provides measurement information down to a carrier/noise density ratio approximately 15 dB below that required by a conventional (phase locked loop) design. When the beacon signal fades, accuracy degrades gracefully, and is restored immediately (without hysteresis) on signal recovery, even if the signal has faded into the noise. Benefits of the digital processing approach used include the minimization of operator adjustments, stability of the phase measuring circuits with time, repeatability between units, and compatibility with equipment not specifically designed for propagation measuring. The receiver has been developed for the European Olympus satellite which has continuous wave (CW) beacons at 12.5 and 29.7 GHz, and a switched polarization beacon at 19.8 GHz approximately, but the system can be reconfigured for CW and polarization-switched beacons at other frequencies.

  4. The Themis solar receiver

    NASA Astrophysics Data System (ADS)

    Gravrand, J. M.; Pouget-Abadie, X.

    The theoretical modeling, materials, and design of the central receiver heat exchanger on the tower of the Themis solar power plant are presented. The receiver was conceived based on the incident solar flux at different times of the day and year and the efficiency of transferring the heat to molten salts. The square aperture admits energy at a peak rate of 3.402 MWth at some points, with heat transfer to the power loop resulting in a maximum efficiency of 25 percent. Optimization studies indicated a receiver inclined 30 deg from the horizontal to face the heliostat field, and the flux incident on the walls was mapped. Tubes filled with the salts at 250 C form the walls behind radiator fins and elevate the salt to temperatures up to a limit of 490 C. Measures taken to allow for the expansion of the cavity walls and to mount the heat exchange tubes for easy replacement are described, along with the instrumentation to measure performance, flux, and detect malfunctions due to perturbations in the fluid flow or failure of any of the components.

  5. LANL receiver system development

    SciTech Connect

    Laubscher, B.; Cooke, B.; Cafferty, M.; Olivas, N.

    1997-08-01

    The CALIOPE receiver system development at LANL is the story of two technologies. The first of these technologies consists of off-the-shelf mercury-cadmium-telluride (MCT) detectors and amplifiers. The vendor for this system is Kolmar Technologies. This system was fielded in the Tan Trailer I (TTI) in 1995 and will be referred to in this paper as GEN I. The second system consists of a MCT detector procured from Santa Barbara Research Center (SBRC) and an amplifier designed and built by LANL. This system was fielded in the Tan Trailer II (TTII) system at the NTS tests in 1996 and will be referred to as GEN II. The LANL CALIOPE experimental plan for 1996 was to improve the lidar system by progressing to a higher rep rate laser to perform many shots in a much shorter period of time. In keeping with this plan, the receiver team set a goal of developing a detector system that was background limited for the projected 100 nanosecond (ns) laser pulse. A set of detailed simulations of the DIAL lidar experiment was performed. From these runs, parameters such as optimal detector size, field of view of the receiver system, nominal laser return power, etc. were extracted. With this information, detector physics and amplifier electronic models were developed to obtain the required specifications for each of these components. These derived specs indicated that a substantial improvement over commercially available, off-the-shelf, amplifier and detector technologies would be needed to obtain the goals. To determine if the original GEN I detector was usable, the authors performed tests on a 100 micron square detector at cryogenic temperatures. The results of this test and others convinced them that an advanced detector was required. Eventually, a suitable detector was identified and a number of these single element detectors were procured from SBRC. These single element detectors were witness for the detector arrays built for another DOE project.

  6. Ultra-wideband receiver

    DOEpatents

    McEwan, Thomas E.

    1994-01-01

    An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, .+-.UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals.

  7. Ultra-wideband receiver

    DOEpatents

    McEwan, T.E.

    1994-09-06

    An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, [+-] UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals. 16 figs.

  8. Ultra-wideband receiver

    DOEpatents

    McEwan, Thomas E.

    1996-01-01

    An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, .+-.UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals.

  9. Ultra-wideband receiver

    DOEpatents

    McEwan, T.E.

    1996-06-04

    An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, {+-}UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals. 21 figs.

  10. Custom accounts receivable modeling.

    PubMed

    Veazie, J

    1994-04-01

    In hospital and clinic management, accounts are valued as units and handled equally--a $20 account receives the same minimum number of statements as a $20,000 account. Quite often, the sheer number of accounts a hospital or clinic has to handle forces executives to manage accounts by default and failure--accounts mature on an aging track and, if left unpaid by patients, eventually are sent to collections personnel. Of the bad-debt accounts placed with collections agencies, many are misclassified as charity or hardship cases, while others could be collected by hospital or clinic staff with a limited amount of additional effort.

  11. Optical superheterodyne receiver uses laser for local oscillator

    NASA Technical Reports Server (NTRS)

    Lucy, R. F.

    1966-01-01

    Optical superheterodyne receiver uses a laser coupled to a frequency translator to supply both the incident signal and local oscillator signal and thus permit reception of amplitude modulated video bandwidth signals through the atmosphere. This receiver is useful in scientific propagation experiments, tracking experiments, and communication experiments.

  12. Weather Data Receiver

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Northern Video Graphics, Inc. developed a low-cost satellite receiving system for users such as independent meteorologists, agribusiness firms, small airports or flying clubs, marine vessels and small TV stations. Called Video Fax, it is designed for use with certain satellites; the GOES (Geostationary Operational Environmental Satellite) spacecraft operated by the National Oceanic and Atmospheric Administration, the European Space Agency's Meteosat and Japan's Geostationary Meteorological Satellite. By dictum of the World Meteorological Organization, signals from satellites are available to anyone without cost so the Video Fax user can acquire signals directly from the satellite and cut out the middle man, enabling savings. Unit sells for about one-fifth the cost of the equipment used by TV stations. It consists of a two-meter antenna; a receiver; a microprocessor-controlled display computer; and a video monitor. Computer stores data from the satellites and converts it to an image which is displayed on the monitor. Weather map can be preserved as signal data on tape, or it can be stored in a video cassette as a permanent image.

  13. Discovering modulators of gene expression

    PubMed Central

    Babur, Özgün; Demir, Emek; Gönen, Mithat; Sander, Chris; Dogrusoz, Ugur

    2010-01-01

    Proteins that modulate the activity of transcription factors, often called modulators, play a critical role in creating tissue- and context-specific gene expression responses to the signals cells receive. GEM (Gene Expression Modulation) is a probabilistic framework that predicts modulators, their affected targets and mode of action by combining gene expression profiles, protein–protein interactions and transcription factor–target relationships. Using GEM, we correctly predicted a significant number of androgen receptor modulators and observed that most modulators can both act as co-activators and co-repressors for different target genes. PMID:20466809

  14. Direct Sequence Spread Spectrum (DSSS) Receiver, User Manual

    DTIC Science & Technology

    2008-01-01

    12 2.1.4 LVDS Digital I/O...Low probability of detection LPF Low-pass filter LSB Least significant bit/byte LSW Least significant word LVCMOS Low-voltage CMOS LVDS Low...mainboard back-end PCI and configuration buses. • High-density signalling to adjacent Slots. • A 42-way LVDS (or 84-way LVCMOS) Digital Input

  15. Digital Receiver Phase Meter

    NASA Technical Reports Server (NTRS)

    Marcin, Martin; Abramovici, Alexander

    2008-01-01

    The software of a commercially available digital radio receiver has been modified to make the receiver function as a two-channel low-noise phase meter. This phase meter is a prototype in the continuing development of a phase meter for a system in which radiofrequency (RF) signals in the two channels would be outputs of a spaceborne heterodyne laser interferometer for detecting gravitational waves. The frequencies of the signals could include a common Doppler-shift component of as much as 15 MHz. The phase meter is required to measure the relative phases of the signals in the two channels at a sampling rate of 10 Hz at a root power spectral density <5 microcycle/(Hz)1/2 and to be capable of determining the power spectral density of the phase difference over the frequency range from 1 mHz to 1 Hz. Such a phase meter could also be used on Earth to perform similar measurements in laser metrology of moving bodies. To illustrate part of the principle of operation of the phase meter, the figure includes a simplified block diagram of a basic singlechannel digital receiver. The input RF signal is first fed to the input terminal of an analog-to-digital converter (ADC). To prevent aliasing errors in the ADC, the sampling rate must be at least twice the input signal frequency. The sampling rate of the ADC is governed by a sampling clock, which also drives a digital local oscillator (DLO), which is a direct digital frequency synthesizer. The DLO produces samples of sine and cosine signals at a programmed tuning frequency. The sine and cosine samples are mixed with (that is, multiplied by) the samples from the ADC, then low-pass filtered to obtain in-phase (I) and quadrature (Q) signal components. A digital signal processor (DSP) computes the ratio between the Q and I components, computes the phase of the RF signal (relative to that of the DLO signal) as the arctangent of this ratio, and then averages successive such phase values over a time interval specified by the user.

  16. Solar thermal energy receiver

    NASA Technical Reports Server (NTRS)

    Baker, Karl W. (Inventor); Dustin, Miles O. (Inventor)

    1992-01-01

    A plurality of heat pipes in a shell receive concentrated solar energy and transfer the energy to a heat activated system. To provide for even distribution of the energy despite uneven impingement of solar energy on the heat pipes, absence of solar energy at times, or failure of one or more of the heat pipes, energy storage means are disposed on the heat pipes which extend through a heat pipe thermal coupling means into the heat activated device. To enhance energy transfer to the heat activated device, the heat pipe coupling cavity means may be provided with extensions into the device. For use with a Stirling engine having passages for working gas, heat transfer members may be positioned to contact the gas and the heat pipes. The shell may be divided into sections by transverse walls. To prevent cavity working fluid from collecting in the extensions, a porous body is positioned in the cavity.

  17. Optical communications receiver array

    NASA Astrophysics Data System (ADS)

    Saint Clair, Jonathan M.; Chan, Eric Y.; Koshinz, Dennis G.; Wilcken, Stephen K.; Soreide, David C.; Joshi, Atul; Durmus, Hakan

    2010-04-01

    One of the major challenges to free space laser communications and ladar is the impact of turbulence on beam propagation, one example of which is signal fading. These impacts can be exacerbated on airborne platforms by turbulence in the vicinity of the laser system aperture and the platform wake. There are a number of strategies to mitigate this, including adaptive optics, active flow control, and various dimensions of diversity: wavelength, polarization, temporal, and spatial diversity. In this paper we will discuss spatial diversity implemented in the focal region of optical telescopes. We will briefly compare this with other methods, describe results of requirements analysis of array features and optical configurations for various atmospheric turbulence states, and suggest several attractive configurations. We will also report on the design and test of one configuration, implemented in a prototype, and tested for noise performance, optical transmission, modulation bandwidth, and BER performance with our dynamic turbulence simulator. Early evidence shows significant BER improvements of several orders of magnitude at high turbulence fluctuation frequencies using this technique.

  18. Note: optical receiver system for 152-channel magnetoencephalography.

    PubMed

    Kim, Jin-Mok; Kwon, Hyukchan; Yu, Kwon-kyu; Lee, Yong-Ho; Kim, Kiwoong

    2014-11-01

    An optical receiver system composing 13 serial data restore/synchronizer modules and a single module combiner converted optical 32-bit serial data into 32-bit synchronous parallel data for a computer to acquire 152-channel magnetoencephalography (MEG) signals. A serial data restore/synchronizer module identified 32-bit channel-voltage bits from 48-bit streaming serial data, and then consecutively reproduced 13 times of 32-bit serial data, acting in a synchronous clock. After selecting a single among 13 reproduced data in each module, a module combiner converted it into 32-bit parallel data, which were carried to 32-port digital input board in a computer. When the receiver system together with optical transmitters were applied to 152-channel superconducting quantum interference device sensors, this MEG system maintained a field noise level of 3 fT/√Hz @ 100 Hz at a sample rate of 1 kSample/s per channel.

  19. Note: Optical receiver system for 152-channel magnetoencephalography

    SciTech Connect

    Kim, Jin-Mok; Kwon, Hyukchan; Yu, Kwon-kyu; Lee, Yong-Ho; Kim, Kiwoong

    2014-11-15

    An optical receiver system composing 13 serial data restore/synchronizer modules and a single module combiner converted optical 32-bit serial data into 32-bit synchronous parallel data for a computer to acquire 152-channel magnetoencephalography (MEG) signals. A serial data restore/synchronizer module identified 32-bit channel-voltage bits from 48-bit streaming serial data, and then consecutively reproduced 13 times of 32-bit serial data, acting in a synchronous clock. After selecting a single among 13 reproduced data in each module, a module combiner converted it into 32-bit parallel data, which were carried to 32-port digital input board in a computer. When the receiver system together with optical transmitters were applied to 152-channel superconducting quantum interference device sensors, this MEG system maintained a field noise level of 3 fT/√Hz @ 100 Hz at a sample rate of 1 kSample/s per channel.

  20. ADMX Receiver and Analysis

    NASA Astrophysics Data System (ADS)

    Malagon, Ana; ADMX Collaboration

    2016-03-01

    ADMX looks for the excess radiation deposited into a cavity from the conversion of a dark matter axion into a microwave photon. The sensitivity of the experiment increases by reducing the background thermal noise and minimizing the electronic noise of the readout system. The axion masses that the experiment can detect are determined by the resonant frequency of the cavity mode of interest, which is tuned using a two rod configuration. One can also increase the search rate by measuring the output from two cavity modes at once, which requires two separate readout schemes. I will discuss the ADMX dual-channel receiver which has been upgraded to have near quantum-limited sensitivity on both channels, and describe how the correct modes are verified, using simulations, in the presence of dense electromagnetic structure. I conclude by describing upgrades to the ADMX analysis which allow for real-time exclusion limits. Supported by DOE Grants DE-FG02-97ER41029, DE-FG02-96ER40956, DE- AC52-07NA27344, DE-AC03-76SF00098, and the Livermore LDRD program.

  1. DOT Transmit Module

    NASA Technical Reports Server (NTRS)

    Quirk, Kevin J.; Gin, Jonathan W.; Sahasrabudhe, Adit; Patawaran, Ferze D.; Nguyen, Danh H.; Nguyen, Huy

    2013-01-01

    The Deep Space Optical Terminal (DOT) transmit module demonstrates the DOT downlink signaling in a flight electronics assembly that can be qualified for deep space. The assembly has the capability to generate an electronic pulse-position modulation (PPM) waveform suitable for driving a laser assembly to produce the optical downlink signal. The downlink data enters the assembly through a serializer/ deserializer (SERDES) interface, and is encoded using a serially concatenated PPM (SCPPM) forward error correction code. The encoded data is modulated using PPM with an inter-symbol guard time to aid in receiver synchronization. Monitor and control of the assembly is via a low-voltage differential signal (LVDS) interface

  2. Improved thermal storage module for solar dynamic receivers

    SciTech Connect

    Beatty, R.L.; Lauf, R.J.

    1990-01-01

    This invention relates to a thermal storage apparatus and more particularly to an apparatus for use in conjunction with solar dynamic energy storage systems. The invention is comprised of a thermal energy storage system comprising a germanium phase change material and a graphite container.

  3. Waste receiving and processing facility module 1, detailed design report

    SciTech Connect

    Not Available

    1993-10-01

    WRAP 1 baseline documents which guided the technical development of the Title design included: (a) A/E Statement of Work (SOW) Revision 4C: This DOE-RL contractual document specified the workscope, deliverables, schedule, method of performance and reference criteria for the Title design preparation. (b) Functional Design Criteria (FDC) Revision 1: This DOE-RL technical criteria document specified the overall operational criteria for the facility. The document was a Revision 0 at the beginning of the design and advanced to Revision 1 during the tenure of the Title design. (c) Supplemental Design Requirements Document (SDRD) Revision 3: This baseline criteria document prepared by WHC for DOE-RL augments the FDC by providing further definition of the process, operational safety, and facility requirements to the A/E for guidance in preparing the design. The document was at a very preliminary stage at the onset of Title design and was revised in concert with the results of the engineering studies that were performed to resolve the numerous technical issues that the project faced when Title I was initiated, as well as, by requirements established during the course of the Title II design.

  4. New Packing Structure of Concentration Solar Receiver

    SciTech Connect

    Tsai, Shang-Yu; Lee, Yueh-Mu; Shih, Zun-Hao; Hong, Hwen-Fen; Shin, Hwa-Yuh; Kuo, Cherng-Tsong

    2010-10-14

    This paper presents a solution to the temperature issue in High Concentration Photovoltaic (HCPV) module device by using different thermal conductive material and packing structure. In general, the open-circuited voltage of a device reduces with the increase of temperature and therefore degrades its efficiency. The thermal conductive material we use in this paper, silicon, has a high thermal conductive coefficient (149 W/m{center_dot}K) and steady semiconductor properties which are suitable for the application of solar receiver in HCPV module. Solar cell was soldered on a metal-plated Si substrate with a thicker SiO{sub 2} film which acts as an insulating layer. Then it was mounted on an Al-based plate to obtain a better heat dissipating result.

  5. Accumulate Repeat Accumulate Coded Modulation

    NASA Technical Reports Server (NTRS)

    Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

    2004-01-01

    In this paper we propose an innovative coded modulation scheme called 'Accumulate Repeat Accumulate Coded Modulation' (ARA coded modulation). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes that are combined with high level modulation. Thus at the decoder belief propagation can be used for iterative decoding of ARA coded modulation on a graph, provided a demapper transforms the received in-phase and quadrature samples to reliability of the bits.

  6. High temperature solar thermal receiver

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A design concept for a high temperature solar thermal receiver to operate at 3 atmospheres pressure and 2500 F outlet was developed. The performance and complexity of windowed matrix, tube-header, and extended surface receivers were evaluated. The windowed matrix receiver proved to offer substantial cost and performance benefits. An efficient and cost effective hardware design was evaluated for a receiver which can be readily interfaced to fuel and chemical processes or to heat engines for power generation.

  7. High-temperature ceramic receivers

    SciTech Connect

    Jarvinen, P. O.

    1980-01-01

    An advanced ceramic dome cavity receiver is discussed which heats pressurized gas to temperatures above 1800/sup 0/F (1000/sup 0/C) for use in solar Brayton power systems of the dispersed receiver/dish or central receiver type. Optical, heat transfer, structural, and ceramic material design aspects of the receiver are reported and the development and experimental demonstration of a high-temperature seal between the pressurized gas and the high-temperature silicon carbide dome material is described.

  8. Coherent integrated receiver for highly linear microwave photonic links

    NASA Astrophysics Data System (ADS)

    Klamkin, Jonathan

    Phase modulation can be used to improve the signal-to-noise ratio and spurfree dynamic range (SFDR) of microwave photonic links because phase modulation is not limited in input modulation swing and is inherently linear using certain electro-optic devices. Traditional interferometer-based phase demodulators have a sinusoidal response therefore a novel approach is required for achieving linear coherent detection at the receive end of a photonic link employing phase modulation. In this work, a balanced receiver with feedback to a reference tracking phase modulator was developed. With sufficient feedback loop gain, the received signal phase is closely tracked and the phase detection falls within the linear regime of the interferometer response. For stable operation at high frequency the delay of the feedback loop must be kept short, therefore a monolithic approach is required to realize a compact receiver architecture. The monolithic photonic integrated circuit (PIC) developed here consists of a high power balanced uni-traveling-carrier photodiode (UTC-PD), a compact 2x2 multimode interference (MMI) coupler, and multi-quantum well reference phase modulators. This PIC is hybrid integrated with an electronic IC that provides transconductance amplification of the feedback signal for increased loop gain. Novel concepts such as charge compensation, partially depleted absorption, and absorption profile modification were incorporated into the design of the waveguide UTCPDs resulting in record output saturation current and linearity. Both general interference surface ridge (SR) MMI couplers and restricted interference deep ridge (DR) MMI couplers were explored, the latter for reducing the loop delay. Current injection tuning was incorporated into the MMI couplers for fine tuning the output power splitting ratio. The quantum well design of the reference phase modulators was optimized for realizing low Vpi, low insertion loss, low absorption modulation, and improved linearity

  9. Front-end technologies for robust ASR in reverberant environments—spectral enhancement-based dereverberation and auditory modulation filterbank features

    NASA Astrophysics Data System (ADS)

    Xiong, Feifei; Meyer, Bernd T.; Moritz, Niko; Rehr, Robert; Anemüller, Jörn; Gerkmann, Timo; Doclo, Simon; Goetze, Stefan

    2015-12-01

    This paper presents extended techniques aiming at the improvement of automatic speech recognition (ASR) in single-channel scenarios in the context of the REVERB (REverberant Voice Enhancement and Recognition Benchmark) challenge. The focus is laid on the development and analysis of ASR front-end technologies covering speech enhancement and feature extraction. Speech enhancement is performed using a joint noise reduction and dereverberation system in the spectral domain based on estimates of the noise and late reverberation power spectral densities (PSDs). To obtain reliable estimates of the PSDs—even in acoustic conditions with positive direct-to-reverberation energy ratios (DRRs)—we adopt the statistical model of the room impulse response explicitly incorporating DRRs, as well in combination with a novel proposed joint estimator for the reverberation time T 60 and the DRR. The feature extraction approach is inspired by processing strategies of the auditory system, where an amplitude modulation filterbank is applied to extract the temporal modulation information. These techniques were shown to improve the REVERB baseline in our previous work. Here, we investigate if similar improvements are obtained when using a state-of-the-art ASR framework, and to what extent the results depend on the specific architecture of the back-end. Apart from conventional Gaussian mixture model (GMM)-hidden Markov model (HMM) back-ends, we consider subspace GMM (SGMM)-HMMs as well as deep neural networks in a hybrid system. The speech enhancement algorithm is found to be helpful in almost all conditions, with the exception of deep learning systems in matched training-test conditions. The auditory feature type improves the baseline for all system architectures. The relative word error rate reduction achieved by combining our front-end techniques with current back-ends is 52.7% on average with the REVERB evaluation test set compared to our original REVERB result.

  10. Enhancements to - and Submillimetre - Integrated Circuit Receivers.

    NASA Astrophysics Data System (ADS)

    Veidt, Bruce George

    1995-01-01

    An important area of radio astronomy instrumentation is the development of sensitive receivers at millimetre - and submillimetre-wavelengths. Over the last decade, there has been steady progress in advancing the technology from using receivers based on mechanically machined waveguides and horn antennas to transmission lines and antennas fabricated using integrated circuit techniques. The motivation has been to simplify the fabrication of the receivers through the use of photolithography and etching. It is hoped that this will eventually lead to the development of focal plane arrays, which have many elements placed side-by-side forming a radio camera. The first part of this thesis addresses one of the problems with the integrated circuit technology, namely the fixed nature of the circuits, by examining one type of electrically-adjustable tuning. In those experiments, the bias voltage was modulated across the active device so as to change its tuning. Unfortunately the tuning effect was severely limited by the electrical nonlinearity of the device. Another part of this thesis builds upon the integrated nature of modern receivers by adding what, up until now, has been an external component: the Josephson effect suppression electromagnet. This technique will allow the receiving elements to be much simpler and smaller than would otherwise be the case. Finally, the last part of this thesis examines another method of constructing antennas and transmission lines using integrated circuit techniques. This work shows the feasibility of integrating a waveguide fabricated with integrated circuit technology with a diagonal horn antenna. This technique will provide another option for receiver designers.

  11. Development of a digital receiver for range imaging atmospheric radar

    NASA Astrophysics Data System (ADS)

    Yamamoto, Masayuki K.; Fujita, Toshiyuki; Abdul Aziz, Noor Hafizah Binti; Gan, Tong; Hashiguchi, Hiroyuki; Yu, Tian-You; Yamamoto, Mamoru

    2014-10-01

    In this paper, we describe a new digital receiver developed for a 1.3-GHz range imaging atmospheric radar. The digital receiver comprises a general-purpose software-defined radio receiver referred to as the Universal Software Radio Peripheral 2 (USRP2) and a commercial personal computer (PC). The receiver is designed to collect received signals at an intermediate frequency (IF) of 130 MHz with a sample rate of 10 MS s-1. The USRP2 digitizes IF received signals, produces IQ time series, and then transfers the IQ time series to the PC through Gigabit Ethernet. The PC receives the IQ time series, performs range sampling, carries out filtering in the range direction, decodes the phase-modulated received signals, integrates the received signals in time, and finally saves the processed data to the hard disk drive (HDD). Because only sequential data transfer from the USRP2 to the PC is available, the range sampling is triggered by transmitted pulses leaked to the receiver. For range imaging, the digital receiver performs real-time signal processing for each of the time series collected at different frequencies. Further, the receiver is able to decode phase-modulated oversampled signals. Because the program code for real-time signal processing is written in a popular programming language (C++) and widely used libraries, the signal processing is easy to implement, reconfigure, and reuse. From radar experiments using a 1 -μs subpulse width and 1-MHz frequency span (i.e., 2-MHz frequency bandwidth), we demonstrate that range imaging in combination with oversampling, which was implemented for the first time by the digital receiver, is able to resolve the fine-scale structure of turbulence with a vertical scale as small as 100 m or finer.

  12. Modulation techniques

    NASA Technical Reports Server (NTRS)

    Schilling, D. L.

    1982-01-01

    Bandwidth efficient digital modulation techniques, proposed for use on and/or applied to satellite channels, are reviewed. In a survey of recent works on digital modulation techniques, the performance of several schemes operating in various environments are compared. Topics covered include: (1) quadrature phase shift keying; (2) offset - QPSK and MSK; (3) combined modulation and coding; and (4) spectrally efficient modulation techniques.

  13. Advanced Stirling receiver development program, phase 1

    NASA Astrophysics Data System (ADS)

    Lurio, Charles A.

    1990-07-01

    Critical technology experiments were designed and developed to evaluate the Stirling cavity heat pipe receiver for a space solar power system. Theoretical criteria were applied to the design of a module for containing energy storage phase change material while avoiding thermal ratcheting. Zero-g drop tower tests, without phase change, were conducted to affirm that the bubble location required to avoid ratcheting could be achieved without the use of container materials that are wetted by the phase change material. A full scale module was fabricated, but not tested. A fabrication method was successfully developed for the sodium evaporator dome, with a sintered screen wick, to be used as the focal point for the receiver. Crushing of the screen during hydroforming was substantially reduced over the results of other researchers by using wax impregnation. Superheating of the sodium in the wick under average flux conditions is expected to be under 10K. A 2000K furnace which will simulate solar flux conditions for testing the evaporator dome was successfully built and tested.

  14. Advanced Stirling receiver development program, phase 1

    NASA Technical Reports Server (NTRS)

    Lurio, Charles A.

    1990-01-01

    Critical technology experiments were designed and developed to evaluate the Stirling cavity heat pipe receiver for a space solar power system. Theoretical criteria were applied to the design of a module for containing energy storage phase change material while avoiding thermal ratcheting. Zero-g drop tower tests, without phase change, were conducted to affirm that the bubble location required to avoid ratcheting could be achieved without the use of container materials that are wetted by the phase change material. A full scale module was fabricated, but not tested. A fabrication method was successfully developed for the sodium evaporator dome, with a sintered screen wick, to be used as the focal point for the receiver. Crushing of the screen during hydroforming was substantially reduced over the results of other researchers by using wax impregnation. Superheating of the sodium in the wick under average flux conditions is expected to be under 10K. A 2000K furnace which will simulate solar flux conditions for testing the evaporator dome was successfully built and tested.

  15. Analysis of Analog Photonic Links Employing Multiple-Channel (Arrayed) Receivers

    DTIC Science & Technology

    2008-11-07

    with an optical amplifier to boost the received optical signal level. While analog links utilizing single-channel and balanced receivers have been...utilizing single-channel and balanced receivers have been thoroughly analyzed, arrayed receiver architec- tures have received far less attention. In...output optical modulators and balanced -detection [8, 9] are frequently employed. This technique has been utilized alone to achieve the first multi

  16. Low cost omega navigation receiver

    NASA Technical Reports Server (NTRS)

    Lilley, R. W.

    1974-01-01

    The development of a low cost Omega navigation receiver is discussed. Emphasis is placed on the completion and testing of a modular, multipurpose Omega receiver which utilizes a digital memory-aided, phase-locked loop to provide phase measurement data to a variety of applications interfaces. The functional units contained in the prototype device are described. The receiver is capable of receiving and storing phase measurements for up to eight Omega signals and computes two switch-selectable lines of position, displaying this navigation data in chart-recorded form.

  17. Reducing Effects of Cross-Talk in a Radio Telescope Using Walsh Modulation

    NASA Astrophysics Data System (ADS)

    Chaudhari, Sandeep C.; Gupta, Yashwant; Kumar, Ajith; Shinde, Navnath D.; Gupta, Sweta; Vishwakarma, Ajay

    Traditional Walsh technique is used to eliminate cross-talk in a array of radio telescope where achieving synchronization between modulator and demodulator without compromising sensitivity is a real challenge. The paper describes a novel approach named Walsh Delay Hunting (WDH) to synchronize independently running modulator and demodulator with no additional hardware. This approach is unique and can easily be implemented in any existing radio telescope with minimal changes, thus by putting Walsh modulator at telescope and demodulation can be done in digital back-end. The scheme greatly reduces antenna electronics and overhead of sending synchronizing Walsh start pulse back to center station and vice versa. The paper describes WDH method and its feasibility study for Giant Meterwave Radio Telescope (GMRT) along with test results. The modulator is a low cost CPLD-based module and demodulation is done in a Reconfigurable Open Architecture Computing Hardware (ROACH)-based digitizer and packetizer. The scheme requires noise injection facility before modulator, which GMRT has for antenna calibration.

  18. UWB delay and multiply receiver

    SciTech Connect

    Dallum, Gregory E.; Pratt, Garth C.; Haugen, Peter C.; Romero, Carlos E.

    2013-09-10

    An ultra-wideband (UWB) delay and multiply receiver is formed of a receive antenna; a variable gain attenuator connected to the receive antenna; a signal splitter connected to the variable gain attenuator; a multiplier having one input connected to an undelayed signal from the signal splitter and another input connected to a delayed signal from the signal splitter, the delay between the splitter signals being equal to the spacing between pulses from a transmitter whose pulses are being received by the receive antenna; a peak detection circuit connected to the output of the multiplier and connected to the variable gain attenuator to control the variable gain attenuator to maintain a constant amplitude output from the multiplier; and a digital output circuit connected to the output of the multiplier.

  19. A wideband 240 GHz receiver for the submillimeter array

    NASA Astrophysics Data System (ADS)

    Tong, C.-Y. Edward; Grimes, Paul K.; Leiker, Patrick S.; Zeng, Lingzhen; Lu, Wei-Chun; Chen, Tse-Jun; Han, Chih-Chiang; Wang, Ming-Jye

    2016-07-01

    We report on the design of a 240 GHz double-side-band receiver for the Submillimeter Array (SMA). The heart of this receiver is a 3-junction series connected SIS mixer, which allows it to provide intermediate frequency (IF) output up to more than 12 GHz. We have custom built a low noise Amplifier-Multiplier Chain for use as the receiver's Local Oscillator module, which is tunable from 210 to 270 GHz. The receiver has demonstrated low noise performance in laboratory. 7 out of the 8 SMA antennas are now equipped with this receiver. The receiver has already participated in Event Horizon Telescope observations in April 2016, working with the SMA-200 receiver to provide dual polarization coverage for the EHT Hawaii Station. This receiver has enabled the SMA to provide 32 Gbit per second data stream to the EHT observations. We are currently trying to improve the on-sky beam co-alignment of this receiver with respect to other SMA receivers.

  20. Customizable Digital Receivers for Radar

    NASA Technical Reports Server (NTRS)

    Moller, Delwyn; Heavey, Brandon; Sadowy, Gregory

    2008-01-01

    Compact, highly customizable digital receivers are being developed for the system described in 'Radar Interferometer for Topographic Mapping of Glaciers and Ice Sheets' (NPO-43962), NASA Tech Briefs, Vol. 31, No. 7 (August 2007), page 72. The receivers are required to operate in unison, sampling radar returns received by the antenna elements in a digital beam-forming (DBF) mode. The design of these receivers could also be adapted to commercial radar systems. At the time of reporting the information for this article, there were no commercially available digital receivers capable of satisfying all of the operational requirements and compact enough to be mounted directly on the antenna elements. A provided figure depicts the overall system of which the digital receivers are parts. Each digital receiver includes an analog-to-digital converter (ADC), a demultiplexer (DMUX), and a field-programmable gate array (FPGA). The ADC effects 10-bit band-pass sampling of input signals having frequencies up to 3.5 GHz. The input samples are demultiplexed at a user-selectable rate of 1:2 or 1:4, then buffered in part of the FPGA that functions as a first-in/first-out (FIFO) memory. Another part of the FPGA serves as a controller for the ADC, DMUX, and FIFO memory and as an interface between (1) the rest of the receiver and (2) a front-panel data port (FPDP) bus, which is an industry-standard parallel data bus that has a high data-rate capability and multichannel configuration suitable for DBF. Still other parts of the FPGA in each receiver perform signal-processing functions. The digital receivers can be configured to operate in a stand-alone mode, or in a multichannel mode as needed for DBF. The customizability of the receiver makes it applicable to a broad range of system architectures. The capability for operation of receivers in either a stand-alone or a DBF mode enables the use of the receivers in an unprecedentedly wide variety of radar systems.

  1. Stirling Module Development Overview

    NASA Technical Reports Server (NTRS)

    Livingston, F. R.

    1984-01-01

    The solar parabolic dish Stirling engine electrically generating module consists of a solar collector coupled to a Stirling engine powered electrical generator. The module is designed to convert solar power to electrical power in parallel with numerous identical units coupled to an electrical utility power grid. The power conversion assembly generates up to 25 kilowatts at 480 volts potential/3 phase/alternating current. Piston rings and seals with gas leakage have not occurred, however, operator failures resulted in two burnt out receivers, while material fatigue resulted in a broken piston rod between the piston rod seal and cap seal.

  2. A Simple Radio Receiver Aids Understanding of Wireless Communication

    ERIC Educational Resources Information Center

    Straulino, S.; Orlando, A.

    2012-01-01

    The basic theory of radio broadcasting is discussed from an experimental point of view. First, concepts like wave modulation and tuning are explained with the use of instruments in the physics laboratory. Then, a very basic radio receiver is described and assembled, whose most important feature, like in the old "crystal radios", is the absence of…

  3. Deep space uplink receiver prototype for optical communications

    NASA Astrophysics Data System (ADS)

    Sburlan, S. E.; Birnbaum, K. M.; Farr, W. H.

    2011-03-01

    A hardware prototype of a flight receiver for deep space optical communications has been developed where a single detector array is used for acquisition, tracking, and high-speed data recovery. A counting algorithm accumulates pulses on every pixel in a photon-counting array and extracts signal information encoded with a nested modulation scheme.

  4. Hole-thru-laminate mounting supports for photovoltaic modules

    DOEpatents

    Wexler, Jason; Botkin, Jonathan; Culligan, Matthew; Detrick, Adam

    2015-02-17

    A mounting support for a photovoltaic module is described. The mounting support includes a pedestal having a surface adaptable to receive a flat side of a photovoltaic module laminate. A hole is disposed in the pedestal, the hole adaptable to receive a bolt or a pin used to couple the pedestal to the flat side of the photovoltaic module laminate.

  5. An NNSS satellite timing receiver

    NASA Technical Reports Server (NTRS)

    Jain, C. L.; Kumar, K.; Andharia, H. I.; Singh, M.; Dsouza, V.; Goel, V. K.; Sisodia, A. K.

    1982-01-01

    The U.S. Navy Navigation Satellite System, NNSS, offers a unique worldwide facility for precise time synchronization. Space Applications Centre (SAC) developed a simple timing receiver. Using this timing receiver first the internal time consistency of NNSS was studied and then its performance to synchronize time was compared with that of National Time Standard. The methodology of data analysis, results, and various sources of error which affect the time transfer accuracy were studied and described. The main source of error was found to be the receiver delay which varies with signal strength. It is possible to apply that this delay correction empirically provided signal strength is recorded.

  6. Design of simplified maximum-likelihood receivers for multiuser CPM systems.

    PubMed

    Bing, Li; Bai, Baoming

    2014-01-01

    A class of simplified maximum-likelihood receivers designed for continuous phase modulation based multiuser systems is proposed. The presented receiver is built upon a front end employing mismatched filters and a maximum-likelihood detector defined in a low-dimensional signal space. The performance of the proposed receivers is analyzed and compared to some existing receivers. Some schemes are designed to implement the proposed receivers and to reveal the roles of different system parameters. Analysis and numerical results show that the proposed receivers can approach the optimum multiuser receivers with significantly (even exponentially in some cases) reduced complexity and marginal performance degradation.

  7. QPPM receiver for free-space laser communications

    NASA Technical Reports Server (NTRS)

    Budinger, J. M.; Mohamed, J. H.; Nagy, L. A.; Lizanich, P. J.; Mortensen, D. J.

    1994-01-01

    A prototype receiver developed at NASA Lewis Research Center for direct detection and demodulation of quaternary pulse position modulated (QPPM) optical carriers is described. The receiver enables dual-channel communications at 325-Megabits per second (Mbps) per channel. The optical components of the prototype receiver are briefly described. The electronic components, comprising the analog signal conditioning, slot clock recovery, matched filter and maximum likelihood data recovery circuits are described in more detail. A novel digital symbol clock recovery technique is presented as an alternative to conventional analog methods. Simulated link degradations including noise and pointing-error induced amplitude variations are applied. The bit-error-rate performance of the electronic portion of the prototype receiver under varying optical signal-to-noise power ratios is found to be within 1.5-dB of theory. Implementation of the receiver as a hybrid of analog and digital application specific integrated circuits is planned.

  8. Processing module operating methods, processing modules, and communications systems

    DOEpatents

    McCown, Steven Harvey; Derr, Kurt W.; Moore, Troy

    2014-09-09

    A processing module operating method includes using a processing module physically connected to a wireless communications device, requesting that the wireless communications device retrieve encrypted code from a web site and receiving the encrypted code from the wireless communications device. The wireless communications device is unable to decrypt the encrypted code. The method further includes using the processing module, decrypting the encrypted code, executing the decrypted code, and preventing the wireless communications device from accessing the decrypted code. Another processing module operating method includes using a processing module physically connected to a host device, executing an application within the processing module, allowing the application to exchange user interaction data communicated using a user interface of the host device with the host device, and allowing the application to use the host device as a communications device for exchanging information with a remote device distinct from the host device.

  9. Coe Receives 2007 Gilbert Award

    NASA Astrophysics Data System (ADS)

    Bogue, Scott W.; Coe, Robert S.

    2008-05-01

    Robert S. Coe received the 2007 William Gilbert Award at the 2007 AGU Fall Meeting in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  10. Stevenson received the Whipple award

    NASA Astrophysics Data System (ADS)

    Shoemaker, Eugene M.; Stevenson, David J.

    1996-02-01

    David J. Stevenson received the Whipple Award at the 1994 Spring Meeting in Baltimore. The award is given for outstanding scientific contributions to the field of planetology. The citation and Stevenson's response are given here.

  11. SDR implementation of the receiver of adaptive communication system

    NASA Astrophysics Data System (ADS)

    Skarzynski, Jacek; Darmetko, Marcin; Kozlowski, Sebastian; Kurek, Krzysztof

    2016-04-01

    The paper presents software implementation of a receiver forming a part of an adaptive communication system. The system is intended for communication with a satellite placed in a low Earth orbit (LEO). The ability of adaptation is believed to increase the total amount of data transmitted from the satellite to the ground station. Depending on the signal-to-noise ratio (SNR) of the received signal, adaptive transmission is realized using different transmission modes, i.e., different modulation schemes (BPSK, QPSK, 8-PSK, and 16-APSK) and different convolutional code rates (1/2, 2/3, 3/4, 5/6, and 7/8). The receiver consists of a software-defined radio (SDR) module (National Instruments USRP-2920) and a multithread reception software running on Windows operating system. In order to increase the speed of signal processing, the software takes advantage of single instruction multiple data instructions supported by x86 processor architecture.

  12. Design, fabrication, and bench testing of a solar chemical receiver

    NASA Technical Reports Server (NTRS)

    Summers, W. A.; Pierre, J. F.

    1981-01-01

    Solar thermal energy can be effectively collected, transported, stored, and utilized by means of a chemical storage and transport system employing the reversible SO2 oxidation reaction. A solar chemical receiver for SO3 thermal decomposition to SO2 and oxygen was analyzed. Bench tests of a ten foot section of a receiver module were conducted with dissociated sulfuric acid (SO3 and H2O) in an electrical furnace. Measured percent conversion of SO3 was 85% of the equilibrium value. Methods were developed to fabricate and assemble a complete receiver module. These methods included applying an aluminide coating to certain exposed surfaces, assembling concentric tubes with a wire spacer, applying a platinum catalyst to the tubing wall, and coiling the entire assembly into the desired configuration.

  13. Scanned Laser Illuminator/Receiver

    DTIC Science & Technology

    1976-11-01

    illustrate parallel development of the PIN diode /CCD sensor hybrid and the 100W laser . Al- though a detailed cost analysis for procurement of this large...pmww^^W .m^n.m .,** ■ —ssa^ AFAL-TR-76-184 \\ SCANNED LASER ILLUMINATOR/RECEIVER ^ R. A. Honzik and F. B. Warren ^•Martin Marietta...NUMBER 4. TITLE (and Sublille) SCANNED LASER ILLUMINATOR/RECEIVER 5, TYPE OF REPORT & PERIOD COVERED Final Technical Report Dec 75

  14. Streak camera receiver definition study

    NASA Technical Reports Server (NTRS)

    Johnson, C. B.; Hunkler, L. T., Sr.; Letzring, S. A.; Jaanimagi, P.

    1990-01-01

    Detailed streak camera definition studies were made as a first step toward full flight qualification of a dual channel picosecond resolution streak camera receiver for the Geoscience Laser Altimeter and Ranging System (GLRS). The streak camera receiver requirements are discussed as they pertain specifically to the GLRS system, and estimates of the characteristics of the streak camera are given, based upon existing and near-term technological capabilities. Important problem areas are highlighted, and possible corresponding solutions are discussed.

  15. Module Configuration

    DOEpatents

    Oweis, Salah; D'Ussel, Louis; Chagnon, Guy; Zuhowski, Michael; Sack, Tim; Laucournet, Gaullume; Jackson, Edward J.

    2002-06-04

    A stand alone battery module including: (a) a mechanical configuration; (b) a thermal management configuration; (c) an electrical connection configuration; and (d) an electronics configuration. Such a module is fully interchangeable in a battery pack assembly, mechanically, from the thermal management point of view, and electrically. With the same hardware, the module can accommodate different cell sizes and, therefore, can easily have different capacities. The module structure is designed to accommodate the electronics monitoring, protection, and printed wiring assembly boards (PWAs), as well as to allow airflow through the module. A plurality of modules may easily be connected together to form a battery pack. The parts of the module are designed to facilitate their manufacture and assembly.

  16. Performance measurement results for a 220 Mbps QPPM optical communication receiver with an EG/G Slik APD

    NASA Technical Reports Server (NTRS)

    Davidson, Frederic M.; Sun, Xiaoli

    1992-01-01

    The performance of a 220 Mbps quaternary pulse position modulation (QPPM) optical communication receiver with a 'Slik' silicon avalanche photodiode (APD) and a wideband transimpedance preamplifier in a small hybrid circuit module was measured. The receiver performance had been poor due to the lack of a wideband and low noise transimpedance preamplifier. With the new APB preamplifier module, the receiver achieved a bit error rate (BER) of 10 exp -6 at an average received input optical signal power of 4.2 nW, which corresponds to an average of 80 received (incident) signal photons per information bit.

  17. Central solar-energy receiver

    DOEpatents

    Not Available

    1981-10-27

    An improved tower-mounted central solar energy receiver for heating air drawn through the receiver by an induced draft fan is described. A number of vertically oriented, energy absorbing, fin-shaped slats are radially arranged in a number of concentric cylindrical arrays on top of the tower coaxially surrounding a pipe having air holes through which the fan draws air which is heated by the slats which receive the solar radiation from a heliostat field. A number of vertically oriented and wedge-shaped columns are radially arranged in a number of concentric cylindrical clusters surrounding the slat arrays. The columns have two mirror-reflecting sides to reflect radiation into the slat arrays and one energy absorbing side to reduce reradiation and reflection from the slat arrays.

  18. Receiver-exciter controller design

    NASA Technical Reports Server (NTRS)

    Jansma, P. A.

    1982-01-01

    A description of the general design of both the block 3 and block 4 receiver-exciter controllers for the Deep Space Network (DSN) Mark IV-A System is presented along with the design approach. The controllers are designed to enable the receiver-exciter subsystem (RCV) to be configured, calibrated, initialized and operated from a central location via high level instructions. The RECs are designed to be operated under the control of the DMC subsystem. The instructions are in the form of standard subsystem blocks (SSBs) received via the local area network (LAN). The centralized control provided by RECs and other DSCC controllers in Mark IV-A is intended to reduce DSN operations costs from the Mark III era.

  19. UWB communication receiver feedback loop

    DOEpatents

    Spiridon, Alex; Benzel, Dave; Dowla, Farid U.; Nekoogar, Faranak; Rosenbury, Erwin T.

    2007-12-04

    A novel technique and structure that maximizes the extraction of information from reference pulses for UWB-TR receivers is introduced. The scheme efficiently processes an incoming signal to suppress different types of UWB as well as non-UWB interference prior to signal detection. Such a method and system adds a feedback loop mechanism to enhance the signal-to-noise ratio of reference pulses in a conventional TR receiver. Moreover, sampling the second order statistical function such as, for example, the autocorrelation function (ACF) of the received signal and matching it to the ACF samples of the original pulses for each transmitted bit provides a more robust UWB communications method and system in the presence of channel distortions.

  20. Organic Rankine cycle receiver development

    NASA Technical Reports Server (NTRS)

    Haskins, H. J.

    1981-01-01

    The selected receiver concept is a direct-heated, once-through, monotube boiler operated at supercritical pressure. The cavity is formed by a cylindrical copper shell and backwall, with stainless steel tubing brazed to the outside surface. This core is surrounded by lightweight refractory insulation, load-bearing struts, and an outer case. The aperture plate is made of copper to provide long life by conduction and reradiation of heat away from the aperture lip. The receiver thermal efficiency is estimated to be 97 percent at rated conditions (energy transferred to toluene divided by energy incident on aperture opening). Development of the core manufacturing and corrosion protection methods is complete.

  1. Digital Receiver for Microwave Radiometry

    NASA Technical Reports Server (NTRS)

    Ellingson, Steven W.; Hampson, Grant A.; Johnson, Joel T.

    2005-01-01

    A receiver proposed for use in L-band microwave radiometry (for measuring soil moisture and sea salinity) would utilize digital signal processing to suppress interfering signals. Heretofore, radio frequency interference has made it necessary to limit such radiometry to a frequency band about 20 MHz wide, centered at .1,413 MHz. The suppression of interference in the proposed receiver would make it possible to expand the frequency band to a width of 100 MHz, thereby making it possible to obtain greater sensitivity and accuracy in measuring moisture and salinity

  2. Capacity of optical communication in loss and noise with general quantum Gaussian receivers

    NASA Astrophysics Data System (ADS)

    Takeoka, Masahiro; Guha, Saikat

    2014-04-01

    Laser-light (coherent-state) modulation is sufficient to achieve the ultimate (Holevo) capacity of classical communication over a lossy and noisy optical channel, but requires a receiver that jointly detects long modulated code words with highly nonlinear quantum operations, which are near-impossible to realize using current technology. We analyze the capacity of the lossy-noisy optical channel when the transmitter uses coherent-state modulation but the receiver is restricted to a general quantum-limited Gaussian receiver, i.e., one that may involve arbitrary combinations of Gaussian operations [passive linear optics: beam splitters and phase shifters; second-order nonlinear optics (or active linear optics): squeezers, along with homodyne or heterodyne detection measurements] and any amount of classical feedforward within the receiver. Under these assumptions, we show that the Gaussian receiver that attains the maximum mutual information is either homodyne detection, heterodyne detection, or time sharing between the two, depending upon the received power level. In other words, our result shows that to exceed the theoretical limit of conventional coherent optical communication, one has to incorporate non-Gaussian, i.e., third- or higher-order nonlinear operations in the receiver. Finally we compare our Gaussian receiver limit with experimentally feasible non-Gaussian receivers and show that in the regime of low received photon flux, it is possible to overcome the Gaussian receiver limit by relatively simple non-Gaussian receivers based on photon counting.

  3. Electro-optic microdisk RF-wireless receiver

    NASA Astrophysics Data System (ADS)

    Hossein-Zadeh, Mani

    A self-homodyne photonic receiver for transmitted carrier wireless links is demonstrated. The key innovations in this photonic RF-receiver are the design and implementation of a resonant LiNbO3 microdisk electro-optic modulator and novel RF down-conversion techniques that exploit the sensitivity of the microdisk for efficient RF down-conversion in the optical domain. By careful RF and optical design, simultaneous photonic and RF resonance is achieved in a LiNbO3 microdisk modulator resulting in a sensitivity of -80 dBm at 14.6 GHz. Two photonic RF down-conversion techniques are proposed to extract the baseband information from a RF signal that has a transmitted carrier modulation format. In the first approach we use an optical filter to modify the optical output spectrum of the microdisk modulator. Photodetection of the subsequent optical signal generates the baseband photocurrent. In the second technique the RF carrier and sidebands are mixed through nonlinear optical modulation in the microdisk and the down-converted signal is detected using a photodetector. In both cases the bandwidth of the photodetector and electronic circuitry are limited to that of the baseband signal. Receiver operation is demonstrated by demodulating up to 100 Mb/s digital data from a 14.6 GHz RF carrier frequency. Power efficiency, small volume, light weight and elimination of high-speed electronic components are the main specifications of the photonic RF-receiver that make it useful for applications like wireless LANs, fiber-feed backbone networks or video distribution systems.

  4. The Dolinar Receiver in an Information Theoretic Framework

    NASA Technical Reports Server (NTRS)

    Erkmen, Baris I.; Birnbaum, Kevin M.; Moision, Bruce E.; Dolinar, Samuel J.

    2011-01-01

    Optical communication at the quantum limit requires that measurements on the optical field be maximally informative, but devising physical measurements that accomplish this objective has proven challenging. The Dolinar receiver exemplifies a rare instance of success in distinguishing between two coherent states: an adaptive local oscillator is mixed with the signal prior to photodetection, which yields an error probability that meets the Helstrom lower bound with equality. Here we apply the same local-oscillator-based architecture with aninformation-theoretic optimization criterion. We begin with analysis of this receiver in a general framework for an arbitrary coherent-state modulation alphabet, and then we concentrate on two relevant examples. First, we study a binary antipodal alphabet and show that the Dolinar receiver's feedback function not only minimizes the probability of error, but also maximizes the mutual information. Next, we study ternary modulation consistingof antipodal coherent states and the vacuum state. We derive an analytic expression for a near-optimal local oscillator feedback function, and, via simulation, we determine its photon information efficiency (PIE). We provide the PIE versus dimensional information efficiency (DIE) trade-off curve and show that this modulation and the our receiver combination performs universally better than (generalized) on-off keying plus photoncounting, although, the advantage asymptotically vanishes as the bits-per-photon diverges towards infinity.

  5. Clark Receives Ocean Sciences Award

    NASA Astrophysics Data System (ADS)

    Roman, Michael R.; Clark, H. Lawrence

    2008-09-01

    H. Lawrence Clark received the 2008 Ocean Sciences Award at the 2008 Ocean Sciences Meeting, held 2-7 March 2008 in Orlando, Fla. The award is given in recognition of outstanding and long-standing service to the ocean sciences.

  6. Converting accounts receivable into cash.

    PubMed

    Folk, M D; Roest, P R

    1995-09-01

    In recent years, increasing numbers of healthcare providers have converted their accounts receivable into cash through a process called securitization. This practice has gained popularity because it provides a means to raise capital necessary to healthcare organizations. Although securitization transactions can be complex, they may provide increased financial flexibility to providers as they prepare for continuing change in the healthcare industry.

  7. Microwave blackbodies for spaceborne receivers

    NASA Technical Reports Server (NTRS)

    Stacey, J. M.

    1985-01-01

    The properties of microwave blackbody targets are explained as they apply to the calibration of spaceborne receivers. Also described are several practicable, blackbody targets used to test and calibrate receivers in the laboratory and in the thermal vacuum chamber. Problems with the precision and the accuracy of blackbody targets, and blackbody target design concepts that overcome some of the accuracy limitations present in existing target designs, are presented. The principle of the Brewster angle blackbody target is described where the blackbody is applied as a fixed-temperature test target in the laboratory and as a variable-temperature target in the thermal vacuum chamber. The reflectivity of a Brewster angle target is measured in the laboratory. From this measurement, the emissivity of the target is calculated. Radiatively cooled thermal suspensions are discussed as the coolants of blackbody targets and waveguide terminations that function as calibration devices in spaceborne receivers. Examples are given for the design of radiatively cooled thermal suspensions. Corrugated-horn antennas used to observe the cosmic background and to provide a cold-calibration source for spaceborne receivers are described.

  8. Vergano Receives David Perlman Award

    NASA Astrophysics Data System (ADS)

    Kelly, Sue

    2006-08-01

    Dan Vergano received the Perlman Award at the Joint Assembly Honors Ceremony, whichwas held on 25 May 2006 in Baltimore, Md. Vergano was honored for `The Debate's over:Globe is warming,' which describes the linkages between the science of climate change andthe complexity of technical and economic decisions facing its mitigation.

  9. Advances in SIS receiver technology

    NASA Technical Reports Server (NTRS)

    Frerking, M. A.

    1988-01-01

    Significant advances in SIS receiver technology since the last Asilomar meeting include: superconductor materials, integrated inductive tuning elements, and planar mounting structures. The effect of these advances is to push the upper frequency operating limit from about 600 to 1500 GHz, and to enhance the feasibility of focal plane arrays of heterodyne receivers. A fundamental high frequency operating limit of SIS mixers is set by the superconducting energy gap. A practical limitation for high frequency operation of SIS junctions is their parasitic capacitance and resistance. The performance of the mixer will be degraded by the Resistor-Capacitor rolloff. Several designs were reported for inductive elements integrated on the same substrate as the SIS junctions to tune out the bulk junction capacitance. Most millimeter SIS-based heterodyne receivers have used waveguide coupling structures. Technology has advanced to the state where programs that have a high probability of success can be defined to produce arrays of SIS receivers for frequencies as high as 1500 GHz.

  10. FQPSK-B viterbi receiver

    NASA Technical Reports Server (NTRS)

    Lee, Dennis K. (Inventor); Simon, Marvin K. (Inventor); Yan, Tsun-Yee (Inventor)

    2006-01-01

    An FQPSK-B receiver uses a simplified trellis system which uses combinations of FQPSK-B waveforms to correlate against an input signal. This enables reduction of the number of correlators that are used and the number of comparisons that are made by the correlators.

  11. Today's central receiver power plant

    NASA Astrophysics Data System (ADS)

    Alpert, D. J.; Kolb, G. J.; Chavez, J. M.

    1991-04-01

    For 15 years, the United States Department of Energy has worked with industry, both utilities and manufacturers, to develop the technology of solar central receiver power plants. In this type of plant, sunlight is concentrated by a field of sun-tracking mirrors, called heliostats, onto a centrally located receiver. The solar energy is collected in the form of a heated fluid, which is used to generate steam to power a conventional turbine generator. For a number of reasons, molten nitrate salt is now the preferred heat transfer fluid. Commercial plants will be sized between 100 and 200 MW. The impetus for developing central receivers comes from their unique advantages: (1) they produce clean, reliable, low-cost electricity; (2) they have practical energy storage that provides a high degree of dispatchability (annually up to 60 percent) - without fossil fuels; and (3) they are environmentally benign. Development efforts around the world have brought the technology to the brink of commercialization: The technical feasibility has been proven, and cost, performance, and reliability can be confidently predicted. Plans are currently being developed for the final steps toward commercial central receiver power plants.

  12. Performance of receivers in digital radio applications operating in the presence of noise and jamming

    NASA Astrophysics Data System (ADS)

    Bukofzer, Daniel C.

    The performance of digital communication systems operating in the presence of noise and jamming is analyzed and evaluated. Specifically, by modeling the jamming as additive colored Gaussian noise, and considering transmission via M-ary phase shift keyed (MPSK) modulation as well as Quadrature Amplitude Modulation (QAM), receiver performance is determined in terms of symbol error probability, P(S). The receiver analyzed is optimum for the modulation used when the channel interference consists of additive white Gaussian noise (AWGN) only, and does not process signals utilizing spread spectrum modulation or forward error correction schemes. Furthermore, the derived results for P(S) are used in order to optimize the shape of the colored noise (jamming) spectrum so as to cause maximum receiver degradation, subject to a jamming power constraint. Results on numerical evaluations are presented graphically, thus displaying receiver vulnerability to a specific form of jamming.

  13. High-Efficiency Power Module

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N. (Inventor); Wintucky, Edwin G. (Inventor)

    2015-01-01

    One or more embodiments of the present invention pertain to an all solid-state microwave power module. The module includes a plurality of solid-state amplifiers configured to amplify a signal using a low power stage, a medium power stage, and a high power stage. The module also includes a power conditioner configured to activate a voltage sequencer (e.g., bias controller) when power is received from a power source. The voltage sequencer is configured to sequentially apply voltage to a gate of each amplifier and sequentially apply voltage to a drain of each amplifier.

  14. High-Efficiency Power Module

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N (Inventor); Wintucky, Edwin G (Inventor)

    2013-01-01

    One or more embodiments of the present invention pertain to an all solid-state microwave power module. The module includes a plurality of solid-state amplifiers configured to amplify a signal using a low power stage, a medium power stage, and a high power stage. The module also includes a power conditioner configured to activate a voltage sequencer (e.g., bias controller) when power is received from a power source. The voltage sequencer is configured to sequentially apply voltage to a gate of each amplifier and sequentially apply voltage to a drain of each amplifier.

  15. Advanced development receiver thermal vacuum tests with cold wall

    NASA Technical Reports Server (NTRS)

    Sedgwick, Leigh M.

    1991-01-01

    The first ever testing of a full size solar dynamic heat receiver using high temperature thermal energy storage was completed. The heat receiver was designed to meet the requirements for operation on the Space Station Freedom. The purpose of the test program was to quantify the receiver thermodynamic performance, its operating temperatures, and thermal response to changes in environmental and power module interface boundary conditions. The heat receiver was tested in a vacuum chamber with liquid nitrogen cold shrouds and an aperture cold plate to partially simulate a low Earth orbit environment. The cavity of the receiver was heated by an infrared quartz lamp heater with 30 independently controllable zones to produce flux distributions typical of candidate concentrators. A closed Brayton cycle engine simulator conditioned a helium xenon gas mixture to specific interface conditions to simulate various operational modes of the solar dynamic power module. Inlet gas temperature, pressure, and flow rate were independently varied. A total of 58 simulated orbital cycles were completed during the test conduct period. The test hardware, execution of testing, test data, and post test inspections are described.

  16. The ALMA Band 9 receiver. Design, construction, characterization, and first light

    NASA Astrophysics Data System (ADS)

    Baryshev, A. M.; Hesper, R.; Mena, F. P.; Klapwijk, T. M.; van Kempen, T. A.; Hogerheijde, M. R.; Jackson, B. D.; Adema, J.; Gerlofsma, G. J.; Bekema, M. E.; Barkhof, J.; de Haan-Stijkel, L. H. R.; van den Bemt, M.; Koops, A.; Keizer, K.; Pieters, C.; Koops van het Jagt, J.; Schaeffer, H. H. A.; Zijlstra, T.; Kroug, M.; Lodewijk, C. F. J.; Wielinga, K.; Boland, W.; de Graauw, M. W. M.; van Dishoeck, E. F.; Jager, H.; Wild, W.

    2015-05-01

    Aims: We describe the design, construction, and characterization of the Band 9 heterodyne receivers (600-720 GHz) for the Atacama Large Millimeter/submillimeter Array (ALMA). First-light Band 9 data, obtained during ALMA commissioning and science verification phases, are presented as well. Methods: The ALMA Band 9 receiver units (so-called "cartridges"), which are installed in the telescope's front end, have been designed to detect and down-convert two orthogonal linear polarization components of the light collected by the ALMA antennas. The light entering the front end is refocused with a compact arrangement of mirrors, which is fully contained within the cartridge. The arrangement contains a grid to separate the polarizations and two beam splitters to combine each resulting beam with a local oscillator signal. The combined beams are fed into independent double-sideband mixers, each with a corrugated feedhorn coupling the radiation by way of a waveguide with backshort cavity into an impedance-tuned superconductor-insulator-superconductor (SIS) junction that performs the heterodyne down-conversion. Finally, the generated intermediate frequency (IF) signals are amplified by cryogenic and room-temperature HEMT amplifiers and exported to the telescope's IF back end for further processing and, finally, correlation. Results: The receivers have been constructed and tested in the laboratory and they show an excellent performance, complying with ALMA requirements. Performance statistics on all 73 Band 9 receivers are reported. Importantly, two different tunnel-barrier technologies (necessitating different tuning circuits) for the SIS junctions have been used, namely conventional AlOx barriers and the more recent high-current-density AlN barriers. On-sky characterization and tests of the performance of the Band 9 cartridges are presented using commissioning data. Continuum and line images of the low-mass protobinary IRAS 16293-2422 are presented which were obtained as part

  17. SAW correlator spread spectrum receiver

    DOEpatents

    Brocato, Robert W

    2014-04-01

    A surface acoustic wave (SAW) correlator spread-spectrum (SS) receiver is disclosed which utilizes a first demodulation stage with a chip length n and a second demodulation stage with a chip length m to decode a transmitted SS signal having a code length l=n.times.m which can be very long (e.g. up to 2000 chips or more). The first demodulation stage utilizes a pair of SAW correlators which demodulate the SS signal to generate an appropriate code sequence at an intermediate frequency which can then be fed into the second demodulation stage which can be formed from another SAW correlator, or by a digital correlator. A compound SAW correlator comprising two input transducers and a single output transducer is also disclosed which can be used to form the SAW correlator SS receiver, or for use in processing long code length signals.

  18. Femtosecond Photon-Counting Receiver

    NASA Technical Reports Server (NTRS)

    Krainak, Michael A.; Rambo, Timothy M.; Yang, Guangning; Lu, Wei; Numata, Kenji

    2016-01-01

    An optical correlation receiver is described that provides ultra-precise distance and/or time-pulse-width measurements even for weak (single photons) and short (femtosecond) optical signals. A new type of optical correlation receiver uses a fourth-order (intensity) interferometer to provide micron distance measurements even for weak (single photons) and short (femtosecond) optical signals. The optical correlator uses a low-noise-integrating detector that can resolve photon number. The correlation (range as a function of path delay) is calculated from the variance of the photon number of the difference of the optical signals on the two detectors. Our preliminary proof-of principle data (using a short-pulse diode laser transmitter) demonstrates tens of microns precision.

  19. Femtosecond Photon-Counting Receiver

    NASA Technical Reports Server (NTRS)

    Krainak, Michael A.; Rambo, Timothy M.; Yang, Guangning; Lu, Wei; Numata, Kenji

    2016-01-01

    An optical correlation receiver is described that provides ultra-precise distance and/or time/pulse-width measurements even for weak (single photons) and short (femtosecond) optical signals. A new type of optical correlation receiver uses a fourth-order (intensity) interferometer to provide micron distance measurements even for weak (single photons) and short (femtosecond) optical signals. The optical correlator uses a low-noise-integrating detector that can resolve photon number. The correlation (range as a function of path delay) is calculated from the variance of the photon number of the difference of the optical signals on the two detectors. Our preliminary proof-of principle data (using a short-pulse diode laser transmitter) demonstrates tens of microns precision.

  20. 30 GHz Commercial Satellite Receivers

    NASA Technical Reports Server (NTRS)

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

    1989-01-01

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

  1. Scintillation-Hardened GPS Receiver

    NASA Technical Reports Server (NTRS)

    Stephens, Donald R.

    2015-01-01

    CommLargo, Inc., has developed a scintillation-hardened Global Positioning System (GPS) receiver that improves reliability for low-orbit missions and complies with NASA's Space Telecommunications Radio System (STRS) architecture standards. A software-defined radio (SDR) implementation allows a single hardware element to function as either a conventional radio or as a GPS receiver, providing backup and redundancy for platforms such as the International Space Station (ISS) and high-value remote sensing platforms. The innovation's flexible SDR implementation reduces cost, weight, and power requirements. Scintillation hardening improves mission reliability and variability. In Phase I, CommLargo refactored an open-source GPS software package with Kalman filter-based tracking loops to improve performance during scintillation and also demonstrated improved navigation during a geomagnetic storm. In Phase II, the company generated a new field-programmable gate array (FPGA)-based GPS waveform to demonstrate on NASA's Space Communication and Navigation (SCaN) test bed.

  2. Femtosecond photon-counting receiver

    NASA Astrophysics Data System (ADS)

    Krainak, Michael A.; Rambo, Timothy M.; Yang, Guangning; Lu, Wei; Numata, Kenji

    2016-05-01

    An optical correlation receiver is described that provides ultra-precise distance and/or time/pulsewidth measurements even for weak (single photons) and short (femtosecond) optical signals. A new type of optical correlation receiver uses a fourth-order (intensity) interferometer to provide micron distance measurements even for weak (single photons) and short (femtosecond) optical signals. The optical correlator uses a low-noise-integrating detector that can resolve photon number. The correlation (range as a function of path delay) is calculated from the variance of the photon number of the difference of the optical signals on the two detectors. Our preliminary proof-of principle data (using a short-pulse diode laser transmitter) demonstrates tens of microns precision.

  3. The Back End of the Fuel Cycle Moves Front and Center

    SciTech Connect

    Isaacs, T; Choi, J

    2005-11-02

    For many years, the commercial nuclear business has remained relatively stable in many ways. That is unlikely to be the case in the coming years. While some countries have called for the phase out of nuclear power and others have ordered a small number of new plants, the overall profile of the nuclear power business has changed little. The number of countries with nuclear power plants is not much different than 10 years ago and the total number of operating plants has increased only slightly. Commercial enrichment and reprocessing services have remained the province of a few countries and consortia. Repository programs have moved forward slowly in some cases, backward in others, with a very small number making substantial progress. We are now witnessing the beginnings of serious change, with significant consequences for the future nuclear regime. Business as usual will not be the business of the future. The way the nuclear and policy community respond will have much to do with energy adequacy, national security, international stability, and environmental consequences including waste management and disposal. A number of events and trends are becoming increasingly apparent and are cause for both opportunity and caution: (1) New nuclear power plant orders are likely to grow and spread, particularly in the developing world, e.g. China and India. (2) The growing recognition that the developing world will be a major competitor for limited energy resources is raising awareness in the developed world regarding concerns for future energy security. (3) Clearer evidence of the effects of greenhouse gas emissions on global warming, largely from the burning of fossil fuels, is creating more attention on the environmental benefits of nuclear power. (4) The last decade has shown unequivocal evidence of countries lying, cheating on their NPT obligation, and covertly carrying out nuclear weapons-related activities. Some countries have suggested their presumed need for a domestic nuclear fuel cycle as a rationale to pursue enrichment and/or reprocessing capabilities, which would move them to the doorstep of being nuclear weapons capable. The DPRK even took the action to abrogate the NPT to hold on to its nuclear weapons program. (5) 9/11 and other evidence have made it undeniable that terrorist groups would like to obtain weapons of mass destruction, particularly nuclear weapons, and would use them if they could. A number of initiatives have been proposed recently to allow for the growth and spread of nuclear power while limiting the justifications for additional countries to pursue the acquisition of enrichment or reprocessing capabilities. Enrichment or reprocessing are the only ways for countries to gain the indigenous capability to transform natural materials and fuel for and from nuclear power plants to directly weapons-usable materials.

  4. Silicon nitride based plasmonic components for CMOS back-end-of-line integration.

    PubMed

    Zhu, Shiyang; Lo, G Q; Kwong, D L

    2013-10-07

    Silicon nitride waveguides provide low propagation loss but weak mode confinement due to the relatively small refractive index contrast between the Si₃N₄ core and the SiO2 cladding. On the other hand, metal-insulator-metal (MIM) plasmonic waveguides offer strong mode confinement but large propagation loss. In this work, MIM-like plasmonic waveguides and passive devices based on horizontal Cu-Si₃N₄-Cu or Cu-SiO₂-Si₃N₄-SiO₂-Cu structures are integrated in the conventional Si₃N₄ waveguide circuits using standard CMOS backend processes, and are characterized around 1550-nm telecom wavelengths using the conventional fiber-waveguide-fiber method. The Cu-Si₃N₄(~100 nm)-Cu devices exhibit ~0.78-dB/μm propagation loss for straight waveguides, ~38% coupling efficiency with the conventional 1-μm-wide Si₃N₄ waveguide through a 2-μm-long taper coupler, ~0.2-dB bending loss for sharp 90° bends, and ~0.1-dB excess loss for ultracompact 1 × 2 and 1 × 4 power splitters. Inserting a ~10-nm SiO₂ layer between the Si3N4 core and the Cu cover (i.e., the Cu-SiO2(~10 nm)-Si₃N₄(~100 nm)-SiO2(~10 nm)-Cu devices), the propagation loss and the coupling efficiency are improved to ~0.37 dB/μm and ~52% while the bending loss and the excess loss are degraded to ~3.2 dB and ~2.1 dB, respectively. These experimental results are roughly consistent with the numerical simulation results after taking the influence of possible imperfect fabrication into account. Ultracompact plasmonic ring resonators with 1-μm radius are demonstrated with an extinction ratio of ~18 dB and a quality factor of ~84, close to the theoretical prediction.

  5. 40 CFR 63.499 - Back-end process provisions-reporting.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... determinations, flow rate measurements, and exit velocity determinations made during the compliance determination... reporting and recordkeeping procedures as required under § 63.506(e)(3) or (e)(8). The Administrator...

  6. 40 CFR 63.499 - Back-end process provisions-reporting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... National Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins § 63.499...), the owner or operator shall submit the information specified in § 63.498(c)(1). (2) For organic HAP... Status specified in § 63.506(e)(5). (1) The residual organic HAP content, adjusted for the control...

  7. 40 CFR 63.498 - Back-end process provisions-recordkeeping.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... National Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins § 63.498... be the crumb rubber dry weight of the rubber leaving the stripper. (iv) The organic HAP content of each sample. (2) The monthly weighted average organic HAP content, calculated in accordance with §...

  8. A persistent back-end for the ATLAS TDAQ online information service (P-BEAST)

    NASA Astrophysics Data System (ADS)

    Sicoe, Alexandru D.; Lehmann Miotto, Giovanna; Magnoni, Luca; Kolos, Serguei; Soloviev, Igor

    2012-06-01

    This paper describes P-BEAST, a highly scalable, highly available and durable system for archiving monitoring information of the trigger and data acquisition (TDAQ) system of the ATLAS experiment at CERN. Currently this consists of 20,000 applications running on 2,400 interconnected computers but it is foreseen to grow further in the near future. P-BEAST stores considerable amounts of monitoring information which would otherwise be lost. Making this data accessible, facilitates long term analysis and faster debugging. The novelty of this research consists of using a modern key-value storage technology (Cassandra) to satisfy the massive time series data rates, flexibility and scalability requirements entailed by the project. The loose schema allows the stored data to evolve seamlessly with the information flowing within the Information Service. An architectural overview of P-BEAST is presented alongside a discussion about the technologies considered as candidates for storing the data. The arguments which ultimately lead to choosing Cassandra are explained. Measurements taken during operation in production environment illustrate the data volume absorbed by the system and techniques for reducing the required Cassandra storage space overhead.

  9. Design Methodology for Back-End Database Machines in Distributed Environments.

    DTIC Science & Technology

    1984-05-01

    TechnologijfSyetem Intelligent secondary bubble memory, storage devices CASSM, RAP, RARES Filtering CAFS, VERSO, SURE Filters and Mass memory controller DBC...form depicted in figure 6.1. I I \\... -------- .-. %i$W𔃾 6.1 V- 40 - 6.2. Customisation Custom logic, predominately in the form of gate array today...Reading, Mass ., 1980 [Mo7Q] Moore, G. "VLSI: Some Fundamental Challenges. " IEEE Spectrum, April, 1979 [Ou81J Ousterhout J.K., "Caesar: An

  10. The Euro-VO Registry, Re-engineering the Back-end

    NASA Astrophysics Data System (ADS)

    Arviset, C.; Perdikeas, M.; Osuna, P.; Gonzalez, J.

    2015-09-01

    The Euro-VO Registry, located, developed and operated at ESAC, is one of the full searchable registries available worldwide, gathering information about all VO-compliant resources. The Euro-VO Registry serves as a registration point for European - and other countries- VO actors and data centres wishing to publish VO services. It harvests other registries to ensure its completeness so VO applications developers and VO users can use it to discover all VO resources, from Europe and from all other VO projects. The Euro-VO Registry provides as well a harvesting interface to other registries in the world to make sure the European VO services are also included in all other worldwide full registries. In particular, the new Euro-VO registry will be supporting the new RegTAP search interface for the relational registry allowing arbitrary ADQL queries against its contents over a compliant TAP service. The recently obsolete (for future developments) SOAP-based legacy search interface will also be supported for backwards compatibility purposes. Furthermore, in the context of the IVOA, some quality control and curation procedures for the registry resources are being defined. The Euro-VO Registry implements these procedures to ensure the high quality of the VO resources it references. This paper gives an overview of the recent development of the new Euro-VO Registry, together with its new curation facilities, both of which are being performed under a contract awarded to Neuropublic, under ESA special initiative to Greece.

  11. Working with Pedagogical Agents: Understanding the "Back End" of an Intelligent Tutoring System

    ERIC Educational Resources Information Center

    Wolfe, Christopher; Widmer, Colin L.; Weil, Audrey M.; Cedillos-Whynott, Elizabeth M.

    2015-01-01

    Students in an undergraduate psychology course on Learning and Cognition used SKO (formerly AutoTutor Lite), an Intelligent Tutoring System, to create interactive lessons in which a pedagogic agent (animated avatar) engages users in a tutorial dialogue. After briefly describing the technology and underlying psychological theory, data from an…

  12. Lower limits of line resistance in nanocrystalline back end of line Cu interconnects

    NASA Astrophysics Data System (ADS)

    Hegde, Ganesh; Bowen, R. Chris; Rodder, Mark S.

    2016-11-01

    The strong non-linear increase in the Cu interconnect line resistance with decreasing linewidth presents a significant obstacle to their continued downscaling. In this letter we use the first principles density functional theory based electronic structure of Cu interconnects to find the lower limits of their line resistance for metal linewidths corresponding to future technology nodes. We find that even in the absence of scattering due to grain boundaries, edge roughness or interfaces, quantum confinement causes a severe increase in the line resistance of Cu. We also find that when the simplest scattering mechanism in the grain boundary scattering dominated limit is added to otherwise coherent electronic transmission in monocrystalline nanowires, the lower limit of line resistance is significantly higher than projected roadmap requirements in the International Technology Roadmap for Semiconductors.

  13. Solar dynamics imaging system a back-end instrument for the proposed NLST

    NASA Astrophysics Data System (ADS)

    Ramesh, K. B.; Vasantharaju, N.; Hemanth, P.; Reardon, K.

    2016-12-01

    The Solar Dynamics Imaging System (SDIS) will be one of the focal plane instruments operated at the National Large Solar Telescope (NLST). The prime objective of the instrument is to obtain high spatial and temporal resolution images of the region of interest on the Sun in the wavelength range from 390 nm to 900 nm. The SDIS provides filtergrams using broad-band filters while preserving the Strehl ratio provided by the telescope. Furthermore, the SDIS is expected to provide observations that allow image reconstruction to extract wave front information and achieve a homogenous image quality over the entire FOV.

  14. Frequency Diverse Array Receiver Architectures

    DTIC Science & Technology

    2015-06-29

    fielded systems. The FDA architecture intrinsically covers multiple diversity domains therefore, naturally lends it self to a multi-mission, multi-mode...dependent characteristics of the FDA and the periodic nature of the beam paterns. 7 Chapter 3 Linear Array Receiver Architectures We aim to design, clarify...flexibility in steering the beam. 3.1.1 FDA Time Dependency Spatial Pattern Due to the time dependency and periodic nature of the FDA spatial patterns a

  15. Thompson receives 1994 Bowen award

    NASA Astrophysics Data System (ADS)

    Green, David H.; Thompson, Alan Bruce

    At the Spring Meeting in Baltimore, May 23, 1994, Alan Bruce Thompson of the Eidgenossiche Technische Hochschule, Zurich, received the 1994 N. L. Bowen Award of the Volcanology, Geochemsitry, and Petrology section, which is given for a single outstanding contribution to volcanology, geochemistry, or petrology made during the preceding 5 years. The award was presented by David H. Green of the Research School of Earth Sciences. The citation and response are given here.

  16. Digital-data receiver synchronization

    DOEpatents

    Smith, Stephen F.; Turner, Gary W.

    2005-08-02

    Digital-data receiver synchronization is provided with composite phase-frequency detectors, mutually cross-connected comparison feedback or both to provide robust reception of digital data signals. A single master clock can be used to provide frequency signals. Advantages can include fast lock-up time in moderately to severely noisy conditions, greater tolerance to noise and jitter when locked, and improved tolerance to clock asymmetries.

  17. WRAP Module 1 sampling and analysis plan

    SciTech Connect

    Mayancsik, B.A.

    1995-03-24

    This document provides the methodology to sample, screen, and analyze waste generated, processed, or otherwise the responsibility of the Waste Receiving and Processing Module 1 facility. This includes Low-Level Waste, Transuranic Waste, Mixed Waste, and Dangerous Waste.

  18. Ferrite attenuator modulation improves antenna performance

    NASA Technical Reports Server (NTRS)

    Hooks, J. C.; Larson, S. G.; Shorkley, F. H.; Williams, B. T.

    1970-01-01

    Ferrite attenuator inserted into appropriate waveguide reduces the gain of the antenna element which is causing interference. Modulating the ferrite attenuator to change the antenna gain at the receive frequency permits ground tracking until the antenna is no longer needed.

  19. Digital Demodulator For Advanced Receiver

    NASA Technical Reports Server (NTRS)

    Sadr, Ramin; Hurd, William J.

    1990-01-01

    Complexity and cost reduced by new design for half-band filters. Digital demodulator designed for use in reception of phase- and amplitude-modulated digital signals of bandwidths up to 15 MHz on microwave carriers. System performs coherent demodulation in phase and in quadrature with carrier locked in phase to intermediate frequency of 10 MHz. Design suitable for fabrication in very-large-scale integrated circuitry. Principal innovative feature of demodulator is design of half-band digital low-pass filters that remove sum-frequency components.

  20. Signal simulator model A-111. [signal source for Doppler tracking high data rate receivers

    NASA Technical Reports Server (NTRS)

    Flattau, T.; Mellars, J.

    1974-01-01

    A signal simulator designed to function as a signal source for Doppler tracking high data rate receivers is described. The simulator produces modulated signals whose carrier frequency can be varied between 200 and 900 MHz at rates greater than 20 MHz/sec. The modulation is phase shift keying with data rate up to 300 megabits per second.

  1. WRAP Module 1 waste analysis plan

    SciTech Connect

    Mayancsik, B.A.

    1995-09-22

    The purpose of this waste analysis plan is to document the necessary characterization, sampling, screening, analysis, and waste acceptance criteria for waste received at the WRAP Module 1. Waste expected to be received at WRAP Module 1 includes newly generated and retrieved waste. The newly generated waste will undergo verification prior to treatment, storage, or disposal. Retrieved waste from the burial grounds or above ground storage will undergo further characterization (as needed), treatment, supercompaction, and repackaging

  2. Analysis and Simulation of Disadvantaged Receivers for Multiple-Input Multiple-Output Communications Systems

    DTIC Science & Technology

    2010-09-01

    47 Figure 23. Simulated BER performance of a 2x2 MIMO-OFDM system with Alamouti space-time coding and 16 QAM modulation ...Spectral Density xiv PDF Probability Density Function QAM Quadrature Amplitude Modulation QPSK Quadrature Phase-Shift Keying RF Radio...of possible received symbols in a given modulation scheme (i.e., M- QAM ). It is clear that this will significantly reduce computational time

  3. Optimization of MLS receivers for multipath environments

    NASA Technical Reports Server (NTRS)

    Mcalpine, G. A.; Highfill, J. H., III; Tzeng, C. P. J.; Koleyni, G.

    1978-01-01

    Reduced order receiver (suboptimal receiver) analysis in multipath environments is presented. The origin and objective of MLS is described briefly. Signal modeling in MLS the optimum receiver is also included and a description of a computer oriented technique which was used in the simulation study of the suboptimal receiver is provided. Results and conclusion obtained from the research for the suboptimal receiver are reported.

  4. Modulated Entry

    NASA Technical Reports Server (NTRS)

    Grant, Frederick C.

    1960-01-01

    The technique of modulation, or variable coefficients, is discussed and the analytical formulation is reviewed. Representative numerical results of the use of modulation are shown for the lifting and nonlifting cases. These results include the effects of modulation on peak acceleration, entry corridor, and heat absorption. Results are given for entry at satellite speed and escape speed. The indications are that coefficient modulation on a vehicle with good lifting capability offers the possibility of sizable loading reductions or, alternatively, wider corridors; thus, steep entries become practical from the loading standpoint. The amount of steepness depends on the acceptable heating penalty. The price of sizable fractions of the possible gains does not appear to be excessive.

  5. Power module assemblies with staggered coolant channels

    DOEpatents

    Herron, Nicholas Hayden; Mann, Brooks S; Korich, Mark D

    2013-07-16

    A manifold is provided for supporting a power module assembly with a plurality of power modules. The manifold includes a first manifold section. The first face of the first manifold section is configured to receive the first power module, and the second face of the first manifold section defines a first cavity with a first baseplate thermally coupled to the first power module. The first face of the second manifold section is configured to receive the second power module, and the second face of the second manifold section defines a second cavity with a second baseplate thermally coupled to the second power module. The second face of the first manifold section and the second face of the second manifold section are coupled together such that the first cavity and the second cavity form a coolant channel. The first cavity is at least partially staggered with respect to second cavity.

  6. WRAP module 1 treatment plan

    SciTech Connect

    Mayancsik, B.A.

    1995-05-01

    This document provides the methodology to treat waste in the Waste Receiving and Processing Module 1 facility to meet the Resource Conservation and Recovery Act (RCRA) land disposal restrictions or the Waste Isolation and Pilot Plant waste acceptance criteria. This includes Low-Level Mixed Waste, Transuranic Waste, and Transuranic Mixed Waste.

  7. Digital receiver study and implementation

    NASA Technical Reports Server (NTRS)

    Fogle, D. A.; Lee, G. M.; Massey, J. C.

    1972-01-01

    Computer software was developed which makes it possible to use any general purpose computer with A/D conversion capability as a PSK receiver for low data rate telemetry processing. Carrier tracking, bit synchronization, and matched filter detection are all performed digitally. To aid in the implementation of optimum computer processors, a study of general digital processing techniques was performed which emphasized various techniques for digitizing general analog systems. In particular, the phase-locked loop was extensively analyzed as a typical non-linear communication element. Bayesian estimation techniques for PSK demodulation were studied. A hardware implementation of the digital Costas loop was developed.

  8. Helping dentists manage accounts receivable.

    PubMed

    Scott, J

    2001-01-01

    First Pacific Corporation (FPC) has worked with dental practices since 1961, providing personal services that optimize practice performance. In addition to being the premier service provider for administrative tasks in dental offices, they supply state-of-the-art hardware and accounts receivable management software. FPC designs and teaches practice development strategies, deliver on-site training, and much more. FPC is dedicated to the long-term professional success of dental clients, their staff, and their practices through a unique, integrated package of services. As a family-owned business, with headquarters in Salem, Oregon, FPC employs approximately two hundred staff who serve practices in twenty-two states.

  9. Identification coding schemes for modulated reflectance systems

    DOEpatents

    Coates, Don M.; Briles, Scott D.; Neagley, Daniel L.; Platts, David; Clark, David D.

    2006-08-22

    An identifying coding apparatus employing modulated reflectance technology involving a base station emitting a RF signal, with a tag, located remotely from the base station, and containing at least one antenna and predetermined other passive circuit components, receiving the RF signal and reflecting back to the base station a modulated signal indicative of characteristics related to the tag.

  10. Command and Service Module Communications

    NASA Technical Reports Server (NTRS)

    Interbartolo, Michael

    2009-01-01

    This viewgraph presentation examines Command and Service Module (CSM) Communications. The communication system's capabilities are defined, including CSM-Earth, CSM-Lunar Module and CSM-Extravehicular crewman communications. An overview is provided for S-band communications, including data transmission and receiving rates, operating frequencies and major system components (pre-modulation processors, unified S-band electronics, S-band power amplifier and S-band antennas). Additionally, data transmission rates, operating frequencies and the capabilities of VHF communications are described. Major VHF components, including transmitters and receivers, and the VHF multiplexer and antennas are also highlighted. Finally, communications during pre-launch, ascent, in-flight and entry are discussed. Overall, the CSM communication system was rated highly by flight controllers and crew. The system was mostly autonomous for both crew and flight controllers and no major issues were encountered during flight.

  11. Spread Spectrum Receiver Electromagnetic Interference (EMI) Test Guide

    NASA Technical Reports Server (NTRS)

    Wheeler, M. L.

    1998-01-01

    The objective of this test guide is to document appropriate unit level test methods and techniques for the performance of EMI testing of Direct Sequence (DS) spread spectrum receivers. Consideration of EMI test methods tailored for spread spectrum receivers utilizing frequency spreading, techniques other than direct sequence (such as frequency hopping, frequency chirping, and various hybrid methods) is beyond the scope of this test guide development program and is not addressed as part of this document EMI test requirements for NASA programs are primarily developed based on the requirements contained in MIL-STD-46 1 D (or earlier revisions of MIL-STD-46 1). The corresponding test method guidelines for the MIL-STD-461 D tests are provided in MIL-STD-462D. These test methods are well documented with the exception of the receiver antenna port susceptibility tests (intermodulation, cross modulation, and rejection of undesired signals) which must be tailored to the specific type of receiver that is being tested. Thus, test methods addressed in this guide consist only of antenna port tests designed to evaluate receiver susceptibility characteristics. MIL-STD-462D should be referred for guidance pertaining to test methods for EMI tests other than the antenna port tests. The scope of this test guide includes: (1) a discussion of generic DS receiver performance characteristics; (2) a summary of S-band TDRSS receiver operation; (3) a discussion of DS receiver EMI susceptibility mechanisms and characteristics; (4) a summary of military standard test guidelines; (5) recommended test approach and methods; and (6) general conclusions and recommendations for future studies in the area of spread spectrum receiver testing.

  12. Effect Of Phase Unbalance In Product Modulator

    NASA Technical Reports Server (NTRS)

    Nguyen, Tien M.

    1992-01-01

    Paper presents theoretical study of effect of phase unbalance in product modulator of phase-modulation transmitter in deep-space telemetry system upon performance of system. Mathematical model of product modulator used to derive equations for relative strengths of desired suppressed-carrier component and undesired residual-carrier component of transmitted signal. Also addresses effects of unsuppressed-carrier component on carrier-tracking phase-locked loop and bit detector in receiver.

  13. Flight test of 4-Hz and 30-Hz Omega receiver front-end

    NASA Technical Reports Server (NTRS)

    Wright, L.

    1976-01-01

    In-flight information was gathered on two Omega receiver analog modules, one having a 4-Hz bandwidth and the other a 30-Hz bandwidth. The Mini-O receiver was also monitored. An improved signal-to-noise characteristic of the narrower bandwidth front-end with negligible loss in dynamic range indicates that the 4-Hz front-end is the more desirable for the prototype Omega receivers. The Mini-O receiver was found to function quite satisfactorily on its second test flight, and has a very real potential for a low-cost, low-power, compact and light-weight Omega receiver.

  14. High-Rate Digital Receiver Board

    NASA Technical Reports Server (NTRS)

    Ghuman, Parminder; Bialas, Thomas; Brambora, Clifford; Fisher, David

    2004-01-01

    A high-rate digital receiver (HRDR) implemented as a peripheral component interface (PCI) board has been developed as a prototype of compact, general-purpose, inexpensive, potentially mass-producible data-acquisition interfaces between telemetry systems and personal computers. The installation of this board in a personal computer together with an analog preprocessor enables the computer to function as a versatile, highrate telemetry-data-acquisition and demodulator system. The prototype HRDR PCI board can handle data at rates as high as 600 megabits per second, in a variety of telemetry formats, transmitted by diverse phase-modulation schemes that include binary phase-shift keying and various forms of quadrature phaseshift keying. Costing less than $25,000 (as of year 2003), the prototype HRDR PCI board supplants multiple racks of older equipment that, when new, cost over $500,000. Just as the development of standard network-interface chips has contributed to the proliferation of networked computers, it is anticipated that the development of standard chips based on the HRDR could contribute to reductions in size and cost and increases in performance of telemetry systems.

  15. Sheeley Receives 2009 Hale Prize

    NASA Astrophysics Data System (ADS)

    Tretkoff, Ernie

    2009-05-01

    Neil Sheeley Jr., of the Space Science Division of the Naval Research Laboratory (NRL), has been awarded the 2009 George Ellery Hale Prize by the Solar Physics Division of the American Astronomical Society (AAS). The international award recognizes work in solar astronomy done over an extended period of time. Sheeley will receive the award in June at the AAS meeting in Pasadena, Calif. Sheeley is cited "for his continuing outstanding contributions to our understanding of the solar magnetic field, coronal holes, and coronal mass ejections. His wide-ranging observational and theoretical work has laid the foundation for much current research in solar and heliospheric physics, and continues to have important applications in space weather prediction."

  16. A cryogenic receiver for EPR.

    PubMed

    Narkowicz, R; Ogata, H; Reijerse, E; Suter, D

    2013-12-01

    Cryogenic probes have significantly increased the sensitivity of NMR. Here, we present a compact EPR receiver design capable of cryogenic operation. Compared to room temperature operation, it reduces the noise by a factor of ≈2.5. We discuss in detail the design and analyze the resulting noise performance. At low microwave power, the input noise density closely follows the emission of a cooled 50Ω resistor over the whole measurement range from 20K up to room temperature. To minimize the influence of the microwave source noise, we use high microwave efficiency (≈1.1-1.7mTW(-1/2)) planar microresonators. Their efficient conversion of microwave power to magnetic field permits EPR measurements with very low power levels, typically ranging from a few μW down to fractions of nW.

  17. Preamplifier Noise in VLF Receivers

    NASA Technical Reports Server (NTRS)

    Burhans, R. W.

    1978-01-01

    Noise specifications for junction field-effect transistors are presented in different ways depending on the particular semiconductor manufacturer. Arithmetic involved in converting these specifications to equivalent RMS noise in microvolts developed at the preamplifier input terminal is reviewed. These methods were useful for estimating the noise performance of high input impedance preamplifiers used with E-field antennas operating in the range of 1 KHz to 10 MHz. Both the JFET MPF-102 transistor and the COS/MOS CA3600 transistor array provided amplification for VLF receivers where the internally generated noise was well below the atmospheric noise level. The CA3600 transistor array provided better performance because of the more symmetrical complementary MOS transistor transfer characteristics than a single N-type biased JFET transistor. The CMOS amplifier resulted in self-compensating gain characteristics over a very wide temperature range from -55 to +125 C.

  18. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1978-01-01

    NASA and the U.S. Coast Guard are working jointly to develop a helicopter transportable firefighting module that can shave precious minutes in combating shipboard or harbor fires. The program was undertaken in 1975, after a series of disastrous fires on oil tankers indicated a need for a lightweight, self-contained system that could be moved quickly to the scene of a fire. A prototype module was delivered to the Coast Guard last year and service testing is under way. The compact module weighs little more than a ton but it contains everything needed to fight a fire. The key component is a high output pump, which delivers up to 2,000 gallons of sea water a minute; the pump can be brought up to maximum output in only one minute after turning on the power source, a small Allison gas turbine engine. The module also contains hose, a foam nozzle and a spray nozzle, three sets of protective clothing for firefighters, and fuel for three hours operation. Designed to be assembled without special tools, the module can be set up for operation in less than 20 minutes.

  19. Microscale autonomous sensor and communications module

    DOEpatents

    Okandan, Murat; Nielson, Gregory N

    2014-03-25

    Various technologies pertaining to a microscale autonomous sensor and communications module are described herein. Such a module includes a sensor that generates a sensor signal that is indicative of an environmental parameter. An integrated circuit receives the sensor signal and generates an output signal based at least in part upon the sensor signal. An optical emitter receives the output signal and generates an optical signal as a function of the output signal. An energy storage device is configured to provide power to at least the integrated circuit and the optical emitter, and wherein the module has a relatively small diameter and thickness.

  20. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Aviation Power Supply's mobile firefighting module called Firefly II is mounted on a trailer pulled by a pickup truck. Trailer unit has two three- inch water cannons, and the pickup carries a six inch cannon. Completely self contained, module pumps 3,000 gallons of water a minute from hydrants or open bodies of water. Stream can go as far as 400 feet or can be employed in a high-loft mode to reach the tops of tall refinery towers. Compact Firefly II weighs only 2,500 pounds when fully fueled. Key component is a specially designed two stage pump. Power for the pump is generated by a gas turbine engine. Module also includes an electronic/pump controller, multiple hose connections, up to 1,500 feet of hose and fuel for four hours operation. Firefly trailer can be backed onto specially-built large fireboat.

  1. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Aviation Power Supply's mobile firefighting module called Firefly II is mounted on a trailer pulled by a pickup truck. Trailer unit has two three- inch water cannons, and the pickup carries a six inch cannon. Completely self contained, module pumps 3,000 gallons of water a minute from hydrants or open bodies of water. Stream can go as far as 400 feet or can be employed in a high-loft mode to reach the tops of tall refinery towers. Compact Firefly II weighs only 2,500 pounds when fully fueled. Key component is a specially designed two stage pump. Power for the pump is generated by a gas turbine engine. Module also includes an electronic/pump controller, multiple hose connections, up to 1,500 feet of hose and fuel for four hours operation. Firefly trailer can be backed onto specially-built large fireboat.

  2. Laminated thin film solar module

    SciTech Connect

    Berman, E.; Eisner, K.P.

    1986-11-25

    This patent describes a solar module comprising: a first untempered glass sheet having a first side forming a light receiving face of a solar module and a second side, a thin film photovoltaic device fabricated on the second side of the first glass sheet, a second tempered glass sheet spaced from the second side of the first sheet and forming the primary structural member of the solar module; and a pottant layer filling substantially all space between the first and second glass sheets and bonding the sheets together. This patent describes a solar module according to claim 1 further including a second thin film photovoltaic device fabricated on a surface of the second tempered glass sheet.

  3. Thermionic modules

    DOEpatents

    King, Donald B.; Sadwick, Laurence P.; Wernsman, Bernard R.

    2002-06-18

    Modules of assembled microminiature thermionic converters (MTCs) having high energy-conversion efficiencies and variable operating temperatures manufactured using MEMS manufacturing techniques including chemical vapor deposition. The MTCs incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. The MTCs also exhibit maximum efficiencies of just under 30%, and thousands of the devices and modules can be fabricated at modest costs.

  4. Integrated Cryogenic Satellite Communications Cross-Link Receiver Experiment

    NASA Technical Reports Server (NTRS)

    Romanofsky, R. R.; Bhasin, K. B.; Downey, A. N.; Jackson, C. J.; Silver, A. H.; Javadi, H. H. S.

    1995-01-01

    An experiment has been devised which will validate, in space, a miniature, high-performance receiver. The receiver blends three complementary technologies; high temperature superconductivity (HTS), pseudomorphic high electron mobility transistor (PHEMT) monolithic microwave integrated circuits (MMIC), and a miniature pulse tube cryogenic cooler. Specifically, an HTS band pass filter, InP MMIC low noise amplifier, HTS-sapphire resonator stabilized local oscillator (LO), and a miniature pulse tube cooler will be integrated into a complete 20 GHz receiver downconverter. This cooled downconverter will be interfaced with customized signal processing electronics and integrated onto the space shuttle's 'HitchHiker' carrier. A pseudorandom data sequence will be transmitted to the receiver, which is in low Earth orbit (LEO), via the Advanced Communication Technology Satellite (ACTS) on a 20 GHz carrier. The modulation format is QPSK and the data rate is 2.048 Mbps. The bit error rate (BER) will be measured in situ. The receiver is also equipped with a radiometer mode so that experiment success is not totally contingent upon the BER measurement. In this mode, the receiver uses the Earth and deep space as a hot and cold calibration source, respectively. The experiment closely simulates an actual cross-link scenario. Since the receiver performance depends on channel conditions, its true characteristics would be masked in a terrestrial measurement by atmospheric absorption and background radiation. Furthermore, the receiver's performance depends on its physical temperature, which is a sensitive function of platform environment, thermal design, and cryocooler performance. This empirical data is important for building confidence in the technology.

  5. Coupled Receiver/Decoders for Low-Rate Turbo Codes

    NASA Technical Reports Server (NTRS)

    Hamkins, Jon; Divsalar, Dariush

    2005-01-01

    been proposed for receiving weak single- channel phase-modulated radio signals bearing low-rate-turbo-coded binary data. Originally intended for use in receiving telemetry signals from distant spacecraft, the proposed receiver/ decoders may also provide enhanced reception in mobile radiotelephone systems. A radio signal of the type to which the proposal applies comprises a residual carrier signal and a phase-modulated data signal. The residual carrier signal is needed as a phase reference for demodulation as a prerequisite to decoding. Low-rate turbo codes afford high coding gains and thereby enable the extraction of data from arriving radio signals that might otherwise be too weak. In the case of a conventional receiver, if the signal-to-noise ratio (specifically, the symbol energy to one-sided noise power spectral density) of the arriving signal is below approximately 0 dB, then there may not be enough energy per symbol to enable the receiver to recover properly the carrier phase. One could solve the problem at the transmitter by diverting some power from the data signal to the residual carrier. A better solution . a coupled receiver/decoder according to the proposal . could reduce the needed amount of residual carrier power. In all that follows, it is to be understood that all processing would be digital and the incoming signals to be processed would be, more precisely, outputs of analog-to-digital converters that preprocess the residual carrier and data signals at a rate of multiple samples per symbol. The upper part of the figure depicts a conventional receiving system, in which the receiver and decoder are uncoupled, and which is also called a non-data-aided system because output data from the decoder are not used in the receiver to aid in recovering the carrier phase. The receiver tracks the carrier phase from the residual carrier signal and uses the carrier phase to wipe phase noise off the data signal. The receiver typically includes a phase-locked loop

  6. Measuring accounts receivable performance: a comprehensive method.

    PubMed

    Newton, R L

    1993-05-01

    Nonperforming assets, such as accounts receivable, are frequently cited as sources of financial difficulty for hospitals. Yet, many hospitals, relying on the traditional measure of accounts receivable--days revenue outstanding--may not have a true grasp of the real cost of their accounts receivable. The author discusses the costs imposed on a hospital by accounts receivable and describes three cost components that must be calculated if the true cost of accounts receivable is to be determined and controlled.

  7. Fluid absorption solar energy receiver

    NASA Technical Reports Server (NTRS)

    Bair, Edward J.

    1993-01-01

    A conventional solar dynamic system transmits solar energy to the flowing fluid of a thermodynamic cycle through structures which contain the gas and thermal energy storage material. Such a heat transfer mechanism dictates that the structure operate at a higher temperature than the fluid. This investigation reports on a fluid absorption receiver where only a part of the solar energy is transmitted to the structure. The other part is absorbed directly by the fluid. By proportioning these two heat transfer paths the energy to the structure can preheat the fluid, while the energy absorbed directly by the fluid raises the fluid to its final working temperature. The surface temperatures need not exceed the output temperature of the fluid. This makes the output temperature of the gas the maximum temperature in the system. The gas can have local maximum temperatures higher than the output working temperature. However local high temperatures are quickly equilibrated, and since the gas does not emit radiation, local high temperatures do not result in a radiative heat loss. Thermal radiation, thermal conductivity, and heat exchange with the gas all help equilibrate the surface temperature.

  8. Recent developments in superconducting receivers

    NASA Astrophysics Data System (ADS)

    Richards, Paul L.

    1990-09-01

    A description is given of recent work at Berkeley on superconducting mixers and detectors for infrared and millimeter wavelengths. The first report is a review article which summarizes the status of development of superconducting components for infrared and millimeter wave receivers. The next report describes accurate measurements and also theoretical modeling of an SIS quasiparticle waveguide mixer for W-band which uses very high quality Ta junctions. The best mixer noise is only 1.3 times the quantum limit. Both the mixer gain and the noise are in quantitative agreement with the quantum theory. Next, a report is given on measurements and theoretical modeling of the absorptivity (surface resistance) of high quality epitaxial films of the high Tc superconductor YBCO from 750 GHz to 21 THz. Finally, there are reports on the design and experimental performance of two different types of high Tc bolometric detectors. One is a conventional bolometer with a gold-black absorber. The other is an antenna coupled microbolometer.

  9. Lunar Receiving Laboratory Project History

    NASA Technical Reports Server (NTRS)

    Mangus, Susan; Larsen, William

    2004-01-01

    As early as 1959, the Working Group on Lunar Exploration within NASA advocated that 'one of the prime objectives of the first lunar landing mission should be the collection of samples for return to Earth, where they could be subjected to detailed study and analysis.' Within NASA, neither this group nor any other scientists working with the Agency were concerned about back contamination issues. Outside of NASA, back contamination concerns had been raised as early as 1960. Although NASA did not seem to pay any attention to the concerns at that time, the scientific community continued to be interested in the topic. In 1962 and again in 1963, as the Apollo Program loomed large, further discussions were held. These early discussions of back contamination did not make their way into NASA's administration, however, and when Manned Spacecraft Center personnel began to articulate early concepts for the Lunar Receiving Laboratory (LRL), the back contamination issue was not considered. Once this concern became a major focus, however, the LRL's development became increasingly complex. This is the history of that development.

  10. Recent developments in superconducting receivers

    SciTech Connect

    Richards, P.L.

    1990-09-01

    A description is given of recent work at Berkeley on superconducting mixers and detectors for infrared and millimeter wavelengths. The first report is a review article which summarizes the status of development of superconducting components for infrared and millimeter wave receivers. The next report describes accurate measurements and also theoretical modeling of an SIS quasiparticle waveguide mixer for W-band which uses very high quality Ta junctions. The best mixer noise is only 1.3 times the quantum limit. Both the mixer gain and the noise are in quantitative agreement with the quantum theory. Next, a report is given on measurements and theoretical modeling of the absorptivity (surface resistance) of high quality epitaxial films of the high {Tc} superconductor YBCO from 750 GHz to 21 THz. Finally, there are reports on the design and experimental performance of two different types of high {Tc} bolometric detectors. One is a conventional bolometer with a gold-black absorber. The other is an antenna coupled microbolometer.

  11. Thermal resistance model for CSP central receivers

    NASA Astrophysics Data System (ADS)

    de Meyer, O. A. J.; Dinter, F.; Govender, S.

    2016-05-01

    The receiver design and heliostat field aiming strategy play a vital role in the heat transfer efficiency of the receiver. In molten salt external receivers, the common operating temperature of the heat transfer fluid or molten salt ranges between 285°C to 565°C. The optimum output temperature of 565°C is achieved by adjusting the mass flow rate of the molten salt through the receiver. The reflected solar radiation onto the receiver contributes to the temperature rise in the molten salt by means of heat transfer. By investigating published work on molten salt external receiver operating temperatures, corresponding receiver tube surface temperatures and heat losses, a model has been developed to obtain a detailed thermographic representation of the receiver. The steady state model uses a receiver flux map as input to determine: i) heat transfer fluid mass flow rate through the receiver to obtain the desired molten salt output temperature of 565°C, ii) receiver surface temperatures iii) receiver tube temperatures iv) receiver efficiency v) pressure drop across the receiver and vi) corresponding tube strain per panel.

  12. A fully integrated CMOS super-regenerative wake-up receiver for EEG applications

    NASA Astrophysics Data System (ADS)

    Yiqi, Mao; Tongqiang, Gao; Xiaodong, Xu; Haigang, Yang; Xinxia, Cai

    2016-09-01

    A fully integrated super-regenerative wake-up receiver for wireless body area network applications is presented. The super-regeneration receiver is designed to receive OOK-modulated data from the base station. A low power waveform generator is adopted both to provide a quench signal for VCO and to provide a clock signal for the digital module. The receiver is manufactured in 0.18 μm CMOS process and the active area is 0.67 mm2. It achieves a sensitivity of -80 dBm for 10-3 BER with a data rate of 200 kbps. The power consumption of the super-regenerative wake-up receiver is about 2.16 mW. Project supported by the National Basic Research Program of China (No. 2014CB744600) and the National Natural Science Foundation of China (No. 61474120).

  13. Dense optical-electrical interface module

    SciTech Connect

    Paul Chang

    2000-12-21

    The DOIM (Dense Optical-electrical Interface Modules) is a custom-designed optical data transmission module employed in the upgrade of Silicon Vertex Detector of CDF experiment at Fermilab. Each DOIM module consists of a transmitter (TX) converting electrical differential input signals to optical outputs, a middle segment of jacketed fiber ribbon cable, and a receiver (RX) which senses the light inputs and converts them back to electrical signals. The targeted operational frequency is 53 MHz, and higher rate is achievable. This article outlines the design goals, implementation methods, production test results, and radiation hardness tests of these modules.

  14. Digital Front End for Wide-Band VLBI Science Receiver

    NASA Technical Reports Server (NTRS)

    Jongeling, Andre; Sigman, Elliott; Navarro, Robert; Goodhart, Charles; Rogstad, Steve; Chandra, Kumar; Finley, Sue; Trinh, Joseph; Soriano, Melissa; White, Les; Proctor, Robert; Rayhrer, Benno

    2006-01-01

    An upgrade to the very-long-baseline-interferometry (VLBI) science receiver (VSR) a radio receiver used in NASA's Deep Space Network (DSN) is currently being implemented. The current VSR samples standard DSN intermediate- frequency (IF) signals at 256 MHz and after digital down-conversion records data from up to four 16-MHz baseband channels. Currently, IF signals are limited to the 265-to-375-MHz range, and recording rates are limited to less than 80 Mbps. The new digital front end, denoted the Wideband VSR, provides improvements to enable the receiver to process wider bandwidth signals and accommodate more data channels for recording. The Wideband VSR utilizes state-of-the-art commercial analog-to-digital converter and field-programmable gate array (FPGA) integrated circuits, and fiber-optic connections in a custom architecture. It accepts IF signals from 100 to 600 MHz, sampling the signal at 1.28 GHz. The sample data are sent to a digital processing module, using a fiber-optic link for isolation. The digital processing module includes boards designed around an Advanced Telecom Computing Architecture (ATCA) industry-standard backplane. Digital signal processing implemented in FPGAs down-convert the data signals in up to 16 baseband channels with programmable bandwidths from 1 kHz to 16 MHz. Baseband samples are transmitted to a computer via multiple Ethernet connections allowing recording to disk at rates of up to 1 Gbps.

  15. Automatic Identification System modular receiver for academic purposes

    NASA Astrophysics Data System (ADS)

    Cabrera, F.; Molina, N.; Tichavska, M.; Araña, V.

    2016-07-01

    The Automatic Identification System (AIS) standard is encompassed within the Global Maritime Distress and Safety System (GMDSS), in force since 1999. The GMDSS is a set of procedures, equipment, and communication protocols designed with the aim of increasing the safety of sea crossings, facilitating navigation, and the rescue of vessels in danger. The use of this system not only is increasingly attractive to security issues but also potentially creates intelligence products throughout the added-value information that this network can transmit from ships on real time (identification, position, course, speed, dimensions, flag, among others). Within the marine electronics market, commercial receivers implement this standard and allow users to access vessel-broadcasted information if in the range of coverage. In addition to satellite services, users may request actionable information from private or public AIS terrestrial networks where real-time feed or historical data can be accessed from its nodes. This paper describes the configuration of an AIS receiver based on a modular design. This modular design facilitates the evaluation of specific modules and also a better understanding of the standard and the possibility of changing hardware modules to improve the performance of the prototype. Thus, the aim of this paper is to describe the system's specifications, its main hardware components, and to present educational didactics on the setup and use of a modular and terrestrial AIS receiver. The latter is for academic purposes and in undergraduate studies such as electrical engineering, telecommunications, and maritime studies.

  16. Structuring a sound securitization of healthcare receivables.

    PubMed

    Spradling, Mark

    2003-02-01

    Securitization of receivables allows healthcare providers to obtain an additional funding source by selling their accounts receivables to investors. A double-lock-box structure allows providers to securitize Medicare and Medicaid receivables without violating federal laws. A 2001 revision to the Uniform Commercial Code facilitates providers' securitization of private healthcare insurance receivables by underscoring rights of a purchaser of those receivables. HIPAA privacy standards appear to permit the use and disclosure of protected health information in crafting a securitization program. The securitization should be structured to shield the value of the receivables to be transferred from the potential backruptcies of the originator and the purchaser.

  17. Firefighting Module

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Firefly II pump module is NASA's Marshall Space Flight Center's commercial offshoot of a NASA/US Coast Guard program involving development of a lightweight, helicopter-transportable firefighting module for a quick response in combating shipboard or harbor fires. Operable on land or water, the Amphib One is equipped with 3 water cannons. When all 3 are operating, unit pumps more than 3,000 gallons a minute. Newly developed model used by U.S. Coast Guard can pump 5,000 gallons per minute. It was designed for applications such as firefighting onboard ship fires, emergency dockside water pumping, dewatering ships in danger of sinking, flood control, and emergency water supply at remote locations.

  18. Thermoelectric module

    DOEpatents

    Kortier, William E.; Mueller, John J.; Eggers, Philip E.

    1980-07-08

    A thermoelectric module containing lead telluride as the thermoelectric mrial is encapsulated as tightly as possible in a stainless steel canister to provide minimum void volume in the canister. The lead telluride thermoelectric elements are pressure-contacted to a tungsten hot strap and metallurgically bonded at the cold junction to iron shoes with a barrier layer of tin telluride between the iron shoe and the p-type lead telluride element.

  19. Linear modulator

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A study of frequency division multiplexing (FDM) systems was made for the purpose of determining the system performance that can be obtained with available state of the art components. System performance was evaluated on the basis of past experience, system analysis, and component evaluation. The system study was specifically directed to the area of FDM systems using subcarrier channel frequencies from 4 kHz to 200 kHz and channel information bandwidths of dc to 1, 2, 4, 8, and 16 kHz. The evaluation also assumes that the demodulation will be from a tape recorder which produces frequency modulation of + or - 1% on the signal due to the tape recorder wow and flutter. For the modulation system it is assumed that the pilot and carrier channel frequencies are stable to within + or - .005% and that the FM on the channel carriers is negligible. The modulator system was evaluated for the temperature range of -20 degree to +85 degree while the demodulator system was evaluated for operation at room temperature.

  20. How To Improve You Shipping and Receiving.

    ERIC Educational Resources Information Center

    Sturgeon, Julie

    2001-01-01

    Discusses how two universities improved their shipping and receiving operations and cut costs. Examples from the University of Texas at Dallas and John Hopkins University, Baltimore, Maryland, illustrate how they established greater shipping and receiving department efficiencies. (GR)

  1. Trough Receiver Heat Loss Testing (Presentation)

    SciTech Connect

    Lewandowski, A.; Feik, C.; Hansen, R.; Phillips, S.; Bingham, C.; Netter, J.; Forristal, R.; Burkholder, F.; Meglan, B.; Wolfrum, E.

    2006-02-01

    This presentation describes the design, fabrication, and qualification of an experimental capability for thermal loss testing of full-size trough receiver elements; and the testing on a variety of receivers.

  2. Optimization of MLS receivers for multipath environments

    NASA Technical Reports Server (NTRS)

    Mcalpine, G. A.; Irwin, S. H.; NELSON; Roleyni, G.

    1977-01-01

    Optimal design studies of MLS angle-receivers and a theoretical design-study of MLS DME-receivers are reported. The angle-receiver results include an integration of the scan data processor and tracking filter components of the optimal receiver into a unified structure. An extensive simulation study comparing the performance of the optimal and threshold receivers in a wide variety of representative dynamical interference environments was made. The optimal receiver was generally superior. A simulation of the performance of the threshold and delay-and-compare receivers in various signal environments was performed. An analysis of combined errors due to lateral reflections from vertical structures with small differential path delays, specular ground reflections with neglible differential path delays, and thermal noise in the receivers is provided.

  3. Telemetry Tests Of The Advanced Receiver II

    NASA Technical Reports Server (NTRS)

    Hinedi, Sami M.; Bevan, Roland P.; Marina, Miguel

    1993-01-01

    Report describes telemetry tests of Advanced Receiver II (ARX-II): digital radio receiving subsystem operating on intermediate-frequency output of another receiving subsystem called "multimission receiver" (MMR), detecting carrier, subcarrier, and data-symbol signals transmitted by spacecraft, and extracts Doppler information from signals. Analysis of data shows performance of MMR/ARX-II system comparable and sometimes superior to performances of Blk-III/BPA and Blk-III/SDA/SSA systems.

  4. Advanced salt receiver for solar power towers

    SciTech Connect

    Romero, M.; Sanchez, M.; Barrera, G.

    1995-11-01

    Falling Film receivers constitute an alternative to the traditional Salt in Tube receivers, widely used and tested in the Central Receiver Systems. This report presents an innovative concept of Internal Film Receiver (IFR), in which a film made of a eutectic mixture of molten salts flows down the back side of a stainless steel panel. The installation with 550 kW nominal power, molten salt inlet temperature 300 C and outlet temperature 550 C is described.

  5. Battle Keeps Solar Energy in Receiver

    NASA Technical Reports Server (NTRS)

    Mcdougal, A. R.; Hale, R. R.

    1982-01-01

    Mirror structure in solar concentrator reduces heat loss by reflection and reradiation. Baffle reflects entering rays back and forth in solar-concentrator receiver until they reach heat exchanger. Similarly, infrared energy reradiated by heat exchanger is prevented from leaving receiver. Surfaces of baffle and inside wall of receiver are polished and highly reflective at solar and infrared wavelengths.

  6. 29 CFR 1910.169 - Air receivers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 5 2011-07-01 2011-07-01 false Air receivers. 1910.169 Section 1910.169 Labor Regulations... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Compressed Gas and Compressed Air Equipment § 1910.169 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and...

  7. 29 CFR 1917.155 - Air receivers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as...

  8. 29 CFR 1917.155 - Air receivers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as...

  9. 29 CFR 1926.306 - Air receivers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Air receivers. 1926.306 Section 1926.306 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Tools-Hand and Power § 1926.306 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and other equipment used...

  10. 49 CFR 236.730 - Coil, receiver.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Coil, receiver. 236.730 Section 236.730 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Coil, receiver. Concentric layers of insulated wire wound around the core of a receiver of an...

  11. 49 CFR 393.88 - Television receivers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Television receivers. 393.88 Section 393.88... NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.88 Television receivers. Any motor vehicle equipped with a television viewer, screen or other means of visually receiving a...

  12. 49 CFR 393.88 - Television receivers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Television receivers. 393.88 Section 393.88... NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.88 Television receivers. Any motor vehicle equipped with a television viewer, screen or other means of visually receiving a...

  13. 49 CFR 393.88 - Television receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Television receivers. 393.88 Section 393.88... NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.88 Television receivers. Any motor vehicle equipped with a television viewer, screen or other means of visually receiving a...

  14. 49 CFR 393.88 - Television receivers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 false Television receivers. 393.88 Section 393.88... NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.88 Television receivers. Any motor vehicle equipped with a television viewer, screen or other means of visually receiving a...

  15. 49 CFR 393.88 - Television receivers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false Television receivers. 393.88 Section 393.88... NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.88 Television receivers. Any motor vehicle equipped with a television viewer, screen or other means of visually receiving a...

  16. Automatic Frequency Control For DMSK Receiver

    NASA Technical Reports Server (NTRS)

    Davarian, Faramaz; Sumida, Joe T.

    1989-01-01

    Report discusses performance of automatic frequency-control (AFC) subsystem of differential minimum-shift-keying receiver described in "DMSK Receiver for Moblile/Satellite Service," NPO-16659. Describes efforts to quantify behavior of system during acquisition of carrier signal; including theoretical analysis leading to numerical simulation, and measurements of performance of receiving equipment.

  17. A 200kW central receiver CPV system

    SciTech Connect

    Lasich, John Thomas, Ian Hertaeg, Wolfgang; Shirley, David; Faragher, Neil; Erenstrom, Neil; Carter, Sam; Cox, Brian; Zuo, Xinyi

    2015-09-28

    Raygen Resources has recently completed a Central Receiver CPV (CSPV) pilot plant in Central Victoria, Australia. The system is under final commissioning and initial operation is expected in late April 2015. The pilot demonstrates a full scale CSPV repeatable unit in a form that is representative of a commercial product and provides a test bed to prove out performance and reliability of the CSPV technology. Extensive testing of the system key components: dense array module, wireless solar powered heliostat and control system has been performed in the laboratory and on sun. Results from this key component testing are presented herein.

  18. A 200kW central receiver CPV system

    NASA Astrophysics Data System (ADS)

    Lasich, John; Thomas, Ian; Hertaeg, Wolfgang; Shirley, David; Faragher, Neil; Erenstrom, Neil; Carter, Sam; Cox, Brian; Zuo, Xinyi

    2015-09-01

    Raygen Resources has recently completed a Central Receiver CPV (CSPV) pilot plant in Central Victoria, Australia. The system is under final commissioning and initial operation is expected in late April 2015. The pilot demonstrates a full scale CSPV repeatable unit in a form that is representative of a commercial product and provides a test bed to prove out performance and reliability of the CSPV technology. Extensive testing of the system key components: dense array module, wireless solar powered heliostat and control system has been performed in the laboratory and on sun. Results from this key component testing are presented herein.

  19. Photovoltaic module and module arrays

    DOEpatents

    Botkin, Jonathan [El Cerrito, CA; Graves, Simon [Berkeley, CA; Lenox, Carl J. S. [Oakland, CA; Culligan, Matthew [Berkeley, CA; Danning, Matt [Oakland, CA

    2012-07-17

    A photovoltaic (PV) module including a PV device and a frame. The PV device has a PV laminate defining a perimeter and a major plane. The frame is assembled to and encases the laminate perimeter, and includes leading, trailing, and side frame members, and an arm that forms a support face opposite the laminate. The support face is adapted for placement against a horizontal installation surface, to support and orient the laminate in a non-parallel or tilted arrangement. Upon final assembly, the laminate and the frame combine to define a unitary structure. The frame can orient the laminate at an angle in the range of 3.degree.-7.degree. from horizontal, and can be entirely formed of a polymeric material. Optionally, the arm incorporates integral feature(s) that facilitate interconnection with corresponding features of a second, identically formed PV module.

  20. Photovoltaic module and module arrays

    DOEpatents

    Botkin, Jonathan; Graves, Simon; Lenox, Carl J. S.; Culligan, Matthew; Danning, Matt

    2013-08-27

    A photovoltaic (PV) module including a PV device and a frame, The PV device has a PV laminate defining a perimeter and a major plane. The frame is assembled to and encases the laminate perimeter, and includes leading, trailing, and side frame members, and an arm that forms a support face opposite the laminate. The support face is adapted for placement against a horizontal installation surface, to support and orient the laminate in a non-parallel or tilted arrangement. Upon final assembly, the laminate and the frame combine to define a unitary structure. The frame can orient the laminate at an angle in the range of 3.degree.-7.degree. from horizontal, and can be entirely formed of a polymeric material. Optionally, the arm incorporates integral feature(s) that facilitate interconnection with corresponding features of a second, identically formed PV module.

  1. On the Convergence of Iterative Receiver Algorithms Utilizing Hard Decisions

    NASA Astrophysics Data System (ADS)

    Rößler, Jürgen F.; Gerstacker, Wolfgang H.

    2010-12-01

    The convergence of receivers performing iterative hard decision interference cancellation (IHDIC) is analyzed in a general framework for ASK, PSK, and QAM constellations. We first give an overview of IHDIC algorithms known from the literature applied to linear modulation and DS-CDMA-based transmission systems and show the relation to Hopfield neural network theory. It is proven analytically that IHDIC with serial update scheme always converges to a stable state in the estimated values in course of iterations and that IHDIC with parallel update scheme converges to cycles of length 2. Additionally, we visualize the convergence behavior with the aid of convergence charts. Doing so, we give insight into possible errors occurring in IHDIC which turn out to be caused by locked error situations. The derived results can directly be applied to those iterative soft decision interference cancellation (ISDIC) receivers whose soft decision functions approach hard decision functions in course of the iterations.

  2. Research on GNSS receiver for spinning projectile in trajectory correction fuze

    NASA Astrophysics Data System (ADS)

    Xiao, Hongbing; Shen, Qiang; Zhao, Qing; Li, Huquan; Wang, Qin

    2007-11-01

    In trajectory correction fuze of spinning projectiles, the rotating rate experienced by fuze GNSS(Global Navigation Satellite System) receiver causes it positioning inaccurately for the amplitude or phase of signal from them are modulated by rotation. With multi-antenna array, this GNSS Receiver could improve signal-to-noise and anti-interference ability of the system. In addition, the special rotation demodulation loop with three channels helped the GNSS receiver demodulate rotation-modulated signals and thus provided correct position and attitude information. Besides, the quick searching and parallel algorithm realization based on SDR and FPGA were given here. At last, the effect of magnitude and phase modulation and roll rates were simulated, and primary data were obtained. The results show that it can capture and track the rotating projectiles effectively.

  3. More Efficient Solar Thermal-Energy Receiver

    NASA Technical Reports Server (NTRS)

    Dustin, M. O.

    1987-01-01

    Thermal stresses and reradiation reduced. Improved design for solar thermal-energy receiver overcomes three major deficiencies of solar dynamic receivers described in literature. Concentrator and receiver part of solar-thermal-energy system. Receiver divided into radiation section and storage section. Concentrated solar radiation falls on boiling ends of heat pipes, which transmit heat to thermal-energy-storage medium. Receiver used in number of applications to produce thermal energy directly for use or to store thermal energy for subsequent use in heat engine.

  4. A zero-power radio receiver.

    SciTech Connect

    Brocato, Robert Wesley

    2004-09-01

    This report describes both a general methodology and some specific examples of passive radio receivers. A passive radio receiver uses no direct electrical power but makes sole use of the power available in the radio spectrum. These radio receivers are suitable as low data-rate receivers or passive alerting devices for standard, high power radio receivers. Some zero-power radio architectures exhibit significant improvements in range with the addition of very low power amplifiers or signal processing electronics. These ultra-low power radios are also discussed and compared to the purely zero-power approaches.

  5. Optimization of MLS receivers for multipath environments

    NASA Technical Reports Server (NTRS)

    Mcalpine, G. A.; Highfill, J. H., III

    1979-01-01

    The angle tracking problems in microwave landing system receivers along with a receiver design capable of optimal performance in the multipath environments found in air terminal areas were studied. Included were various theoretical and evaluative studies like: (1) signal model development; (2) derivation of optimal receiver structures; and (3) development and use of computer simulations for receiver algorithm evaluation. The development of an experimental receiver for flight testing is presented. An overview of the work and summary of principal results and conclusions are reported.

  6. Fermilab Recycler Ring BPM Upgrade Based on Digital Receiver Technology

    NASA Astrophysics Data System (ADS)

    Webber, R.; Crisp, J.; Prieto, P.; Voy, D.; Briegel, C.; McClure, C.; West, R.; Pordes, S.; Mengel, M.

    2004-11-01

    Electronics for the 237 BPMs in the Fermilab Recycler Ring have been upgraded from a log-amplifier based system to a commercially produced digitizer-digital down converter based system. The hardware consists of a pre-amplifier connected to a split-plate BPM, an analog differential receiver-filter module and an 8-channel 80-MHz digital down converter VME board. The system produces position and intensity with a dynamic range of 30 dB and a resolution of ±10 microns. The position measurements are made on 2.5-MHz bunched beam and barrier buckets of the un-bunched beam. The digital receiver system operates in one of six different signal processing modes that include 2.5-MHz average, 2.5-MHz bunch-by-bunch, 2.5-MHz narrow band, unbunched average, un-bunched head/tail and 89-kHz narrow band. Receiver data is acquired on any of up to sixteen clock events related to Recycler beam transfers and other machine activities. Data from the digital receiver board are transferred to the front-end CPU for position and intensity computation on an on-demand basis through the VME bus. Data buffers are maintained for each of the acquisition events and support flash, closed orbit and turn-by-turn measurements. A calibration system provides evaluation of the BPM signal path and application programs.

  7. Compact 625-channel scannerless imaging laser radar receiver

    NASA Astrophysics Data System (ADS)

    Burns, Hoyt N.; Steiner, Todd D.; Hayden, David R.

    1996-06-01

    In 1995, under a USAF SBIR Phase I program, Burns Engineering Corporation investigated the application of new integrated photonics technologies and hybrid manufacturing processes to the miniaturization of an imaging laser radar receiver which has complete receiving and range counting circuitry for each pixel in a 25-by-25 element avalanche photodiode array. The `parallel multichannel' receiver (PMR) is a compact, robust, and modular laser radar subsystem which can produce high resolution 3D range imagery at 1 kHz frame rates without the use of a scanner. The modular PMR is attractive as a common module solution for a wide variety of high performance, low cost, autonomous laser-guided seeker applications. The system described illustrates one approach to integrating and packaging high-density photonic arrays and associated signal processing electronics to yield a high-performance imaging laser radar receiver using existing technology. Burns Engineering has been selected by the USAF to build a benchtop prototype, proof-of-concept demonstrator in a follow-on, SBIR Phase II program.

  8. The spectrogram correlation and transformation receiver, revisited.

    PubMed

    Peremans, H; Hallam, J

    1998-08-01

    The spectrogram correlation and transformation (SCAT) receiver has been proposed as a model for the receiver structure used by fm bats. The main contribution of this paper lies in the analysis of which features of the proposed model are responsible for its high accuracy in estimating arrival times of overlapping echoes. Apart from providing an answer to this question, the analysis will also indicate the limitations of the SCAT receiver. In particular, it is shown that the temporal block of the SCAT receiver returns erroneous results for interecho delays < 20 microseconds and for interecho amplitude ratios > 6 dB. It is also shown that the spectral block of the SCAT receiver generates spurious arrival times if more than two overlapping echoes are present. Finally, it is discussed how the characteristic measurement errors predicted by this analysis can be used to further investigate the accuracy of the SCAT receiver as a model of the receiver structure used by fm bats.

  9. Unity connecting module in SSPF

    NASA Technical Reports Server (NTRS)

    1998-01-01

    In the Space Station Processing Facility, the Unity connecting module, part of the International Space Station, is shown with Pressurized Mating Adapters 1 (left) and 2 (right) attached. Unity is scheduled to undergo testing of the common berthing mechanism to which other space station elements will dock. Unity is the primary payload on mission STS-88, targeted to launch Dec. 3, 1998. Other testing includes the Pad Demonstration Test to verify the compatibility of the module with the Space Shuttle as well as the ability of the astronauts to send and receive commands to Unity from the flight deck of the orbiter. Unity is expected to be ready for installation into the payload canister on Oct. 25, and transported to Launch Pad 39-A on Oct. 27. The Unity will be mated to the Russian-built Zarya control module which should already be in orbit at that time.

  10. Systems with Higher-order Modulation

    NASA Astrophysics Data System (ADS)

    Achiam, Yaakov; Kaplan, Arkady; Seimetz, Matthias

    The chapter covers concepts, systems aspects, and key components for higher-order modulation. The introductory section presents relevant variants of higher-order modulation formats and includes coherent detection and coherent optical orthogonal frequency-division multiplexing as well. The next section is devoted to system configurations with particular emphasis on transmitter structures and receiver concepts, whereas the subsequent chapter focuses on key components. Included are LiNbO3-based quadrature modulators, integrated coherent receivers, in particular 90° hybrids, ranging from new concepts to proven implementations. A treatment of integrated balanced four-branch receivers ranges from theoretical analysis to the presentation of commercially available devices. The chapter concludes with a discussion of system trends and expected future developments.

  11. Hybrid-integrated coherent receiver using silica-based planar lightwave circuit technology

    NASA Astrophysics Data System (ADS)

    Kim, Jong-Hoi; Choe, Joong-Seon; Choi, Kwang-Seong; Youn, Chun-Ju; Kim, Duk-Jun; Jang, Sun-Hyok; Kwon, Yong-Hwan; Nam, Eun-Soo

    2011-12-01

    A hybrid-integrated coherent receiver module has been achieved using flip-chip bonding technology, consisting of a silica-based 90°-hybrid planar lightwave circuit (PLC) platform, a spot-size converter integrated waveguide photodiode (SSC-WG-PD), and a dual-channel transimpedance amplifier (TIA). The receiver module shows error-free operation up to 40Gb/s and OSNR sensitivity of 11.5 dB for BER = 10-3 at 25 Gb/s.

  12. A sun-tracking environmental chamber for the outdoor quantification of CPV modules

    SciTech Connect

    Faiman, David Melnichak, Vladimir Bokobza, Dov Kabalo, Shlomo

    2014-09-26

    The paper describes a sun-tracking environmental chamber and its associated fast electronics, devised for the accurate outdoor characterization of CPV cells, receivers, mono-modules, and modules. Some typical measurement results are presented.

  13. Design and analysis of a novel concentrated photovoltaic-thermal receiver concept

    NASA Astrophysics Data System (ADS)

    Hangweirer, Manfred; Höller, Robert; Schneider, Hartmut

    2015-08-01

    Solar concentrators, which focus the sunlight on a small surface of solar cells, are a promising way of reducing expensive semiconductor area and thus also the energy generation costs of photovoltaics. This paper presents the design and the analysis of a concentrated photovoltaic (CPV) receiver for a linear Fresnel concentrator mirror module. The receiver is designed as hybrid concentrated photovoltaic-thermal (CPV-T) receiver, which enables simultaneous generation of power and heat in one compact receiver. Spectral splitting with selective absorptive media and thermal decoupling of heat carrier and solar cells improves the electrical efficiency. Computational fluid dynamics (CFD) simulations of various receiver-setups result in an electrical efficiency of the receiver up to 6.2% and a thermal efficiency of up to 61.2% at a specific selected operating design point. 62% of the wavelengths of the incoming solar spectrum between 500 to 1100 nm hit the solar cells.

  14. Highly Sensitive Electro-Optic Modulators

    SciTech Connect

    DeVore, Peter S

    2015-10-26

    There are very important diagnostic and communication applications that receive faint electrical signals to be transmitted over long distances for capture. Optical links reduce bandwidth and distance restrictions of metal transmission lines; however, such signals are only weakly imprinted onto the optical carrier, resulting in low fidelity transmission. Increasing signal fidelity often necessitates insertion of radio-frequency (RF) amplifiers before the electro-optic modulator, but (especially at high frequencies) RF amplification results in large irreversible distortions. We have investigated the feasibility of a Sensitive and Linear Modulation by Optical Nonlinearity (SALMON) modulator to supersede RF-amplified modulators. SALMON uses cross-phase modulation, a manifestation of the Kerr effect, to enhance the modulation depth of an RF-modulated optical wave. This ultrafast process has the potential to result in less irreversible distortions as compared to a RF-amplified modulator due to the broadband nature of the Kerr effect. Here, we prove that a SALMON modulator is a feasible alternative to an RFamplified modulator, by demonstrating a sensitivity enhancement factor greater than 20 and significantly reduced distortion.

  15. Receiver operating characteristic (ROC) analysis for characterizing synaptic efficacy.

    PubMed

    Chance, Frances S

    2007-02-01

    The role of background synaptic activity in cortical processing has recently received much attention. How do individual neurons extract information when embedded in a noisy background? When examining the impact of a synaptic input on postsynaptic firing, it is important to distinguish a change in overall firing probability from a true change in neuronal sensitivity to a particular input (synaptic efficacy) that corresponds to a change in detection performance. Here we study the impact of background synaptic input on neuronal sensitivity to individual synaptic inputs using receiver operating characteristic (ROC) analysis. We use the area under the ROC curve as a measure of synaptic efficacy, here defined as the ability of a postsynaptic action potential to identify a particular synaptic input event. An advantage of using ROC analysis to measure synaptic efficacy is that it provides a measure that is independent of postsynaptic firing rate. Furthermore, changes in mean excitation or inhibition, although affecting overall firing probability, do not modulate synaptic efficacy when measured in this way. Changes in overall conductance also affect firing probability but not this form of synaptic efficacy. Input noise, here defined as the variance of the input current, does modulate synaptic efficacy, however. This effect persists when the change in input variance is coupled with a change in conductance (as would result from changing background activity).

  16. High stable remote photoelectric receiver for interferometry

    NASA Astrophysics Data System (ADS)

    Yang, Hongxing; Zhu, Pengfei; Tan, Jiubin; Hu, Pengcheng; Fan, Zhigang

    2017-03-01

    A high sensitive and high stable remote photoelectric receiver has been developed to reduce noise and phase delay drift caused by thermal pollution and environmental interference. The phase delay drift model is analyzed and built based on a traditional photoelectric receiver. According to the model, a new mechanical isolation structure and a temperature control system are designed to keep the photoelectric receiver in a low constant temperature. Comparison experiments with traditional bias voltage compensation method and temperature control method are carried out between photoelectric receivers. The results verify that the output voltage fluctuation of photoelectric receiver used is reduced by 65% while the phase drift between measurement and reference photoelectric receivers decreases from 1.05° to 0.02°.

  17. Integration Window Position Estimation in TR Receivers

    SciTech Connect

    Nekoogar, F; Dowla, F; Spiridon, A

    2005-03-15

    Transmitted-reference (TR) receivers avoid the stringent synchronization requirements that exist in conventional pulse detection schemes. However, the performance of such receivers is highly sensitive to precise timing acquisition and tracking as well as the length of their integration window. This window in TR receivers defines the limits of the finite integrator prior to the final decision making block. In this paper, we propose a novel technique that allows us to extract the timing information of the integration window very accurately in UWB-TR receivers in the presence of channel noise. The principles of the method are presented and the BER performance of a modified UWB-TR receiver is investigated by computer simulation. Our studies show that the proposed estimation technique adds value to the conventional TR receiver structure with modest increase in complexity.

  18. Automatic Phase-Compensation Modules For Antennas

    NASA Technical Reports Server (NTRS)

    Terry, John D.; Kunath, Richard R., Jr.

    1996-01-01

    Automatic amplitude-controlling and phase-shifting modules developed in order to adaptively compensate for distortions in reflectors of microwave communication antennas. Antenna of type in question includes phased array of radiating antenna elements in focal plane of off-axis paraboloidal or similar reflector. Module lies on path of radio-frequency feed between each antenna element and radio-frequency transmitting/receiving equipment.

  19. Spread Spectrum Multi-h Modulation

    DTIC Science & Technology

    1988-07-01

    Digital Frequency Modulation Signal. Bell System Technical Journal, 54:1095-1125, July-August 1975. [54] Ramin Sadr . Receiver Design and Analysis for...Generalized Minimum Shift Keying Modulation Techniques. PhD thesis, University of California, Los Angeles, 1983. [55] Ramin Sadr and Jim Omura...ulation schemes was initially considered by Sadr and Omura in January, 1988 [55] following their research efforts in 1983 [54]. They concluded that direct

  20. Solar dynamic power module design

    NASA Technical Reports Server (NTRS)

    Secunde, Richard R.; Labus, Thomas L.; Lovely, Ronald G.

    1989-01-01

    Studies have shown that use of solar dynamic (SD) power for the growth eras of the Space Station Freedom program will result in life cycle cost savings when compared to power supplied by photovoltaic sources. In the SD power module, a concentrator collects and focuses solar energy into a heat receiver which has integral thermal energy storage. A power conversion unit (PCU) based on the closed Brayton thermodynamic cycle removes thermal energy from the receiver and converts that energy to electrical energy. Since the closed Brayton cycle is a single phase gas cycle, the conversion hardware (heat exchangers, turbine, compressor, etc.) can be designed for operation in low earth orbit, and tested with confidence in test facilities on earth before launch into space. The concentrator subassemblies will be aligned and the receiver/PCU/radiator combination completely assembled and charged with gas and cooling liquid on earth before launch to, and assembly on orbit.

  1. Absolute flux density calibrations: Receiver saturation effects

    NASA Technical Reports Server (NTRS)

    Freiley, A. J.; Ohlson, J. E.; Seidel, B. L.

    1978-01-01

    The effect of receiver saturation was examined for a total power radiometer which uses an ambient load for calibration. Extension to other calibration schemes is indicated. The analysis shows that a monotonic receiver saturation characteristic could cause either positive or negative measurement errors, with polarity depending upon operating conditions. A realistic model of the receiver was made by using a linear-cubic voltage transfer characteristic. The evaluation of measurement error for this model provided a means for correcting radio source measurements.

  2. Receiver System: Lessons Learned From Solar Two

    SciTech Connect

    LITWIN, ROBERT Z.; PACHECO, JAMES E.

    2002-03-01

    The Boeing Company fabricated the Solar Two receiver as a subcontractor for the Solar Two project. The receiver absorbed sunlight reflected from the heliostat field. A molten-nitrate-salt heat transfer fluid was pumped from a storage tank at grade level, heated from 290 to 565 C by the receiver mounted on top of a tower, then flowed back down into another storage tank. To make electricity, the hot salt was pumped through a steam generator to produce steam that powered a conventional Rankine steam turbine/generator. This evaluation identifies the most significant Solar Two receiver system lessons learned from the Mechanical Design, Instrumentation and Control, Panel Fabrication, Site Construction, Receiver System Operation, and Management from the perspective of the receiver designer/manufacturer. The lessons learned on the receiver system described here consist of two parts: the Problem and one or more identified Solutions. The appendix summarizes an inspection of the advanced receiver panel developed by Boeing that was installed and operated in the Solar Two receiver.

  3. Ceramic high temperature receiver design and tests

    NASA Technical Reports Server (NTRS)

    Davis, S. B.

    1982-01-01

    The High Temperature Solar Thermal Receiver, which was tested a Edwards AFB, CA during the winter of 1980-1981, evolved from technologies developed over a five year period of work. This receiver was tested at the Army Solar Furnace at White Sands, NM in 1976. The receiver, was tested successfully at 1768 deg F and showed thermal efficiencies of 85%. The results were sufficiently promising to lead ERDA to fund our development and test of a 250 kW receiver to measure the efficiency of an open cavity receiver atop a central tower of a heliostat field. This receiver was required to be design scalable to 10, 50, and 100 MW-electric sizes to show applicability to central power tower receivers. That receiver employed rectagular silicon carbide panels and vertical stanchions to achieve scalability. The construction was shown to be fully scalable; and the receiver was operated at temperatures up to 2000 deg F to achieve the performance goals of the experiment during tests at the GIT advanced components test facility during the fall of 1978.

  4. Receivers for the Microwave Radiometer on Juno

    NASA Technical Reports Server (NTRS)

    Maiwald, F.; Russell, D.; Dawson, D.; Hatch, W.; Brown, S.; Oswald, J.; Janssen, M.

    2009-01-01

    Six receivers for the MicroWave Radiometer (MWR) are currently under development at JPL. These receivers cover a frequency range of 0.6 to 22 GHz in approximately octave steps, with 4 % bandwidth. For calibration and diagnosis three noise diodes and a Dicke switch are integrated into each receiver. Each receiver is connected to its own antenna which is mounted with its bore sights perpendicular to the spin axis of the spacecraft. As the spacecraft spins at 2 RPM, the antenna field of view scans Jupiter's atmosphere from limb to nadir to limb, measuring microwave emission down to 1000-bar.

  5. Nursing process approach improves receivables management.

    PubMed

    Dias, K; Stockamp, D

    1992-09-01

    The "nursing process" is a systematic decision-making approach to problem solving based on open-system theory. This theory assumes that there is an on-going interchange between all system components. Components cannot be viewed in isolation, because decisions regarding one component will affect other components. Receivables management is similar to the nursing process, in that it involves constant diagnosis, assessment, and intervention in the work in process during all phases of the receivables cycle. In experiments that applied the nursing process concept to the management of accounts receivable in several hospitals, gross days in accounts receivable were reduced and cash flow was increased.

  6. Receiver System: Lessons Learned from Solar Two

    NASA Astrophysics Data System (ADS)

    Litwin, R. Z.

    2002-03-01

    The Boeing Company fabricated the Solar Two receiver as a subcontractor for the Solar Two project. The receiver absorbed sunlight reflected from the heliostat field. A molten-nitrate-salt heat transfer fluid was pumped from a storage tank at grade level, heated from 290 to 565DGC by the receiver mounted on top of a tower, then flowed back down into another storage tank. To make electricity, the hot salt was pumped through a steam generator to produce steam that powered a conventional Rankine steam turbine/generator. This evaluation identifies the most significant Solar Two receiver system lessons learned from the Mechanical Design, Instrumentation and Control, Panel Fabrication, Site Construction, Receiver System Operation, and Management from the perspective of the receiver designer/manufacturer. The lessons learned on the receiver system described here consist of two parts: the Problem and one or more identified Solutions. The appendix summarizes an inspection of the advanced receiver panel developed by Boeing that was installed and operated in the Solar Two receiver.

  7. Thermal buffering of receivers for parabolic dish solar thermal power plants

    NASA Technical Reports Server (NTRS)

    Manvi, R.; Fujita, T.; Gajanana, B. C.; Marcus, C. J.

    1980-01-01

    A parabolic dish solar thermal power plant comprises a field of parabolic dish power modules where each module is composed of a two-axis tracking parabolic dish concentrator which reflects sunlight (insolation) into the aperture of a cavity receiver at the focal point of the dish. The heat generated by the solar flux entering the receiver is removed by a heat transfer fluid. In the dish power module, this heat is used to drive a small heat engine/generator assembly which is directly connected to the cavity receiver at the focal point. A computer analysis is performed to assess the thermal buffering characteristics of receivers containing sensible and latent heat thermal energy storage. Parametric variations of the thermal inertia of the integrated receiver-buffer storage systems coupled with different fluid flow rate control strategies are carried out to delineate the effect of buffer storage, the transient response of the receiver-storage systems and corresponding fluid outlet temperature. It is concluded that addition of phase change buffer storage will substantially improve system operational characteristics during periods of rapidly fluctuating insolation due to cloud passage.

  8. Overcoming the challenges of BeiDou receiver implementation.

    PubMed

    Bhuiyan, Mohammad Zahidul H; Söderholm, Stefan; Thombre, Sarang; Ruotsalainen, Laura; Kuusniemi, Heidi

    2014-11-21

    Global Navigation Satellite System (GNSS)-based positioning is experiencing rapid changes. The existing GPS and the GLONASS systems are being modernized to better serve the current challenging applications under harsh signal conditions. These modernizations include increasing the number of transmission frequencies and changes to the signal components. In addition, the Chinese BeiDou Navigation Satellite system (BDS) and the European Galileo are currently under development for global operation. Therefore, in view of these new upcoming systems the research and development of GNSS receivers has been experiencing a new upsurge. In this article, the authors discuss the main functionalities of a GNSS receiver in view of BDS. While describing the main functionalities of a software-defined BeiDou receiver, the authors also highlight the similarities and differences between the signal characteristics of the BeiDou B1 open service signal and the legacy GPS L1 C/A signal, as in general they both exhibit similar characteristics. In addition, the authors implement a novel acquisition technique for long coherent integration in the presence of NH code modulation in BeiDou D1 signal. Furthermore, a simple phase-preserved coherent integration based acquisition scheme is implemented for BeiDou GEO satellite acquisition. Apart from the above BeiDou-specific implementations, a novel Carrier-to-Noise-density ratio estimation technique is also implemented in the software receiver, which does not necessarily require bit synchronization prior to estimation. Finally, the authors present a BeiDou-only position fix with the implemented software-defined BeiDou receiver considering all three satellite constellations from BDS. In addition, a true multi-GNSS position fix with GPS and BDS systems is also presented while comparing their performances for a static stand-alone code phase-based positioning.

  9. Overcoming the Challenges of BeiDou Receiver Implementation

    PubMed Central

    Bhuiyan, Mohammad Zahidul H.; Söderholm, Stefan; Thombre, Sarang; Ruotsalainen, Laura; Kuusniemi, Heidi

    2014-01-01

    Global Navigation Satellite System (GNSS)-based positioning is experiencing rapid changes. The existing GPS and the GLONASS systems are being modernized to better serve the current challenging applications under harsh signal conditions. These modernizations include increasing the number of transmission frequencies and changes to the signal components. In addition, the Chinese BeiDou Navigation Satellite system (BDS) and the European Galileo are currently under development for global operation. Therefore, in view of these new upcoming systems the research and development of GNSS receivers has been experiencing a new upsurge. In this article, the authors discuss the main functionalities of a GNSS receiver in view of BDS. While describing the main functionalities of a software-defined BeiDou receiver, the authors also highlight the similarities and differences between the signal characteristics of the BeiDou B1 open service signal and the legacy GPS L1 C/A signal, as in general they both exhibit similar characteristics. In addition, the authors implement a novel acquisition technique for long coherent integration in the presence of NH code modulation in BeiDou D1 signal. Furthermore, a simple phase-preserved coherent integration based acquisition scheme is implemented for BeiDou GEO satellite acquisition. Apart from the above BeiDou-specific implementations, a novel Carrier-to-Noise-density ratio estimation technique is also implemented in the software receiver, which does not necessarily require bit synchronization prior to estimation. Finally, the authors present a BeiDou-only position fix with the implemented software-defined BeiDou receiver considering all three satellite constellations from BDS. In addition, a true multi-GNSS position fix with GPS and BDS systems is also presented while comparing their performances for a static stand-alone code phase-based positioning. PMID:25421735

  10. Cellular response to modulated radiation fields

    NASA Astrophysics Data System (ADS)

    Claridge Mackonis, E.; Suchowerska, N.; Zhang, M.; Ebert, M.; McKenzie, D. R.; Jackson, M.

    2007-09-01

    Cell survival following exposure to spatially modulated beams, as created by intensity-modulated radiotherapy (IMRT), is investigated. In vitro experiments were performed using malignant melanoma cells (MM576) exposed to a therapeutic megavoltage photon beam. We compared cell survival in modulated fields with cell survival in uniform control fields. Three different spatial modulations of the field were used: a control 'uniform' field in which all cells in a flask were uniformly exposed; a 'quarter' field in which 25% of cells at one end of the flask were exposed and a 'striped' field in which 25% of cells were exposed in three parallel stripes. The cell survival in both the shielded and unshielded regions of the modulated fields, as determined by a clonogenic assay, were compared to the cell survival in the uniform field. We have distinguished three ways in which cell survival is influenced by the fate of neighbouring cells. The first of these (type I effect) is the previously reported classical Bystander effect, where cell survival is reduced when communicating with irradiated cells. We find two new types of Bystander effect. The type II effect is an observed increase in cell survival when nearby cells receive a lethal dose. The type III effect is an increase in the survival of cells receiving a high dose of radiation, when nearby cells receive a low dose. These observations of the Bystander effects emphasize the need for improved radiobiological models, which include communicated effects and account for the effects of modulated dose distribution.

  11. SplitRFLab: A MATLAB GUI toolbox for receiver function analysis based on SplitLab

    NASA Astrophysics Data System (ADS)

    Xu, Mijian; Huang, Hui; Huang, Zhouchuan; Wang, Liangshu

    2016-02-01

    We add new modules for receiver function (RF) analysis in SplitLab toolbox, which includes the manual RF analysis module, automatic RF analysis and related quality control modules, and H- k stacking module. The updated toolbox (named SplitRFLab toolbox), especially its automatic RF analysis module, could calculate the RFs quickly and efficiently, which is very useful in RF analysis with huge amount of seismic data. China is now conducting the ChinArray project that plans to deploy thousands of portable stations across Chinese mainland. Our SplitRFLab toolbox may obtain reliable RF results quickly at the first time, which provide essentially new constraint to the crustal and mantle structures.

  12. Design and implementation of the CAPS receiver

    NASA Astrophysics Data System (ADS)

    Hu, Yonghui; Hua, Yu; Hou, Lei; Wei, Jingfa; Wu, Jianfeng

    2009-03-01

    In this paper, based on analyses of the Chinese Area Positioning System (CAPS) satellite (GEO satellite) resources and signal properties, the signal power at the port of the receiver antenna is estimated, and the implementation projects are presented for a switching band C to band L CAPS C/A code receiver integrated with GPS receiver suite and for a CAPS dual frequency P code receiver. A microstrip receiving antenna is designed with high sensitivity and wide beam orientation, the RF front end of the C/A code and P code receivers, and a processor is designed for the navigation baseband. A single frequency CAPS C/A code receiver and a CAPS dual frequency P code receiver are built at the same time. A software process flow is provided, and research on relatively key techniques is also conducted, such as signal searching, code loop and carrier loop algorithms, a height assistant algorithm, a dual frequency difference speed measurement technique, a speed measurement technique using a single frequency source with frequency assistance, and a CAPS time correcting algorithm, according to the design frame of the receiver hardware. Research results show that the static plane positioning accuracy of the CAPS C/A code receiver is 20.5-24.6 m, height accuracy is 1.2-12.8 m, speed measurement accuracy is 0.13-0.3 m/s, dynamic plane positioning accuracy is 24.4 m, height accuracy is 3.0 m, and speed measurement accuracy is 0.24 m/s. In the case of C/A code, the timing accuracy is 200 ns, and it is also shown that the positioning accuracy of the CAPS precise code receiver (1 σ) is 5 m from south to north, and 0.8 m from east to west. Finally, research on positioning accuracy is also conducted.

  13. Supported PV module assembly

    DOEpatents

    Mascolo, Gianluigi; Taggart, David F.; Botkin, Jonathan D.; Edgett, Christopher S.

    2013-10-15

    A supported PV assembly may include a PV module comprising a PV panel and PV module supports including module supports having a support surface supporting the module, a module registration member engaging the PV module to properly position the PV module on the module support, and a mounting element. In some embodiments the PV module registration members engage only the external surfaces of the PV modules at the corners. In some embodiments the assembly includes a wind deflector with ballast secured to a least one of the PV module supports and the wind deflector. An array of the assemblies can be secured to one another at their corners to prevent horizontal separation of the adjacent corners while permitting the PV modules to flex relative to one another so to permit the array of PV modules to follow a contour of the support surface.

  14. Coherent optical modulation for antenna remoting

    NASA Technical Reports Server (NTRS)

    Fitzmartin, D. J.; Gels, R. G.; Balboni, E. J.

    1991-01-01

    A coherent fiber optic link employing wideband frequency modulation (FM) of the optical carrier is used to transfer radio frequency (RF) or microwave signals. This system is used to link a remotely located antenna to a conveniently located electronics processing site. The advantages of coherent analog fiber optic systems over non-coherent intensity modulated fiber optic analog transmission systems are described. An optical FM link employing an indirect transmitter to frequency modulate the optical carrier and a microwave delay line discriminator receiver is described. Measured performance data for a video signal centered at 60 MHz is presented showing the use of wideband FM in the link.

  15. Liquid cooled fiber thermal radiation receiver

    DOEpatents

    Butler, Barry L.

    1987-01-01

    A radiation-to-thermal receiver apparatus for collecting radiation and converting it to thermal energy is disclosed. The invention includes a fibrous mat material which captures radiation striking the receiver. Captured radiation is removed from the fibrous mat material by a transparent fluid within which the material is bathed.

  16. 47 CFR 80.858 - Radiotelephone receiver.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the section must: (1) Have a sensitivity of 50 microvolts; (2) Be capable of operation when energized... showing the name of the receiver manufacturer and the type or model. (d) The sensitivity of a receiver is... of at least 6 decibels. Evidence of a manufacturer's rating or a demonstration of the sensitivity...

  17. Optimization of MLS receivers for multipath environments

    NASA Technical Reports Server (NTRS)

    Mcalpine, G. A.; Highfill, J. H., III; Irwin, S. H.; Padgett, J. E.

    1975-01-01

    A receiver is designed for aircraft (A/C), which, as a component of the proposed Microwave Landing System (MLS), is capable of optimal performance in the multipath environments found in air terminal areas. Topics discussed include: the angle-tracking problem of the MLS receiver; signal modeling; preliminary approaches to optimal design; suboptimal design; and simulation study.

  18. Cashier/Accounts Receivable Clerk Exploration.

    ERIC Educational Resources Information Center

    Portsmouth City School Board, VA.

    The student materials present exercises designed to simulate the job performed by a cashier/accounts receivable clerk. The content of the course covers job instructions, writing receipts, proving cash, customer accounts, preparing statements, and schedule of accounts receivable. Also included in the document are a pretest and post test for the…

  19. Liquid cooled fiber thermal radiation receiver

    DOEpatents

    Butler, B.L.

    1985-03-29

    A radiation-to-thermal receiver apparatus for collecting radiation and converting it to thermal energy is disclosed. The invention includes a fibrous mat material which captures radiation striking the receiver. Captured radiation is removed from the fibrous mat material by a transparent fluid within which the material is bathed.

  20. Advanced heat receiver conceptual design study

    NASA Technical Reports Server (NTRS)

    Kesseli, James; Saunders, Roger; Batchelder, Gary

    1988-01-01

    Solar Dynamic space power systems are candidate electrical power generating systems for future NASA missions. One of the key components of the solar dynamic power system is the solar receiver/thermal energy storage (TES) subsystem. Receiver development was conducted by NASA in the late 1960's and since then a very limited amount of work has been done in this area. Consequently the state of the art (SOA) receivers designed for the IOC space station are large and massive. The objective of the Advanced Heat Receiver Conceptual Design Study is to conceive and analyze advanced high temperature solar dynamic Brayton and Stirling receivers. The goal is to generate innovative receiver concepts that are half of the mass, smaller, and more efficient than the SOA. It is also necessary that these innovative receivers offer ease of manufacturing, less structural complexity and fewer thermal stress problems. Advanced Brayton and Stirling receiver storage units are proposed and analyzed in this study which can potentially meet these goals.

  1. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Television receivers. 1020.10 Section 1020.10 Food...) RADIOLOGICAL HEALTH PERFORMANCE STANDARDS FOR IONIZING RADIATION EMITTING PRODUCTS § 1020.10 Television receivers. (a) Applicability. The provisions of this section are applicable to television...

  2. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Television receivers. 1020.10 Section 1020.10 Food...) RADIOLOGICAL HEALTH PERFORMANCE STANDARDS FOR IONIZING RADIATION EMITTING PRODUCTS § 1020.10 Television receivers. (a) Applicability. The provisions of this section are applicable to television...

  3. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Television receivers. 1020.10 Section 1020.10 Food...) RADIOLOGICAL HEALTH PERFORMANCE STANDARDS FOR IONIZING RADIATION EMITTING PRODUCTS § 1020.10 Television receivers. (a) Applicability. The provisions of this section are applicable to television...

  4. 7 CFR 966.124 - Approved receiver.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Rules and..., as an approved receiver, tomatoes for purposes as set forth in § 966.120(a), shall annually, prior... specified purpose is to occur; (4) Whether or not the receiver packs, repacks or sells fresh tomatoes; (5)...

  5. 47 CFR 80.961 - Radiotelephone receiver.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Radiotelephone receiver. 80.961 Section 80.961... MARITIME SERVICES Radiotelephone Installation Required for Vessels on the Great Lakes § 80.961... frequencies. (b) The receiver must have a sensitivity of at least 2 microvolts across 50 ohms for a 20...

  6. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) RADIOLOGICAL HEALTH PERFORMANCE STANDARDS FOR IONIZING RADIATION EMITTING PRODUCTS § 1020.10 Television... volts if the receiver is designed to operate from nominal 110 to 120 root mean square volt power sources. If the receiver is designed to operate from a power source having some voltage other than...

  7. Direct-conversion receiver for HiperLAN2

    NASA Astrophysics Data System (ADS)

    Gu, Jian

    2001-11-01

    A direct conversion receiver is presented for HiperLAN2 system that uses Orthogonal Frequency Division Multiplexing (OFDM) as its modulation scheme with data rate up to 54 Mbits/second. The direct conversion scheme converts the RF signal directly into a complex low-pass equivalent signal represented by in- phase (I) and quadrature (Q) components or so called I-Q base- band signal without any Intermediate Frequency (IF) stages and expensive Surface-Acoustic-Wave (SAW) filters. However, for a direct conversion receiver there are many key issues to be solved. One of the most important issues is so-called I-Q imbalance caused by the mismatch between I channel and Q channel of the quadrature demodulator. The I-Q imbalance may include gain and group delay difference between the I channel and the Q channel at any frequency within the low-pass signal bandwidth. With the patent-pending IQ-BalancingTM technology and other proprietary technologies of 4D Connect, inc., the adverse effects of I-Q imbalance on the receiver performance can be removed. Fixed-point simulation results for sensitivity performance and interference performance are presented. Performance comparisons when severe I-Q imbalance is present are also given.

  8. Going Up. A GPS Receiver Adapts to Space

    NASA Technical Reports Server (NTRS)

    Lightsey, E. Glenn; Simpson, James E.

    2000-01-01

    Current plans for the space station call for the GPS receiver to be installed on the U.S. lab module of the station in early 2001 (ISS Assembly Flight SA), followed by the attachment of the antenna array in late 2001 (Flight 8A). At that point the U.S. ISS guidance and control system will be operational. The flight of SIGI on the space station represents a "coming of age" for GPS technology on spacecraft. For at least a decade, the promise of using GPS receivers to automate spacecraft operations, simplify satellite design, and reduce mission costs has enticed satellite designers. Integration of this technology onto spacecraft has been slower than some originally anticipated. However, given the complexity of the GPS sensor, and the importance of the functions it performs, its incorporation into mainstream satellite design has probably occurred at a very reasonable pace. Going from providing experimental payloads on small, unmanned satellites to performing critical operational functions on manned vehicles has been a major evolution. If all goes as planned in the next few months, GPS receivers will soon provide those critical functions on one of the most complex spacecraft in history, the International Space Station.

  9. Directional Receiver for Biomimetic Sonar System

    NASA Astrophysics Data System (ADS)

    Guarato, Francesco; Andrews, Heather; Windmill, James F.; Jackson, Joseph; Gachagan, Anthony

    An ultrasonic localization method for a sonar system equipped with an emitter and two directional receivers and inspired by bat echolocation uses knowledge of the beam pattern of the receivers to estimate target orientation. Rousettus leschenaultii's left ear constitutes the model for the design of the optimal receiver for this sonar system and 3D printing was used to fabricate receiver structures comprising of two truncated cones with an elliptical external perimeter and a parabolic flare rate in the upper part. Measurements show one receiver has a predominant lobe in the same region and with similar attenuation values as the bat ear model. The final sonar system is to be mounted on vehicular and aerial robots which require remote control for motion and sensors for estimation of each robot's location.

  10. EHF low-noise FET receiver

    NASA Technical Reports Server (NTRS)

    Schellenberg, J. M.; Watkins, E. T.

    1983-01-01

    Extremely high frequency (EHF) receivers for military and NASA programs must be small, lightweight, and highly reliable. In connection with recent advances in the development of mm-wave FET devices and circuits, a basis has been obtained for the eventual replacement of diode mixer front-ends by FET preamplifiers in receivers up to 94 GHz. By placing a low noise amplifier in front of the mixer it is possible to achieve a lower system noise figure than that found in conventional mm-wave receivers. A broader bandwidth can also be provided. Attention is given to the receiver configuration, a low noise FET amplifier, an image rejection filter, a dual-gate FET mixer, a FET local oscillator, and a FET receiver.

  11. Avoiding potential problems when selling accounts receivable.

    PubMed

    Ayers, D H; Kincaid, T J

    1996-05-01

    Accounts receivable financing is a potential tool for managing a provider organization's working capital needs. But before entering into a financing agreement, organizations need to consider and take steps to avoid serious problems that can arise from participation in an accounts receivable financing program. For example, the purchaser may cease purchasing the receivables, leaving the organization without funding needed for operations. Or, the financing program may be inordinately complex and unnecessarily costly to the organization. Sometimes the organization itself may fail to comply with the terms of the agreement under which the accounts receivable were sold, thus necessitating that restitution be made to the purchaser or provoking charges of fraud. These potential problems should be addressed as early as possible--before an organization enters into an accounts receivable financing program--in order to minimize time, effort, and expanse and maximize the benefits of the financing agreement.

  12. High dynamic, low volume GPS receiver

    NASA Technical Reports Server (NTRS)

    Hurd, W. J.

    1983-01-01

    A new GPS receiver concept and design are presented to meet the high dynamic and low volume requirements for range applications in missiles and drones. The receiver has the potential to satisfy all range requirements with one basic receiver, which has significant potential economic benefit over the alternate approach of using a family of receivers, each tailored for specific applications. The main new concept is to use approximate maximum likelihood estimates of pseudo range and range-rate, rather than tracking with carrier phase locked loops and code delay locked loops. Preliminary analysis indicates that receivers accelerating at 50 g or more can track with position errors due to acceleration of approximately 0.2 m/g, or 10 m at 50 g. Implementation is almost entirely digital to meet the low volume requirements.

  13. Carrier Modulation Via Waveform Probability Density Function

    NASA Technical Reports Server (NTRS)

    Williams, Glenn L.

    2006-01-01

    Beyond the classic modes of carrier modulation by varying amplitude (AM), phase (PM), or frequency (FM), we extend the modulation domain of an analog carrier signal to include a class of general modulations which are distinguished by their probability density function histogram. Separate waveform states are easily created by varying the pdf of the transmitted waveform. Individual waveform states are assignable as proxies for digital one's or zero's. At the receiver, these states are easily detected by accumulating sampled waveform statistics and performing periodic pattern matching, correlation, or statistical filtering. No fundamental physical laws are broken in the detection process. We show how a typical modulation scheme would work in the digital domain and suggest how to build an analog version. We propose that clever variations of the modulating waveform (and thus the histogram) can provide simple steganographic encoding.

  14. Carrier Modulation Via Waveform Probability Density Function

    NASA Technical Reports Server (NTRS)

    Williams, Glenn L.

    2004-01-01

    Beyond the classic modes of carrier modulation by varying amplitude (AM), phase (PM), or frequency (FM), we extend the modulation domain of an analog carrier signal to include a class of general modulations which are distinguished by their probability density function histogram. Separate waveform states are easily created by varying the pdf of the transmitted waveform. Individual waveform states are assignable as proxies for digital ONEs or ZEROs. At the receiver, these states are easily detected by accumulating sampled waveform statistics and performing periodic pattern matching, correlation, or statistical filtering. No fundamental natural laws are broken in the detection process. We show how a typical modulation scheme would work in the digital domain and suggest how to build an analog version. We propose that clever variations of the modulating waveform (and thus the histogram) can provide simple steganographic encoding.

  15. UHF FM receiver having improved frequency stability and low RFI emission

    DOEpatents

    Lupinetti, Francesco

    1990-02-27

    A UHF receiver which converts UHF modulated carrier signals to baseband video signals without any heterodyne or frequency conversion stages. A bandpass filter having a fixed frequency first filters the signals. A low noise amplifier amplifies the filtered signal and applies the signal through further amplification stages to a limited FM demodulator circuit. The UHF signal is directly converted to a baseband video signal. The baseband video signal is clamped by a clamping circuit before driving a monitor. Frequency stability for the receivers is at a theoretical maximum, and interference to adjacent receivers is eliminated due to the absence of a local oscillator.

  16. Reduction of Phase Ambiguity in an Offset-QPSK Receiver

    NASA Technical Reports Server (NTRS)

    Berner, Jeff; Kinman, Peter

    2004-01-01

    Proposed modifications of an offset-quadri-phase-shift keying (offset-QPSK) transmitter and receiver would reduce the amount of signal processing that must be done in the receiver to resolve the QPSK fourfold phase ambiguity. Resolution of the phase ambiguity is necessary in order to synchronize, with the received carrier signal, the signal generated by a local oscillator in a carrier-tracking loop in the receiver. Without resolution of the fourfold phase ambiguity, the loop could lock to any of four possible phase points, only one of which has the proper phase relationship with the carrier. The proposal applies, more specifically, to an offset-QPSK receiver that contains a carrier-tracking loop like that shown in Figure 1. This carrier-tracking loop does not resolve or reduce the phase ambiguity. A carrier-tracking loop of a different design optimized for the reception of offset QPSK could reduce the phase ambiguity from fourfold to twofold, but would be more complex. Alternatively, one could resolve the fourfold phase ambiguity by use of differential coding in the transmitter, at a cost of reduced power efficiency. The proposed modifications would make it possible to reduce the fourfold phase ambiguity to twofold, with no loss in power efficiency and only relatively simple additional signal-processing steps in the transmitter and receiver. The twofold phase ambiguity would then be resolved by use of a unique synchronization word, as is commonly done in binary phase-shift keying (BPSK). Although the mathematical and signal-processing principles underlying the modifications are too complex to explain in detail here, the modifications themselves would be relatively simple and are best described with the help of simple block diagrams (see Figure 2). In the transmitter, one would add a unit that would periodically invert bits going into the QPSK modulator; in the receiver, one would add a unit that would effect different but corresponding inversions of bits coming out

  17. Wide-Band Microwave Receivers Using Photonic Processing

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey; Maleki, Lute; Itchenko, Vladimir; Yu, Nan; Strekalov, Dmitry; Savchenkov, Anatoliy

    2008-01-01

    In wide-band microwave receivers of a type now undergoing development, the incoming microwave signals are electronically preamplified, then frequency-up-converted to optical signals that are processed photonically before being detected. This approach differs from the traditional approach, in which incoming microwave signals are processed by purely electronic means. As used here, wide-band microwave receivers refers especially to receivers capable of reception at any frequency throughout the range from about 90 to about 300 GHz. The advantage expected to be gained by following the up-conversion-and-photonic-processing approach is the ability to overcome the limitations of currently available detectors and tunable local oscillators in the frequency range of interest. In a receiver following this approach (see figure), a preamplified incoming microwave signal is up-converted by the method described in the preceeding article. The frequency up-converter exploits the nonlinearity of the electromagnetic response of a whispering gallery mode (WGM) resonator made of LiNbO3. Up-conversion takes place by three-wave mixing in the resonator. The WGM resonator is designed and fabricated to function simultaneously as an electro-optical modulator and to exhibit resonance at the microwave and optical operating frequencies plus phase matching among the microwave and optical signals circulating in the resonator. The up-conversion is an efficient process, and the efficiency is enhanced by the combination of microwave and optical resonances. The up-converted signal is processed photonically by use of a tunable optical filter or local oscillator, and is then detected. Tunable optical filters can be made to be frequency agile and to exhibit high resonance quality factors (high Q values), thereby making it possible to utilize a variety of signal-processing modalities. Therefore, it is anticipated that when fully developed, receivers of this type will be compact and will be capable of both

  18. Lunar Module Ascent Stage

    NASA Technical Reports Server (NTRS)

    1969-01-01

    The Lunar Module 'Spider' ascent stage is photographed from the Command/Service Module on the fifth day of the Apollo 9 earth-orbital mission. The Lunar Module's descent stage had already been jettisoned.

  19. Wide deviation phase modulator

    NASA Technical Reports Server (NTRS)

    Couch, R. H.; Hearn, C. P.; Wilson, L. R.

    1974-01-01

    Modulator produces phase-modulated waveform having high modulating linearity. Technique is inherently wideband with respect to carrier frequency and can operate over decade carrier frequency range without adjustments. Circuit performance is both mathematically predictable and highly reproducible.

  20. Enhanced AIS receiver design for satellite reception

    NASA Astrophysics Data System (ADS)

    Clazzer, Federico; Lázaro, Francisco; Plass, Simon

    2016-12-01

    The possibility to detect Automatic Identification System (AIS) messages from low earth orbit (LEO) satellites paves the road for a plurality of new and unexplored services. Besides worldwide tracking of vessels, maritime traffic monitoring, analysis of vessel routes employing big data, and oceans monitoring are just few of the fields, where satellite-aided AIS is beneficial. Designed for ship-to-ship communication and collision avoidance, AIS satellite reception performs poorly in regions with a high density of vessels. This calls for the development of advanced satellite AIS receivers able to improve the decoding capabilities. In this context, our contribution focuses on the introduction of a new enhanced AIS receiver design and its performance evaluation. The enhanced receiver makes use of a coherent receiver for the low signal-to-noise ratio (SNR) region, while for medium to high SNRs, a differential Viterbi receiver is used. Additional novelty of our work is in the exploitation of previously decoded packets from one vessel that is still under the LEO reception range, to improve the vessel detection probability. The assessment of the performance against a common receiver is done making the use of a simple and tight model of the medium access (MAC) layer and the multi-packet reception (MPR) matrix for physical layer (PHY) representation. Performance results show the benefits of such enhanced receiver, especially when it is bundled with successive interference cancellation (SIC).

  1. Terahertz Array Receivers with Integrated Antennas

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Goutam; Llombart, Nuria; Lee, Choonsup; Jung, Cecile; Lin, Robert; Cooper, Ken B.; Reck, Theodore; Siles, Jose; Schlecht, Erich; Peralta, Alessandro; Thomas, Bertrand; Mehdi, Imran

    2011-01-01

    Highly sensitive terahertz heterodyne receivers have been mostly single-pixel. However, now there is a real need of multi-pixel array receivers at these frequencies driven by the science and instrument requirements. In this paper we explore various receiver font-end and antenna architectures for use in multi-pixel integrated arrays at terahertz frequencies. Development of wafer-level integrated terahertz receiver front-end by using advanced semiconductor fabrication technologies has progressed very well over the past few years. Novel stacking of micro-machined silicon wafers which allows for the 3-dimensional integration of various terahertz receiver components in extremely small packages has made it possible to design multi-pixel heterodyne arrays. One of the critical technologies to achieve fully integrated system is the antenna arrays compatible with the receiver array architecture. In this paper we explore different receiver and antenna architectures for multi-pixel heterodyne and direct detector arrays for various applications such as multi-pixel high resolution spectrometer and imaging radar at terahertz frequencies.

  2. Temperature influences in receiver clock modelling

    NASA Astrophysics Data System (ADS)

    Wang, Kan; Meindl, Michael; Rothacher, Markus; Schoenemann, Erik; Enderle, Werner

    2016-04-01

    In Precise Point Positioning (PPP), hardware delays at the receiver site (receiver, cables, antenna, …) are always difficult to be separated from the estimated receiver clock parameters. As a result, they are partially or fully contained in the estimated "apparent" clocks and will influence the deterministic and stochastic modelling of the receiver clock behaviour. In this contribution, using three years of data, the receiver clock corrections of a set of high-precision Hydrogen Masers (H-Masers) connected to stations of the ESA/ESOC network and the International GNSS Service (IGS) are firstly characterized concerning clock offsets, drifts, modified Allan deviations and stochastic parameters. In a second step, the apparent behaviour of the clocks is modelled with the help of a low-order polynomial and a known temperature coefficient (Weinbach, 2013). The correlations between the temperature and the hardware delays generated by different types of antennae are then analysed looking at daily, 3-day and weekly time intervals. The outcome of these analyses is crucial, if we intend to model the receiver clocks in the ground station network to improve the estimation of station-related parameters like coordinates, troposphere zenith delays and ambiguities. References: Weinbach, U. (2013) Feasibility and impact of receiver clock modeling in precise GPS data analysis. Dissertation, Leibniz Universität Hannover, Germany.

  3. The Los Alamos beacon receiver array

    SciTech Connect

    Carlos, R.C.; Massey, R.S. )

    1994-07-01

    The authors are interested in studying both the natural background of acoustic and acoustic-gravity waves, for which the sources are not generally known, as well as waves produced by known sources such as large explosions and launches of large rockets. The authors describe radio receivers that monitor transmissions from beacons on geosynchronous satellites. The receivers can detect perturbations of a 300--3,000 s period in the electron density integrated from beacon to receiver, for amplitudes as low as (1--2) [times] 10[sup 13] m[sup [minus]2]. Data are used in studies of atmospheric acoustic and acoustic-gravity waves.

  4. Global Positioning System receiver evaluation results

    SciTech Connect

    Byrne, R.H.

    1993-09-01

    A Sandia project currently uses an outdated Magnavox 6400 Global Positioning System (GPS) receiver as the core of its navigation system. The goal of this study was to analyze the performance of the current GPS receiver compared to newer, less expensive models and to make recommendations on how to improve the performance of the overall navigation system. This paper discusses the test methodology used to experimentally analyze the performance of different GPS receivers, the test results, and recommendations on how an upgrade should proceed. Appendices contain detailed information regarding the raw data, test hardware, and test software.

  5. Amplitude-modulation detection by gerbils in reverberant sound fields.

    PubMed

    Lingner, Andrea; Kugler, Kathrin; Grothe, Benedikt; Wiegrebe, Lutz

    2013-08-01

    Reverberation can dramatically reduce the depth of amplitude modulations which are critical for speech intelligibility. Psychophysical experiments indicate that humans' sensitivity to amplitude modulation in reverberation is better than predicted from the acoustic modulation depth at the receiver position. Electrophysiological studies on reverberation in rabbits highlight the contribution of neurons sensitive to interaural correlation. Here, we use a prepulse-inhibition paradigm to quantify the gerbils' amplitude modulation threshold in both anechoic and reverberant virtual environments. Data show that prepulse inhibition provides a reliable method for determining the gerbils' AM sensitivity. However, we find no evidence for perceptual restoration of amplitude modulation in reverberation. Instead, the deterioration of AM sensitivity in reverberant conditions can be quantitatively explained by the reduced modulation depth at the receiver position. We suggest that the lack of perceptual restoration is related to physical properties of the gerbil's ear input signals and inner-ear processing as opposed to shortcomings of their binaural neural processing.

  6. Collector/Receiver Characterization (Fact Sheet)

    SciTech Connect

    Not Available

    2010-08-01

    Fact sheet describing NREL CSP Program capabilities for collector/receiver characterization: determining optical efficiency, measuring heat loss, developing and testing concentrators, concentrating the sun's power, and optically characterizing CSP plants.

  7. Go International! Build a Simplified Shortwave Receiver

    ERIC Educational Resources Information Center

    Homoly, Clarke

    2008-01-01

    This article presents a plan for building a shortwave receiver that is doable, educational and has reasonable performance. The project, says the author, can give students years of listening fun without a major financial investment. Potential project improvements are included.

  8. 47 CFR 80.913 - Radiotelephone receivers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... public coast stations serving the area in which the vessel is navigated. (d) One or more loudspeakers... at the receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a...

  9. 47 CFR 80.858 - Radiotelephone receiver.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... frequencies authorized pursuant to § 80.855(a). (b) One or more loudspeakers capable of being used to maintain... receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to-noise...

  10. 47 CFR 80.858 - Radiotelephone receiver.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... frequencies authorized pursuant to § 80.855(a). (b) One or more loudspeakers capable of being used to maintain... receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to-noise...

  11. 47 CFR 80.858 - Radiotelephone receiver.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... frequencies authorized pursuant to § 80.855(a). (b) One or more loudspeakers capable of being used to maintain... receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to-noise...

  12. 47 CFR 80.913 - Radiotelephone receivers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... public coast stations serving the area in which the vessel is navigated. (d) One or more loudspeakers... at the receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a...

  13. 47 CFR 80.913 - Radiotelephone receivers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... public coast stations serving the area in which the vessel is navigated. (d) One or more loudspeakers... at the receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a...

  14. 47 CFR 80.858 - Radiotelephone receiver.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... frequencies authorized pursuant to § 80.855(a). (b) One or more loudspeakers capable of being used to maintain... receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to-noise...

  15. 47 CFR 80.913 - Radiotelephone receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... public coast stations serving the area in which the vessel is navigated. (d) One or more loudspeakers... at the receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a...

  16. Stanley receives 2010 William Gilbert Award: Response

    NASA Astrophysics Data System (ADS)

    Stanley, Sabine

    2011-06-01

    Sabine Stanley received the William Gilbert Award at the 2010 AGU Fall Meeting, held 13-17 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  17. Dennis Kent Receives 2009 William Gilbert Award

    NASA Astrophysics Data System (ADS)

    Tauxe, Lisa; Kent, Dennis

    2010-06-01

    Dennis Kent received the William Gilbert Award at the 2009 AGU Fall Meeting, held 14-18 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  18. Kirschvink receives 2011 William Gilbert Award: Response

    NASA Astrophysics Data System (ADS)

    Kirschvink, Joseph L.

    2012-04-01

    Joseph Kirschvink received the William Gilbert Award at the 2011 AGU Fall Meeting, held 5-9 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  19. Stanley receives 2010 William Gilbert Award: Citation

    NASA Astrophysics Data System (ADS)

    Weiss, Benjamin P.

    2011-06-01

    Sabine Stanley received the William Gilbert Award at the 2010 AGU Fall Meeting, held 13-17 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  20. Lagroix Receives 2008 William Gilbert Award

    NASA Astrophysics Data System (ADS)

    Moskowitz, Bruce M.; Banerjee, Subir K.; Lagroix, France

    2009-04-01

    France Lagroix received the William Gilbert Award at the 2008 AGU Fall Meeting Honors Ceremony, held 17 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  1. Kirschvink receives 2011 William Gilbert Award: Citation

    NASA Astrophysics Data System (ADS)

    Weiss, Benjamin P.

    2012-04-01

    Joseph Kirschvink received the William Gilbert Award at the 2011 AGU Fall Meeting, held 5-9 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  2. Beacon satellite receiver for ionospheric tomography

    NASA Astrophysics Data System (ADS)

    Vierinen, J.; Norberg, J.; Lehtinen, M. S.; Amm, O.; Roininen, L.; Väänänen, A.; Erickson, P. J.; McKay-Bukowski, D.

    2014-12-01

    We introduce a new coherent dual-channel beacon satellite receiver intended for ionospheric tomography. The measurement equation includes neutral atmosphere and ionosphere propagation effects, relative errors in satellite and receiver clocks, and residual Doppler shifts caused by errors in the satellite ephemeris. We also investigate the distribution of errors for phase curve measurements and the use of phase curve measurements for limited angle tomography using the framework of statistical linear inverse problems. We describe the design of our beacon satellite receiver software and present one possible hardware configuration. Finally, we present results obtained using a network of four newly developed receivers and compare the results with those of an existing ionospheric tomography network at Sodankylä Geophysical Observatory.

  3. Absentee Ballot Track, Receive, and Confirm Act

    THOMAS, 111th Congress

    Rep. Davis, Susan A. [D-CA-53

    2009-05-20

    08/03/2009 Received in the Senate and Read twice and referred to the Committee on Rules and Administration. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

  4. NASA Dryden Receives 'New' F-15Ds

    NASA Video Gallery

    NASA's Dryden Flight Research Center has received three F-15D Eagle aircraft from the U.S. Air Force for flight research and mission support duties. The demilitarized high-performance aircraft were...

  5. 29 CFR 1910.169 - Air receivers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and... therein are easily accessible. Under no circumstances shall an air receiver be buried underground...

  6. 29 CFR 1910.169 - Air receivers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and... therein are easily accessible. Under no circumstances shall an air receiver be buried underground...

  7. 29 CFR 1926.306 - Air receivers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... transportation vehicles such as steam railroad cars, electric railway cars, and automotive equipment. (2) New and... manholes therein are easily accessible. Under no circumstances shall an air receiver be buried...

  8. High dynamic GPS receiver validation demonstration

    NASA Technical Reports Server (NTRS)

    Hurd, W. J.; Statman, J. I.; Vilnrotter, V. A.

    1985-01-01

    The Validation Demonstration establishes that the high dynamic Global Positioning System (GPS) receiver concept developed at JPL meets the dynamic tracking requirements for range instrumentation of missiles and drones. It was demonstrated that the receiver can track the pseudorange and pseudorange rate of vehicles with acceleration in excess of 100 g and jerk in excess of 100 g/s, dynamics ten times more severe than specified for conventional High Dynamic GPS receivers. These results and analytic extensions to a complete system configuration establish that all range instrumentation requirements can be met. The receiver can be implemented in the 100 cu in volume required by all missiles and drones, and is ideally suited for transdigitizer or translator applications.

  9. Embedded neural recording with TinyOS-based wireless-enabled processor modules.

    PubMed

    Farshchi, Shahin; Pesterev, Aleksey; Nuyujukian, Paul; Guenterberg, Eric; Mody, Istvan; Judy, Jack W

    2010-04-01

    To create a wireless neural recording system that can benefit from the continuous advancements being made in embedded microcontroller and communications technologies, an embedded-system-based architecture for wireless neural recording has been designed, fabricated, and tested. The system consists of commercial-off-the-shelf wireless-enabled processor modules (motes) for communicating the neural signals, and a back-end database server and client application for archiving and browsing the neural signals. A neural-signal-acquisition application has been developed to enable the mote to either acquire neural signals at a rate of 4000 12-bit samples per second, or detect and transmit spike heights and widths sampled at a rate of 16670 12-bit samples per second on a single channel. The motes acquire neural signals via a custom low-noise neural-signal amplifier with adjustable gain and high-pass corner frequency that has been designed, and fabricated in a 1.5-microm CMOS process. In addition to browsing acquired neural data, the client application enables the user to remotely toggle modes of operation (real-time or spike-only), as well as amplifier gain and high-pass corner frequency.

  10. Single-Receiver GPS Phase Bias Resolution

    NASA Technical Reports Server (NTRS)

    Bertiger, William I.; Haines, Bruce J.; Weiss, Jan P.; Harvey, Nathaniel E.

    2010-01-01

    Existing software has been modified to yield the benefits of integer fixed double-differenced GPS-phased ambiguities when processing data from a single GPS receiver with no access to any other GPS receiver data. When the double-differenced combination of phase biases can be fixed reliably, a significant improvement in solution accuracy is obtained. This innovation uses a large global set of GPS receivers (40 to 80 receivers) to solve for the GPS satellite orbits and clocks (along with any other parameters). In this process, integer ambiguities are fixed and information on the ambiguity constraints is saved. For each GPS transmitter/receiver pair, the process saves the arc start and stop times, the wide-lane average value for the arc, the standard deviation of the wide lane, and the dual-frequency phase bias after bias fixing for the arc. The second step of the process uses the orbit and clock information, the bias information from the global solution, and only data from the single receiver to resolve double-differenced phase combinations. It is called "resolved" instead of "fixed" because constraints are introduced into the problem with a finite data weight to better account for possible errors. A receiver in orbit has much shorter continuous passes of data than a receiver fixed to the Earth. The method has parameters to account for this. In particular, differences in drifting wide-lane values must be handled differently. The first step of the process is automated, using two JPL software sets, Longarc and Gipsy-Oasis. The resulting orbit/clock and bias information files are posted on anonymous ftp for use by any licensed Gipsy-Oasis user. The second step is implemented in the Gipsy-Oasis executable, gd2p.pl, which automates the entire process, including fetching the information from anonymous ftp

  11. A handbook for solar central receiver design

    SciTech Connect

    Falcone, P.K.

    1986-12-01

    This Handbook describes central receiver technology for solar thermal power plants. It contains a description and assessment of the major components in a central receiver system configured for utility scale production of electricity using Rankine-cycle steam turbines. It also describes procedures to size and optimize a plant and discussed examples from recent system analyses. Information concerning site selection criteria, cost estimation, construction, and operation and maintenance is also included, which should enable readers to perform design analyses for specific applications.

  12. Optimization of Passive Coherent Receiver System Placement

    DTIC Science & Technology

    2013-09-01

    the transmitter location. The difference between mono and bistatic radars is depicted in Figure 1. This change in antenna placement can help negate...requirements of traditional mono -static radar systems. Although there are benefits associated with the use of these NMR systems, additional challenges arise...applications of mono -static radar systems since the received signal is expected to return to the receiver from the same direction the originating signal

  13. Flexible receiver adapter formal design review

    SciTech Connect

    Krieg, S.A.

    1995-06-13

    This memo summarizes the results of the Formal (90%) Design Review process and meetings held to evaluate the design of the Flexible Receiver Adapters, support platforms, and associated equipment. The equipment is part of the Flexible Receiver System used to remove, transport, and store long length contaminated equipment and components from both the double and single-shell underground storage tanks at the 200 area tank farms.

  14. Digital time slot display for Omega receiver

    NASA Technical Reports Server (NTRS)

    Smith, R. E.

    1976-01-01

    Methods of decoding a digital word to display alpha-numeric characters for driving a standard seven-segment LED display have been devised for Omega station identification. The circuit could replace the system now being used in Ohio University's Omega receivers, which lights one of eight LED's to signify the Omega time slot being received. The letters A through H, representing the Omega stations, can be read directly from the seven-segment display.

  15. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Scanning receivers and frequency converters used with scanning receivers. 15.121 Section 15.121 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.121 Scanning receivers and...

  16. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Scanning receivers and frequency converters used with scanning receivers. 15.121 Section 15.121 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.121 Scanning receivers and...

  17. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Scanning receivers and frequency converters used with scanning receivers. 15.121 Section 15.121 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.121 Scanning receivers and...

  18. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Scanning receivers and frequency converters used with scanning receivers. 15.121 Section 15.121 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.121 Scanning receivers and...

  19. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Scanning receivers and frequency converters used with scanning receivers. 15.121 Section 15.121 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.121 Scanning receivers and...

  20. Comparing Drug Use between Welfare-Receiving Arrestees and Non-Welfare-Receiving Arrestees.

    ERIC Educational Resources Information Center

    Yacoubian, George S., Jr.; Peters, Ronald J., Jr.; Urbach, Blake J.; Johnson, Regina J.

    2002-01-01

    Compares drug-positive rates between welfare-receiving arrestees, non-welfare receiving arrestees living below the poverty level, and non-welfare arrestees living above the poverty level. Welfare-receiving arrestees were more likely to be female, older, less educated, and to test positive for opiates and benzodiazepines than the other subgroups.…

  1. Ballasted photovoltaic module and module arrays

    DOEpatents

    Botkin, Jonathan [El Cerrito, CA; Graves, Simon [Berkeley, CA; Danning, Matt [Oakland, CA

    2011-11-29

    A photovoltaic (PV) module assembly including a PV module and a ballast tray. The PV module includes a PV device and a frame. A PV laminate is assembled to the frame, and the frame includes an arm. The ballast tray is adapted for containing ballast and is removably associated with the PV module in a ballasting state where the tray is vertically under the PV laminate and vertically over the arm to impede overt displacement of the PV module. The PV module assembly can be installed to a flat commercial rooftop, with the PV module and the ballast tray both resting upon the rooftop. In some embodiments, the ballasting state includes corresponding surfaces of the arm and the tray being spaced from one another under normal (low or no wind) conditions, such that the frame is not continuously subjected to a weight of the tray.

  2. Adaptive Detector Arrays for Optical Communications Receivers

    NASA Technical Reports Server (NTRS)

    Vilnrotter, V.; Srinivasan, M.

    2000-01-01

    The structure of an optimal adaptive array receiver for ground-based optical communications is described and its performance investigated. Kolmogorov phase screen simulations are used to model the sample functions of the focal-plane signal distribution due to turbulence and to generate realistic spatial distributions of the received optical field. This novel array detector concept reduces interference from background radiation by effectively assigning higher confidence levels at each instant of time to those detector elements that contain significant signal energy and suppressing those that do not. A simpler suboptimum structure that replaces the continuous weighting function of the optimal receiver by a hard decision on the selection of the signal detector elements also is described and evaluated. Approximations and bounds to the error probability are derived and compared with the exact calculations and receiver simulation results. It is shown that, for photon-counting receivers observing Poisson-distributed signals, performance improvements of approximately 5 dB can be obtained over conventional single-detector photon-counting receivers, when operating in high background environments.

  3. Efficient receiver tuning using differential evolution strategies

    NASA Astrophysics Data System (ADS)

    Wheeler, Caleb H.; Toland, Trevor G.

    2016-08-01

    Differential evolution (DE) is a powerful and computationally inexpensive optimization strategy that can be used to search an entire parameter space or to converge quickly on a solution. The Kilopixel Array Pathfinder Project (KAPPa) is a heterodyne receiver system delivering 5 GHz of instantaneous bandwidth in the tuning range of 645-695 GHz. The fully automated KAPPa receiver test system finds optimal receiver tuning using performance feedback and DE. We present an adaptation of DE for use in rapid receiver characterization. The KAPPa DE algorithm is written in Python 2.7 and is fully integrated with the KAPPa instrument control, data processing, and visualization code. KAPPa develops the technologies needed to realize heterodyne focal plane arrays containing 1000 pixels. Finding optimal receiver tuning by investigating large parameter spaces is one of many challenges facing the characterization phase of KAPPa. This is a difficult task via by-hand techniques. Characterizing or tuning in an automated fashion without need for human intervention is desirable for future large scale arrays. While many optimization strategies exist, DE is ideal for time and performance constraints because it can be set to converge to a solution rapidly with minimal computational overhead. We discuss how DE is utilized in the KAPPa system and discuss its performance and look toward the future of 1000 pixel array receivers and consider how the KAPPa DE system might be applied.

  4. Assembly of opto-electronic module with improved heat sink

    DOEpatents

    Chan, Benson; Fortier, Paul Francis; Freitag, Ladd William; Galli, Gary T.; Guindon, Francois; Johnson, Glen Walden; Letourneau, Martial; Sherman, John H.; Tetreault, Real

    2004-11-23

    A heat sink for a transceiver optoelectronic module including dual direct heat paths and a structure which encloses a number of chips having a central web which electrically isolates transmitter and receiver chips from each other. A retainer for an optical coupler having a port into which epoxy is poured. An overmolded base for an optoelectronic module having epoxy flow controller members built thereon. Assembly methods for an optoelectronic module including gap setting and variation of a TAB bonding process.

  5. Interior view, Array Room, transmitterreceiver modules, left to right, middle ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, Array Room, transmitter-receiver modules, left to right, middle ground. Sub-array drive modules mounted on girders. Array module power supply equipment on floor in foreground, left to right. - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Techinical Equipment Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  6. Quantum memory receiver for superadditive communication using binary coherent states

    PubMed Central

    Klimek, Aleksandra; Jachura, Michał; Wasilewski, Wojciech; Banaszek, Konrad

    2016-01-01

    We propose a simple architecture based on multimode quantum memories for collective readout of classical information keyed using a pair coherent states, exemplified by the well-known binary phase shift keying format. Such a configuration enables demonstration of the superadditivity effect in classical communication over quantum channels, where the transmission rate becomes enhanced through joint detection applied to multiple channel uses. The proposed scheme relies on the recently introduced idea to prepare Hadamard sequences of input symbols that are mapped by a linear optical transformation onto the pulse position modulation format [Guha, S. Phys. Rev. Lett. 2011, 106, 240502]. We analyze two versions of readout based on direct detection and an optional Dolinar receiver which implements the minimum-error measurement for individual detection of a binary coherent state alphabet. PMID:27695200

  7. Multiphase Hadamard receivers for classical communication on lossy bosonic channels

    NASA Astrophysics Data System (ADS)

    Rosati, Matteo; Mari, Andrea; Giovannetti, Vittorio

    2016-12-01

    A scheme for transferring classical information over a lossy bosonic channel is proposed by generalizing the proposal presented by Guha [Phys. Rev. Lett. 106, 240502 (2011)], 10.1103/PhysRevLett.106.240502. It employs code words formed by products of coherent states of fixed mean photon number with multiple phases which, through a passive unitary transformation, reduce to a pulse-position modulation code with multiple pulse phases. The maximum information rate achievable with optimal, yet difficult to implement detection schemes is computed and shown to saturate the classical capacity of the channel in the low-energy regime. An easy to implement receiver based on a conditional Dolinar detection scheme is also proposed, finding that while suboptimal, it allows for improvements in an intermediate photon-number regime with respect to previous proposals.

  8. Receiver functions: An exploration seismic perspective

    NASA Astrophysics Data System (ADS)

    van Manen, Dirk-Jan; Curtis, Andrew; Robertsson, Johan

    2015-04-01

    The receiver function technique is arguably the most successful technique in seismology for crustal and upper mantle characterisation. Prompted by the successful application of the receiver function method to multi-component seabed seismic data to derive shear-wave statics, we explore to what extent the receiver function method can be used for general multi-component reflection seismic data processing and vice-versa. We show that the work in the seismological community on moveout correction and stacking of receiver functions can be extended significantly, building on results from the exploration seismic community. We introduce a novel type of space-time domain receiver function, computed by 2D deconvolution, which treats the spatial aspects of mode-conversion completely analogously to the temporal aspects. Thus, the receiver function becomes a two-dimensional transfer function, which shows how far the P-waves have to be shifted in space and delayed in time to match the corresponding PS-converted waves. In addition, series expansions of the traveltime differences lead naturally to two-term moveout approximations and Dix-Krey-type velocity inversion formulae for both the conventional (i.e., time difference as a function of slowness) as well as novel (i.e., time difference as a function of offset) receiver functions. The two approaches, and the required data pre-processing, are illustrated using synthetic multi-component seismic data. We also introduce a model-independent method for reflection receiver function computation, based on stationary phase analysis, which can be used for deconvolution of anelastic and all other propagation effects. This method is inspired by, and closely related to, interferometry and relies on matching the slowness of a particular PP-reflected wave to the slowness of the corresponding PS-converted wave on the source side, and exploiting the fact that the traveltime difference is stationary for the PP- and PS-wave that is reflected and mode

  9. Performance outlook of the SCRAP receiver

    NASA Astrophysics Data System (ADS)

    Lubkoll, Matti; von Backström, Theodor W.; Harms, Thomas M.

    2016-05-01

    A combined cycle (CC) concentrating solar power (CSP) plant provides significant potential to achieve an efficiency increase and an electricity cost reduction compared to current single-cycle plants. A CC CSP system requires a receiver technology capable of effectively transferring heat from concentrated solar irradiation to a pressurized air stream of a gas turbine. The small number of pressurized air receivers demonstrated to date have practical limitations, when operating at high temperatures and pressures. As yet, a robust, scalable and efficient system has to be developed and commercialized. A novel receiver system, the Spiky Central Receiver Air Pre-heater (SCRAP) concept has been proposed to comply with these requirements. The SCRAP system is conceived as a solution for an efficient and robust pressurized air receiver that could be implemented in CC CSP concepts or standalone solar Brayton cycles without a bottoming Rankine cycle. The presented work expands on previous publications on the thermal modeling of the receiver system. Based on the analysis of a single heat transfer element (spike), predictions for its thermal performance can be made. To this end the existing thermal model was improved by heat transfer characteristics for the jet impingement region of the spike tip as well as heat transfer models simulating the interaction with ambient. While the jet impingement cooling effect was simulated employing a commercial CFD code, the ambient heat transfer model was based on simplifying assumptions in order to employ empirical and analytical equations. The thermal efficiency of a spike under design conditions (flux 1.0 MW/m2, air outlet temperature just below 800 °C) was calculated at approximately 80 %, where convective heat losses account for 16.2 % of the absorbed radiation and radiative heat losses for a lower 2.9 %. This effect is due to peak surface temperatures occurring at the root of the spikes. It can thus be concluded that the geometric

  10. Module utilization committee

    NASA Technical Reports Server (NTRS)

    Volkmer, K.; Praver, G.

    1984-01-01

    Photovoltaic collector modules were declared surplus to the needs of the U.S. Dept. of Energy. The Module Utilization Committee was formed to make appropriate disposition of the surplus modules on a national basis and to act as a broker for requests for these modules originating outside of the National Photovoltaics Program.

  11. Software Defined GPS Receiver for International Space Station

    NASA Technical Reports Server (NTRS)

    Duncan, Courtney B.; Robison, David E.; Koelewyn, Cynthia Lee

    2011-01-01

    JPL is providing a software defined radio (SDR) that will fly on the International Space Station (ISS) as part of the CoNNeCT project under NASA's SCaN program. The SDR consists of several modules including a Baseband Processor Module (BPM) and a GPS Module (GPSM). The BPM executes applications (waveforms) consisting of software components for the embedded SPARC processor and logic for two Virtex II Field Programmable Gate Arrays (FPGAs) that operate on data received from the GPSM. GPS waveforms on the SDR are enabled by an L-Band antenna, low noise amplifier (LNA), and the GPSM that performs quadrature downconversion at L1, L2, and L5. The GPS waveform for the JPL SDR will acquire and track L1 C/A, L2C, and L5 GPS signals from a CoNNeCT platform on ISS, providing the best GPS-based positioning of ISS achieved to date, the first use of multiple frequency GPS on ISS, and potentially the first L5 signal tracking from space. The system will also enable various radiometric investigations on ISS such as local multipath or ISS dynamic behavior characterization. In following the software-defined model, this work will create a highly portable GPS software and firmware package that can be adapted to another platform with the necessary processor and FPGA capability. This paper also describes ISS applications for the JPL CoNNeCT SDR GPS waveform, possibilities for future global navigation satellite system (GNSS) tracking development, and the applicability of the waveform components to other space navigation applications.

  12. Liquid cooled, linear focus solar cell receiver

    DOEpatents

    Kirpich, A.S.

    1983-12-08

    Separate structures for electrical insulation and thermal conduction are established within a liquid cooled, linear focus solar cell receiver for use with parabolic or Fresnel optical concentrators. The receiver includes a V-shaped aluminum extrusion having a pair of outer faces each formed with a channel receiving a string of solar cells in thermal contact with the extrusion. Each cell string is attached to a continuous glass cover secured within the channel with spring clips to isolate the string from the external environment. Repair or replacement of solar cells is effected simply by detaching the spring clips to remove the cover/cell assembly without interrupting circulation of coolant fluid through the receiver. The lower surface of the channel in thermal contact with the cells of the string is anodized to establish a suitable standoff voltage capability between the cells and the extrusion. Primary electrical insulation is provided by a dielectric tape disposed between the coolant tube and extrusion. Adjacent solar cells are soldered to interconnect members designed to accommodate thermal expansion and mismatches. The coolant tube is clamped into the extrusion channel with a releasably attachable clamping strip to facilitate easy removal of the receiver from the coolant circuit.

  13. Dish/stirling hybrid-receiver

    DOEpatents

    Mehos, Mark S.; Anselmo, Kenneth M.; Moreno, James B.; Andraka, Charles E.; Rawlinson, K. Scott; Corey, John; Bohn, Mark S.

    2002-01-01

    A hybrid high-temperature solar receiver is provided which comprises a solar heat-pipe-receiver including a front dome having a solar absorber surface for receiving concentrated solar energy, a heat pipe wick, a rear dome, a sidewall joining the front and the rear dome, and a vapor and a return liquid tube connecting to an engine, and a fossil fuel fired combustion system in radial integration with the sidewall for simultaneous operation with the solar heat pipe receiver, the combustion system comprising an air and fuel pre-mixer, an outer cooling jacket for tangentially introducing and cooling the mixture, a recuperator for preheating the mixture, a burner plenum having an inner and an outer wall, a porous cylindrical metal matrix burner firing radially inward facing a sodium vapor sink, the mixture ignited downstream of the matrix forming combustion products, an exhaust plenum, a fossil-fuel heat-input surface having an outer surface covered with a pin-fin array, the combustion products flowing through the array to give up additional heat to the receiver, and an inner surface covered with an extension of the heat-pipe wick, a pin-fin shroud sealed to the burner and exhaust plenums, an end seal, a flue-gas diversion tube and a flue-gas valve for use at off-design conditions to limit the temperature of the pre-heated air and fuel mixture, preventing pre-ignition.

  14. Direct broadcast satellite-radio, receiver development

    NASA Technical Reports Server (NTRS)

    Vaisnys, A.; Bell, D.; Gevargiz, J.; Golshan, Nasser

    1993-01-01

    The status of the ongoing Direct Broadcast Satellite-Radio (DBS-R) Receiver Development Task being performed at the Jet Propulsion Laboratory, California Institute of Technology (JPL) is reported. This work is sponsored by the Voice of America/U.S. Information Agency through an agreement with NASA. The objective of this task is to develop, build, test, and demonstrate a prototype receiver that is compatible with reception of digital audio programs broadcast via satellites. The receiver is being designed to operate under a range of reception conditions, including fixed, portable, and mobile, as well as over a sufficiently wide range of bit rates to accommodate broadcasting systems with different cost/audio quality objectives. While the requirements on the receiver are complex, the eventual goal of the design effort is to make the design compatible with low cost production as a consumer product. One solution may be a basic low cost core design suitable for a majority of reception conditions, with optional enhancements for reception in especially difficult environments. Some of the receiver design parameters were established through analysis, laboratory tests, and a prototype satellite experiment accomplished in late 1991. Many of the necessary design trades will be made during the current simulation effort, while a few of the key design options will be incorporated into the prototype for evaluation during the planned satellite field trials.

  15. Schottky Heterodyne Receivers With Full Waveguide Bandwidth

    NASA Technical Reports Server (NTRS)

    Hesler, Jeffrey; Crowe, Thomas

    2011-01-01

    Compact THz receivers with broad bandwidth and low noise have been developed for the frequency range from 100 GHz to 1 THz. These receivers meet the requirements for high-resolution spectroscopic studies of planetary atmospheres (including the Earth s) from spacecraft, as well as airborne and balloon platforms. The ongoing research is significant not only for the development of Schottky mixers, but also for the creation of a receiver system, including the LO chain. The new receivers meet the goals of high sensitivity, compact size, low total power requirement, and operation across complete waveguide bands. The exceptional performance makes these receivers ideal for the broader range of scientific and commercial applications. These include the extension of sophisticated test and measurement equipment to 1 THz and the development of low-cost imaging systems for security applications and industrial process monitoring. As a particular example, a WR-1.9SHM (400-600 GHz) has been developed (see Figure 1), with state-of-the-art noise temperature ranging from 1,000-1,800 K (DSB) over the full waveguide band. Also, a Vector Network Analyzer extender has been developed (see Figure 2) for the WR1.5 waveguide band (500 750 GHz) with 100-dB dynamic range.

  16. Liquid cooled, linear focus solar cell receiver

    DOEpatents

    Kirpich, Aaron S.

    1985-01-01

    Separate structures for electrical insulation and thermal conduction are established within a liquid cooled, linear focus solar cell receiver for use with parabolic or Fresnel optical concentrators. The receiver includes a V-shaped aluminum extrusion having a pair of outer faces each formed with a channel receiving a string of solar cells in thermal contact with the extrusion. Each cell string is attached to a continuous glass cover secured within the channel with spring clips to isolate the string from the external environment. Repair or replacement of solar cells is effected simply by detaching the spring clips to remove the cover/cell assembly without interrupting circulation of coolant fluid through the receiver. The lower surface of the channel in thermal contact with the cells of the string is anodized to establish a suitable standoff voltage capability between the cells and the extrusion. Primary electrical insulation is provided by a dielectric tape disposed between the coolant tube and extrusion. Adjacent solar cells are soldered to interconnect members designed to accommodate thermal expansion and mismatches. The coolant tube is clamped into the extrusion channel with a releasably attachable clamping strip to facilitate easy removal of the receiver from the coolant circuit.

  17. STRS SpaceWire FPGA Module

    NASA Technical Reports Server (NTRS)

    Lux, James P.; Taylor, Gregory H.; Lang, Minh; Stern, Ryan A.

    2011-01-01

    An FPGA module leverages the previous work from Goddard Space Flight Center (GSFC) relating to NASA s Space Telecommunications Radio System (STRS) project. The STRS SpaceWire FPGA Module is written in the Verilog Register Transfer Level (RTL) language, and it encapsulates an unmodified GSFC core (which is written in VHDL). The module has the necessary inputs/outputs (I/Os) and parameters to integrate seamlessly with the SPARC I/O FPGA Interface module (also developed for the STRS operating environment, OE). Software running on the SPARC processor can access the configuration and status registers within the SpaceWire module. This allows software to control and monitor the SpaceWire functions, but it is also used to give software direct access to what is transmitted and received through the link. SpaceWire data characters can be sent/received through the software interface, as well as through the dedicated interface on the GSFC core. Similarly, SpaceWire time codes can be sent/received through the software interface or through a dedicated interface on the core. This innovation is designed for plug-and-play integration in the STRS OE. The SpaceWire module simplifies the interfaces to the GSFC core, and synchronizes all I/O to a single clock. An interrupt output (with optional masking) identifies time-sensitive events within the module. Test modes were added to allow internal loopback of the SpaceWire link and internal loopback of the client-side data interface.

  18. Almond brush module cutter

    SciTech Connect

    Zohns, M.A.; Jenkins, B.M.; Mehlschau, J.J.; Morrison, D.

    1983-06-01

    This paper addresses the design, construction, and evaluation of an almond brush module cutter. The module cutter is one link in a system which processes tree prunings for fuel and fiber. This system includes a modified cotton module builder, a module mover, the cutter, and a tub grinder. An economic analysis of the cutter is presented along with the problems involved in cutting brush modules.

  19. Ultra-Low-Noise W-Band MMIC Detector Modules

    NASA Technical Reports Server (NTRS)

    Gaier, Todd C.; Samoska, Lorene A.; Kangaslahti, Pekka P.; Van Vinkle, Dan; Tantawi, Sami; Fox, John; Church, Sarah E.; Lau, Jusy M.; Sieth, Matthew M.; Voll, Patricia E.; Bryerton, Eric

    2010-01-01

    A monolithic microwave integrated circuit (MMIC) receiver can be used as a building block for next-generation radio astronomy instruments that are scalable to hundreds or thousands of pixels. W-band (75-110 GHz) low-noise receivers are needed for radio astronomy interferometers and spectrometers, and can be used in missile radar and security imagers. These receivers need to be designed to be mass-producible to increase the sensitivity of the instrument. This innovation is a prototyped single-sideband MMIC receiver that has all the receiver front-end functionality in one small and planar module. The planar module is easy to assemble in volume and does not require tuning of individual receivers. This makes this design low-cost in large volumes.

  20. Olympus receiver evaluation and phase noise measurements

    NASA Technical Reports Server (NTRS)

    Campbell, Richard L.; Wang, Huailiang; Sweeney, Dennis

    1990-01-01

    A set of measurements performed by the Michigan Tech Sensing and Signal Processing Group on the analog receiver built by the Virginia Polytechnic Institute (VPI) and the Jet Propulsion Laboratory (JPL) for propagation measurements using the Olympus Satellite is described. Measurements of local oscillator (LO) phase noise were performed for all of the LOs supplied by JPL. In order to obtain the most useful set of measurements, LO phase noise measurements were made using the complete VPI receiver front end. This set of measurements demonstrates the performance of the receiver from the Radio Frequency (RF) input through the high Intermediate Frequency (IF) output. Three different measurements were made: LO phase noise with DC on the voltage controlled crystal oscillator (VCXO) port; LO phase noise with the 11.381 GHz LO locked to the reference signal generator; and a reference measurement with the JPL LOs out of the system.

  1. Air Brayton Solar Receiver, phase 2

    NASA Technical Reports Server (NTRS)

    Deanda, L. E.

    1981-01-01

    An air Brayton solar receiver (ABSR) is discussed. The ABSR consists of a cylindrical, insulated, offset plate fin heat exchanger which is mounted at the focal plane of a fully tracking parabolic solar collector. The receiver transfer heat from the concentrated solar radiation (which impinges on the inside walls of the heat exchanger) to the working fluid i.e., air. The hot air would then e used to drive a small Brayton cycle heat engine. The engine in turn drives a generator which produces electrical energy. Symmetrical and asymmetrical solar power input into the ABSR are analyzed. The symmetrical cases involve the baseline incident flux and the axially shifted incident fluxes. The asymmetrical cases correspond to the solar fluxes that are obtained by reduced solar input from one half of the concentrator or by receiver offset of plus or minus 1 inch from the concentrator optical axis.

  2. Water intoxication in epileptic patients receiving carbamazepine.

    PubMed Central

    Perucca, E; Garratt, A; Hebdige, S; Richens, A

    1978-01-01

    Plasma sodium and osmolality were determined in 80 adult epileptic patients receiving chronic treatment with carbamazepine and in 50 control patients treated with other anticonvulsant drugs. Mean plasma osmolality was significantly lower in the carbamazepine-treated patients but mean plasma sodium did not differ in the two groups. Hyponatraemia was found in five of the carbamazine-treated patients and hypo-osmolality in six. None of the control patients had hyponatraemia and only one had a borderline low osmolality. Three of the 13 patients receiving carbamazepine alone were hyponatraemic. Plasma sodium concentration correlated negatively with both daily carbamazepine dose and serum carbamazepine level. Free water clearance after an oral water load was determined in six patients on carbamazepine alone and in six normal subjects not receiving drug therapy. The capacity of some of the patients to excrete the water load was found to be grossly impaired. PMID:681958

  3. Qualification of TAOS satellite GPS receiver

    NASA Astrophysics Data System (ADS)

    Weninger, Roger M.; Sfeir, Richard; Forgette, Tom T.; Kelton, Phil T.; Najarian, Richard J.

    1992-03-01

    A light-weight, compact GPS receiver developed for a Technology for Autonomous Operational Survivability (TAOS) satellite planned for launch in 1993 is described. The receiver is capable of continuously tracking four primary GPS satellites and sequentially acquiring and tracking other visible satellites with its six channels. Using an eight-state extended Kalman filter it performs pseudo-range and continuous-carrier, delta-range measurements and estimates time-tagged, 3D user position and velocity. Results of qualification testing obtained from a multichannel GPS spaceborne simulation and evaluation system show that with a GPS constellation of 18 satellites and over a period where GDOP is less than 6, the receiver's rms spherical position and per axis velocity errors are less than 14.5 meters and 0.05 m/sec, respectively.

  4. High-temperature solar central receivers

    NASA Astrophysics Data System (ADS)

    Skinrood, A. C.

    1981-07-01

    Designs and concepts for solar central receiver thermal power plants are reviewed. Concentrations of over 1,000 suns are now possible, and seven prototype plants, producing from 1-10 MWe, are close to completion, employing cavity and external receiver configurations. Heat transfer fluids are discussed, noting that the water/steam cycle is emerging as the dominant mode; liquid sodium is benefitting from extensive testing for nuclear power plants; molten salt provides thermal storage at $10-30/kWt-hr; high temperature gas systems (815 C) can be applied for gypsum board drying and NH3 production. Heliostats are all of a steel/glass configuration and require mass production to become economical. Thermal storage systems, applications for repowering in conjunction with conventional power plants, and cogeneration for electricity/process heat are examined, and power costs are projected to match those of coal if the central receiver construction costs can be halved.

  5. Future trends in millimeter-wave receiver design

    NASA Astrophysics Data System (ADS)

    Cardiasmenos, A. G.

    1981-06-01

    The development of short wave receivers with low noise and narrow bandwidths in the millimeter range and directions being followed for mass production for military use are presented. It is noted that surface-oriented GaAs diodes with less than .018 pFd capacitance and series resistance of 3-4 ohms are now available for receiver subassemblies. Schottky diodes are suitable for 20-300 GHz, with optimization so far centering around 94 GHz, and fabrication by thermocompression allows mass production, eliminates whisker induced mechanical failure, and permits high reliability piece-to-piece. Continuing antenna design is noted, as are 15 transmission line media currently known, with fused silica offering the most substantial production history. Broader bandwidths and low cost approaches based on microstrip lines are argued with tradeoffs between noise, cost, and performance. FET IF amplifiers are projected to become practical in the 40-140 GHz region and production parameters for MIC circuits, local oscillator source inclusion, MIC modules, and monolithic GaAs mixer circuits are discussed for electronic warfare, radar warning, and communications applications.

  6. Generalised receiver functions and seismic interferometry

    NASA Astrophysics Data System (ADS)

    Galetti, Erica; Curtis, Andrew

    2012-04-01

    Classical seismological receiver functions are correlational or deconvolutional combinations of vertical and horizontal component seismometer recordings of earthquake waves that focus information on near-receiver subsurface Earth structure and properties. We show that seismic interferometry can be thought of as a generalisation of receiver functions analysis to cases where recordings at pairs of receivers are considered simultaneously, and where either the same or different component recordings are combined. Further, seismic interferometry uses any of deconvolution, convolution and cross-correlation, and energy from either impulsive or random noise sources. We show both how receiver functions can logically be extended to a new, convolutional form, and that the now little-used correlational form of receiver functions contains more intuitive information than previously realised. Seismic interferometry has provided other extraordinary extensions to seismologists' arsenal. Passive noise recordings can be converted into seismograms from virtual (imagined) earthquakes that in turn can be used to image the real Earth. Active sources (e.g., earthquakes or man-made sources) can be redatumed into new, virtual sources elsewhere, or can be converted into virtual sensors (seismometers) that record seismograms from other real earthquakes, man-made sources or noise sources that occur either in the future or in the past. And the ability to construct virtual sources and sensors at desired times and locations (rather than having to wait for earthquake sources that occur at uncontrollable locations) promises more repeatable monitoring of changes in Earth subsurface properties over time. Indeed, so-called coda wave interferometry offers unprecedented accuracy in detecting such changes. Finally, existing theoretical extensions to other regimes such as electromagnetic, electrokinetic and diffusive energy propagation may lead to future revolutions in other domains of science.

  7. Mini-L Loran-C receiver

    NASA Technical Reports Server (NTRS)

    Burhans, R. W.

    1977-01-01

    A brief description of the Loran-C system is presented with a suggested receiver based on a standard AM-FM integrated circuit chip. Construction details of the Mini-L Loran-C prototype front-end are considered. The Mini-L system was bench tested for approximately 500 hours under a variety of reception conditions. The Mini-L concept combined with a microprocessor system is a promising approach to the development of truly low-cost Loran-C receivers for the marine and airborne user.

  8. Building and Testing a Portable VLF Receiver

    NASA Technical Reports Server (NTRS)

    McLaughlin, Robert; Krause, L.

    2014-01-01

    Unwanted emissions or signal noise is a major problem for VLF radio receivers. These can occur from man made sources such as power line hum, which can be prevalent for many harmonics after the fundamental 50 or 60 Hz AC source or from VLF radio transmissions such as LORAN, used for navigation and communications. Natural emissions can also be detrimental to the quality of recordings as some of the more interesting natural emissions such as whistlers or auroral chorus may be drowned out by the more common sferic emissions. VLF receivers must selectively filter out unwanted emissions and amplify the filtered signal to a record-able level without degrading the quality.

  9. A functional description of the advanced receiver

    NASA Technical Reports Server (NTRS)

    Hinedi, S.

    1990-01-01

    The breadboard Advanced Receiver 2 (ARX 2) that is currently being built for future use in NASA's Deep Space Network (DSN) is described. The hybrid analog/digital receiver performs multiple functions including carrier, subcarrier, and symbol synchronization. Tracking can be achieved for residual, suppressed, or hybrid carriers and for both sinusoidal and square-wave subcarriers. Other functions such as time-tagged Doppler extraction and monitor/control are also discussed, including acquisition algorithms and lock-detection schemes. System requirements are specified and a functional description of the ARX 2 is presented. The various digital signal-processing algorithms used are also discussed and illustrated with block diagrams.

  10. Turbulent flow inside a solar concentrator receiver

    NASA Astrophysics Data System (ADS)

    Ramirez, Manuel; Ramos, Eduardo

    2014-11-01

    A solar concentrator receiver is a heat exchanger designed to absorb a beam of radiant heat coming from a field of heliostats. Inside the device, a slow forced flow generated bye an external pressure gradient is present, together with a natural convective a turbulent flow produced by the large temperature gradients due to intense heating. We present a model of this device based on the numerical solution of the mass, momentum and energy conservation equations. We consider heating conditions that lead to turbulence convective flow. For this season, a large eddy simulation model is incorporated. The results are potentially useful for the design of solar concentrator receivers.

  11. Optical Receiver Based On Luminescent Light Trapping

    NASA Technical Reports Server (NTRS)

    Perry, Joseph W.; Cole, Terry; Zewail, Ahmed H.

    1991-01-01

    Experiment demonstrates feasibility of optical-communication receiver based on luminescent light trapping. Light-gathering element plate of transparent material impregnated with laser dye. Light from distant laser transmitter falls on plate and absorbed by dye molecules, which become excited and reradiate. Reradiated light confined within plate by total internal reflection as it propagates toward edge of plate. Light arriving at edge escapes from plate and detected by small, high-speed, high-gain photomultiplier tubes or other photosensitive devices. Simple, inexpensive, and accepts light from almost any angle. Receiver of this configuration supports reception of data at rate of 13 MHz and higher.

  12. Billing and accounts receivable: fundamentals for improvement.

    PubMed

    Bizon, M M

    1993-07-01

    If a healthcare facility's accounts receivable operation is experiencing problems, the patient accounts manager should survey all areas of his or her responsibility to determine the best method of resolving the difficulties. One effective technique to reduce billing problems is to take a proactive--not reactive--approach. If mistakes can be corrected before they get out of control, and if the patient accounts manager can ensure that claims will not be denied, a healthcare facility's accounts receivable should remain in good condition.

  13. The new indicators of accounts receivable excellence.

    PubMed

    Lampi, G L

    1996-01-01

    Calculation of AR days will continue to be a valuable internal measurement tool of accounts receivable excellence. As healthcare organizations move toward managed care through a mix of reimbursement systems--many with conflicting incentives--the director of patient accounting must approach each system separately and ensure that the hospital receives all of the reimbursement to which it is entitled. The director of patient accounting must understand the industry and recognize that healthcare reimbursement will almost certainly continue to become more complex rather than simpler. Creativity will be a necessity, and good luck will be an advantage.

  14. Histaminergic Mechanisms for Modulation of Memory Systems

    PubMed Central

    Köhler, Cristiano André; da Silva, Weber Cláudio; Benetti, Fernando; Bonini, Juliana Sartori

    2011-01-01

    Encoding for several memory types requires neural changes and the activity of distinct regions across the brain. These areas receive broad projections originating in nuclei located in the brainstem which are capable of modulating the activity of a particular area. The histaminergic system is one of the major modulatory systems, and it regulates basic homeostatic and higher functions including arousal, circadian, and feeding rhythms, and cognition. There is now evidence that histamine can modulate learning in different types of behavioral tasks, but the exact course of modulation and its mechanisms are controversial. In the present paper we review the involvement of the histaminergic system and the effects histaminergic receptor agonists/antagonists have on the performance of tasks associated with the main memory types as well as evidence provided by studies with knockout models. Thus, we aim to summarize the possible effects histamine has on modulation of circuits involved in memory formation. PMID:21876818

  15. System and Method for Generating a Frequency Modulated Linear Laser Waveform

    NASA Technical Reports Server (NTRS)

    Pierrottet, Diego F. (Inventor); Petway, Larry B. (Inventor); Amzajerdian, Farzin (Inventor); Barnes, Bruce W. (Inventor); Lockard, George E. (Inventor); Hines, Glenn D. (Inventor)

    2014-01-01

    A system for generating a frequency modulated linear laser waveform includes a single frequency laser generator to produce a laser output signal. An electro-optical modulator modulates the frequency of the laser output signal to define a linear triangular waveform. An optical circulator passes the linear triangular waveform to a band-pass optical filter to filter out harmonic frequencies created in the waveform during modulation of the laser output signal, to define a pure filtered modulated waveform having a very narrow bandwidth. The optical circulator receives the pure filtered modulated laser waveform and transmits the modulated laser waveform to a target.

  16. Photovoltaic solar concentrator module

    SciTech Connect

    Chiang, C.J.

    1991-05-16

    This invention consists of a planar photovoltaic concentrator module for producing an electrical signal from incident solar radiation which includes an electrically insulating housing having a front wall, an opposing back wall and a hollow interior. A solar cell having electrical terminals is positioned within the interior of the housing. A planar conductor is connected with a terminal of the solar cell of the same polarity. A lens forming the front wall of the housing is operable to direct solar radiation incident to the lens into the interior of the housing. A refractive optical element in contact with the solar cell and facing the lens receives the solar radiation directed into the interior of the housing by the lens and directs the solar radiation to the solar cell to cause the solar cell to generate an electrical signal. An electrically conductive planar member is positioned in the housing to rest on the housing back wall in supporting relation with the solar cell terminal of opposite polarity. The planar member is operable to dissipate heat radiated by the solar cell as the solar cell generates an electrical signal and further forms a solar cell conductor connected with the solar cell terminal to permit the electrical signal generated by the solar cell to be measured between the planar member and the conductor.

  17. Power meter ratio method of stabilizing a resonant modulator

    DOEpatents

    Lentine, Anthony L.; Cox, Jonathan Albert

    2016-10-11

    Methods and systems for stabilizing a resonant modulator include receiving pre-modulation and post-modulation portions of a carrier signal, determining the average power from these portions, comparing an average input power to the average output power, and operating a heater coupled to the modulator based on the comparison. One system includes a pair of input structures, one or more processing elements, a comparator, and a control element. The input structures are configured to extract pre-modulation and post-modulation portions of a carrier signal. The processing elements are configured to determine average powers from the extracted portions. The comparator is configured to compare the average input power and the average output power. The control element operates a heater coupled to the modulator based on the comparison.

  18. GMSK Modulation for Deep Space Applications

    NASA Technical Reports Server (NTRS)

    Shambayati, Shervin; Lee, Dennis K.

    2012-01-01

    Due to scarcity of spectrum at 8.42 GHz deep space Xband allocation, many deep space missions are now considering the use of higher order modulation schemes instead of the traditional binary phase shift keying (BPSK). One such scheme is pre-coded Gaussian minimum shift keying (GMSK). GMSK is an excellent candidate for deep space missions. GMSK is a constant envelope, bandwidth efficien modulation whose frame error rate (FER) performance with perfect carrier tracking and proper receiver structure is nearly identical to that of BPSK. There are several issues that need to be addressed with GMSK however. Specificall, we are interested in the combined effects of spectrum limitations and receiver structure on the coded performance of the X-band link using GMSK. The receivers that are typically used for GMSK demodulations are variations on offset quadrature phase shift keying (OQPSK) receivers. In this paper we consider three receivers: the standard DSN OQPSK receiver, DSN OQPSK receiver with filte ed input, and an optimum OQPSK receiver with filte ed input. For the DSN OQPSK receiver we show experimental results with (8920, 1/2), (8920, 1/3) and (8920, 1/6) turbo codes in terms of their error rate performance. We also consider the tracking performance of this receiver as a function of data rate, channel code and the carrier loop signal-to-noise ratio (SNR). For the other two receivers we derive theoretical results that will show that for a given loop bandwidth, a receiver structure, and a channel code, there is a lower data rate limit on the GMSK below which a higher SNR than what is required to achieve the required FER on the link is needed. These limits stem from the minimum loop signal-to-noise ratio requirements on the receivers for achieving lock. As a result of this, for a given channel code and a given FER, there could be a gap between the maximum data rate that BPSK can support without violating the spectrum limits and the minimum data rate that GMSK can support

  19. 47 CFR 80.913 - Radiotelephone receivers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... radiotelephone installation must have a sensitivity of at least 50 microvolts in the case of MF equipment, and 1... be capable of efficient operation when energized by the reserve source of energy. (g) The sensitivity... sensitivity of a required receiver computed on this basis must be furnished upon request of the Commission....

  20. Solar-central-receiver fuels and chemicals

    NASA Astrophysics Data System (ADS)

    Carling, R. W.; Fish, J. D.; Radosevich, L. G.; Vitko, J., Jr.

    1981-08-01

    Solar central receiver fuels and chemicals processes were studied. Ethane pyrolysis and steam reforming of methane were investigated in-depth in addition to coal gasification, oil shale retorting, and biomass flash pyrolysis. The study criteria, status of ongoing work, and future activities are described.

  1. A 20 GHz Active Receive Slot Array

    NASA Technical Reports Server (NTRS)

    Tulintseff, A. N.; Lee, K.; Sukamto, L.; Chew, W.

    1994-01-01

    A 20 GHz active receive slot array has been developed for operation in the downlink frequency band of NASA's Advanced Communication Technology Satellite (ACTS) for the ACTS Mobile Terminal (AMT) project. The AMT is to demonstrate voice and data communication between a mobile terminal in Los Angeles, California, and a fixed terminal in Cleveland, Ohio, via the ACTS satellite.

  2. PiVoT GPS Receiver

    NASA Technical Reports Server (NTRS)

    Wennersten, Miriam Dvorak; Banes, Anthony Vince; Boegner, Gregory J.; Dougherty, Lamar; Edwards, Bernard L.; Roman, Joseph; Bauer, Frank H. (Technical Monitor)

    2001-01-01

    NASA Goddard Space Flight Center has built an open architecture, 24 channel space flight GPS receiver. The CompactPCI PiVoT GPS receiver card is based on the Mitel/GEC Plessey Builder-2 board. PiVoT uses two Plessey 2021 correlators to allow tracking of up to 24 separate GPS SV's on unique channels. Its four front ends can support four independent antennas, making it a useful card for hosting GPS attitude determination algorithms. It has been built using space quality, radiation tolerant parts. The PiVoT card will track a weaker signal than the original Builder 2 board. It also hosts an improved clock oscillator. The PiVoT software is based on the original Plessey Builder 2 software ported to the Linux operating system. The software is POSIX complaint and can easily be converted to other POSIX operating systems. The software is open source to anyone with a licensing agreement with Plessey. Additional tasks can be added to the software to support GPS science experiments or attitude determination algorithms. The next generation PiVoT receiver will be a single radiation hardened CompactPCI card containing the microprocessor and the GPS receiver optimized for use above the GPS constellation. PiVoT was flown successfully on a balloon in July, 2001, for its first non-simulated flight.

  3. 47 CFR 32.1170 - Receivables.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., matured rents, and interest receivable under monthly settlements on short-term loans, advances, and open... shall be included in Account 1410, Other noncurrent assets, as a reduction of the carrying value of the..., Other noncurrent assets. (h) Subsidiary record categories shall be maintained in order that the...

  4. 47 CFR 32.1170 - Receivables.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., matured rents, and interest receivable under monthly settlements on short-term loans, advances, and open... shall be included in Account 1410, Other noncurrent assets, as a reduction of the carrying value of the..., Other noncurrent assets. (h) Subsidiary record categories shall be maintained in order that the...

  5. Kopp Receives 2012 William Gilbert Award: Citation

    NASA Astrophysics Data System (ADS)

    Kirschvink, Joseph L.

    2013-10-01

    Robert E. Kopp received the 2012 William Gilbert Award at the 2012 AGU Fall Meeting, held 3-7 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  6. 7 CFR 29.42 - Receiving station.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Regulations Definitions § 29.42 Receiving station. Points at which producer tobacco is offered for marketing (other than sale at auction on a designated market), including tobacco auction warehouses,...

  7. Some Books about Alaska Received in 1990.

    ERIC Educational Resources Information Center

    Alaska State Dept. of Education, Juneau. Div. of State Libraries.

    This annual bibliography of Alaska- and Arctic-related publications received by the Alaska Division of State Libraries is divided into three categories. There are 26 titles in the "Juvenile Fiction" section, 122 in the "Adult Non-Fiction" section, and 19 in the "Adult Fiction" section. Government publications are…

  8. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... extends beyond the plane surfaces of the enclosure. (2) Maximum test voltage means 130 root mean square volts if the receiver is designed to operate from nominal 110 to 120 root mean square volt power sources... nominal 110 to 120 root mean square volts, maximum test voltage means 110 percent of the nominal root...

  9. Fung receives 2004 Roger Revelle Medal

    NASA Astrophysics Data System (ADS)

    Holland, Elisabeth A.; Doney, Scott A.; Fung, Inez

    Inez Fung received the Revelle Medal at the 2004 Fall Meeting Honors Ceremony on 15 December, in San Francisco, California. The medal is given for outstanding contributions in atmospheric sciences, atmosphere-ocean coupling, atmosphere-land coupling, biogeochemical cycles, climate, or related aspects of the Earth system.

  10. Using Unmanned Aerial Vehicles and GPS Receivers

    NASA Technical Reports Server (NTRS)

    Gary, B.

    1995-01-01

    It is proposed that a small fleet of unmanned aerial vehicles (UAVs) be used over a period of years to monitor the rise of pressure surfaces caused by the hypothesized rise in average temperature of the troposphere due to global warming. Global Positioning Satellite System (GPS) receivers would be used for the precise tracking required.

  11. Reasons Parents Exempt Children from Receiving Immunizations

    ERIC Educational Resources Information Center

    Luthy, Karlen E.; Beckstrand, Renea L.; Callister, Lynn C.; Cahoon, Spencer

    2012-01-01

    School nurses are on the front lines of educational efforts to promote childhood vaccinations. However, some parents still choose to exempt their children from receiving vaccinations for personal reasons. Studying the beliefs of parents who exempt vaccinations allows health care workers, including school nurses, to better understand parental…

  12. 7 CFR 29.42 - Receiving station.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Receiving station. 29.42 Section 29.42 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS...

  13. Why Receiving Feedback Collides with Self Determination

    ERIC Educational Resources Information Center

    ten Cate, Olle Th. J.

    2013-01-01

    Providing feedback to trainees in clinical settings is considered important for development and acquisition of skill. Despite recommendations how to provide feedback that have appeared in the literature, research shows that its effectiveness is often disappointing. To understand why receiving feedback is more difficult than it appears, this paper…

  14. Workshop summary: Receivers for laser power beaming

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    1993-01-01

    At the Space Photovoltaics Research and Technology (SPRAT) conference at NASA Lewis Research Center, a workshop session was held to discuss issues involved in using photovoltaic arrays ('solar cells') to convert laser power into electrical power for use as receiving elements for beamed power.

  15. Signal Reception via Multi-Platform Receivers

    DTIC Science & Technology

    2012-09-01

    interference cancellation, multi-platform receivers, signal collection, signal interception 15. NUMBER OF PAGES 71 16. PRICE CODE 17. SECURITY ...CLASSIFICATION OF REPORT Unclassified 18. SECURITY CLASSIFICATION OF THIS PAGE Unclassified 19. SECURITY CLASSIFICATION OF ABSTRACT Unclassified...Quadrature Phase Shift Keying SIC Successive Interference Cancellation SNR Signal-To-Noise Ratio SOI Signal Of Interest WLAN Wireless Local Area

  16. Hybrid receiver conceptual design and test report

    NASA Technical Reports Server (NTRS)

    Klare, S. W.; Crawford, J. J.

    1978-01-01

    The Hybrid Receiver described uses an acquisition and demodulation scheme tailored to the Jovian environment. The large Doppler offsets expected during initial acquisition led to development of the Hilbert Acquisition Aid, which provides for rapid acquisition for low signal to noise densities.

  17. Bit Error Rate Performance of Partially Coherent Dual-Branch SSC Receiver over Composite Fading Channels

    NASA Astrophysics Data System (ADS)

    Milić, Dejan N.; Đorđević, Goran T.

    2013-01-01

    In this paper, we study the effects of imperfect reference signal recovery on the bit error rate (BER) performance of dual-branch switch and stay combining receiver over Nakagami-m fading/gamma shadowing channels with arbitrary parameters. The average BER of quaternary phase shift keying is evaluated under the assumption that the reference carrier signal is extracted from the received modulated signal. We compute numerical results illustrating simultaneous influence of average signal-to-noise ratio per bit, fading severity, shadowing, phase-locked loop bandwidth-bit duration (BLTb) product, and switching threshold on BER performance. The effects of BLTb on receiver performance under different channel conditions are emphasized. Optimal switching threshold is determined which minimizes BER performance under given channel and receiver parameters.

  18. Conditional pulse nulling receiver for multi-pulse PPM and binary quantum coding signals

    NASA Astrophysics Data System (ADS)

    Zuo, Yuan; Chen, Tian; Zhu, Bing

    2016-10-01

    Conditional pulse nulling (CPN) receiver is proposed by Dolinar to discriminate pulse position modulation (PPM) signals. The receiver, which uses a beam splitter and an on-off photon detector can outperform the standard quantum limit (SQL) for PPM signals. In this paper, this receiver is applied to multi-pulse PPM (MPPM) and binary quantum coding signals, and a dynamic programming algorithm is proposed to optimize the control strategy. The MPPM signals are used to improve the band-utilization efficiency, and the binary quantum coding enables the communication system to correct the error. Numerical simulation results show that the CPN receiver with optimized strategy outperform SQL for both MPPM and binary quantum coding signals.

  19. Iterative Receiver in Time-Frequency Domain for Shallow Water Acoustic Channel

    NASA Astrophysics Data System (ADS)

    Zhao, Liang; Ge, Jianhua

    2012-03-01

    Inter-symbol interference (ISI) caused by multi-path propagation, especially in shallow water channel, degrades the performance of underwater acoustic (UWA) communication systems. In this paper, we combine soft minimum mean squared error (MMSE) equalization and the serially concatenated trellis coded modulation (SCTCM) decoding to develop an iterative receiver in time-frequency domain (TFD) for underwater acoustic point to point communications. Based on sound speed profile (SSP) measured in the lake and finite-element ray (FER) tracing method (Bellhop), the shallow water channel is constructed to evaluate the performance of the proposed iterative receiver. The results suggest that the proposed iterative receiver can reduce the calculation complexity of the equalizer and obtain better performance using less receiving elements.

  20. Performance analysis of MRC spatial diversity receiver system for satellite-to-ground downlink optical transmissions

    NASA Astrophysics Data System (ADS)

    Li, Kangning; Ma, Jing; Tan, Liying; Yu, Siyuan; Cao, Yubin

    2016-10-01

    The performances of satellite-to-ground downlink optical communications over Gamma-Gamma distributed turbulence are studied for multiple apertures receiver system. Maximum ratio combining (MRC) technique is considered as a combining scheme to mitigate the atmospheric turbulence under thermal noise limited conditions. Bit-error rate (BER) performances for on-off keying (OOK) modulated direct detection optical communications are analyzed for MRC diversity receptions through an approximation method. To show the net diversity gain of multiple apertures receiver system, BER performances of MRC receiver system are compared with a single monolithic aperture receiver system with the same total aperture area (same average total incident optical power) for satellite-to-ground downlink optical communications. All the numerical results are also verified by Monte-Carlo (MC) simulations.