The preparation procedure used to obtain superconducting thin films by radio frequency magnetron sputtering of a single mosaic target is described in detail. The single mosaic target is composed of (Y-Er), BaF2, and Cu.
Topics: NASA Technical Reports Server (NTRS), HIGH TEMPERATURE SUPERCONDUCTORS, MAGNETRON SPUTTERING,...
In order to meet the requirements for precision pointing of 34-m antennas, adequate control design and simulation software have to be developed along with a detailed description of the supporting analytical tools. This article describes a control system model for the elevation drive of the DSS 13 antenna. The model allows one to simulate elevation dynamics, cross-coupled dynamics in azimuth and elevation, and RF pointing error. A modal state-space model of the antenna structure was obtained...
Topics: NASA Technical Reports Server (NTRS), ANTENNA DESIGN, CONTROL SIMULATION, CONTROL SYSTEMS DESIGN,...
Environmental radio frequency (RF) data over a broad band of frequencies (30 MHz to 1000 MHz) were obtained to evaluate the electromagnetic environment in airspace around several airports. An RF signal measurement system was designed utilizing a spectrum analyzer connected to the NASA Lancair Columbia 300 aircraft's VHF/UHF navigation antenna. This paper presents an overview of the RF measurement system and provides analysis of sample RF signal measurement data. This aircraft installation...
Topics: NASA Technical Reports Server (NTRS), FREQUENCY MEASUREMENT, RADIO FREQUENCIES, AIRBORNE EQUIPMENT,...
Antimatter represents the pinnacle of energy density, offering the potential to enhance current fusion/fission concepts enabling various classes of deep space missions. Current production rates are sufficient to support proof-of-concept evaluation of many key technologies associated with antimatter-derived propulsion. Storage has been identified as a key enabling technology for all antimatter-related operations, and as such is the current focus of this NASA-MSFC effort to design and fabricate a...
Topics: NASA Technical Reports Server (NTRS), POSITIVE IONS, MATTER-ANTIMATTER PROPULSION, IONS,...
228
228
Jul 26, 2010
07/10
by
Coe, Paul L., Jr.; Turner, Steven G.; Owens, D. Bruc
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An investigation was conducted to determine the low-speed flight dynamic behavior of a representative advanced turboprop business/commuter aircraft concept. Free-flight tests were conducted in the NASA Langley Research Center's 30- by 60-Foot Tunnel. In support of the free-flight tests, conventional static, dynamic, and free-to-roll oscillation tests were performed. Tests were intended to explore normal operating and post stall flight conditions, and conditions simulating the loss of power in...
Topics: COMMUNICATION SATELLITES, DIGITAL DATA, RADIO FREQUENCIES, TRANSMITTER RECEIVERS, PULSE...
294
294
May 23, 2011
05/11
by
Lawrence, Charle
texts
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The broad scope of aeropropulsion multidisciplinary applications necessitates that a collection of approaches, with distinct capabilities, be developed. Three general approaches to multidisciplinary simulations have been identified. The three approaches; loosely coupled, coupled process, and multiphysics, provide a comprehensive collection of capabilities for multidisciplinary aeropropulsion analysis. At the data access level, or loosely coupled approach of coupling, existing disciplinary...
Topics: ANTENNA ARRAYS, RADIO FREQUENCIES, MICROELECTRONICS, DIGITAL SYSTEMS, FEEDBACK, ANALOG CIRCUITS,...
Both experimental and theoretical studies are presented on spectrum analysis of nuclear quadrupole resonance of antimony and arsenic tellurides. Numerical solutions for secular equations of the quadrupole interaction energy are also discussed.
Topics: NASA Technical Reports Server (NTRS), NUCLEAR MAGNETIC RESONANCE, QUADRUPOLES, ANTIMONY, ARSENIC,...
The results of the design, development, and test of experimental and production units of PPM focused traveling wave tube that produces 225 watts of CW RF power over 85 MHz centered at 12.080 GHz are presented. The tube uses a coupled cavity RF circuit with a velocity taper for greater than 26 percent basic efficiency. Overall efficiency of 50 percent is achieved by the incorporation of a multistage depressed collector designed at NASA Lewis Research Center. The collector is cooled by direct...
Topics: NASA Technical Reports Server (NTRS), BROADCASTING, COMMUNICATIONS TECHNOLOGY SATELLITE, NASA...
The feasibility of using spread spectrum techniques to provide a low-cost multiple access system for a very large number of low data terminals was investigated. Two applications of spread spectrum technology to very small aperture terminal (VSAT) satellite communication networks are presented. Two spread spectrum multiple access systems which use a form of noncoherent M-ary FSK (MFSK) as the primary modulation are described and the throughput analyzed. The analysis considers such factors as...
Topics: NASA Technical Reports Server (NTRS), CHIRP SIGNALS, MULTIPLE ACCESS, SATELLITE COMMUNICATION,...
In the present air traffic system, information presented to the transport aircraft cockpit crew may originate from a variety of sources and may be presented to the crew in visual or aural form, either through cockpit instrument displays or, most often, through voice communication. Voice radio communications are the most error prone method for air-ground data link. Voice messages can be misstated or misunderstood and radio frequency congestion can delay or obscure important messages. To prevent...
Topics: NASA Technical Reports Server (NTRS), AIR TRAFFIC CONTROL, COCKPITS, DATA LINKS, DATA TRANSMISSION,...
In the Space Exploration Initiative (SEI) mission scenarios, expanding human presence is the primary driver for high data rate Mars-Earth communications. To support an expanding human presence, the data rate requirement will be gradual, following the phased implementation over time of the evolving SEI mission. Similarly, the growth and evolution of the space communications infrastructure to serve this requirement will also be gradual to efficiently exploit the useful life of the installed...
Topics: NASA Technical Reports Server (NTRS), SPACE COMMUNICATION, SPACE EXPLORATION, TECHNOLOGY...
T2L2 (Time Transfer by Laser Link) is a new generation time transfer experiment based on the principles of LASSO (Laser Synchronization from Synchronous Orbit) and used with an operational procedure developed at OCA (Observatoire de la Cote d'Azur) during the active intercontinental phase of LASSO. The hardware improvements could lead to a precision better than 10 ps for time transfer (flying clock monitoring or ground based clock comparison). Such a package could fly on any spacecraft with a...
Topics: NASA Technical Reports Server (NTRS), ATOMIC CLOCKS, EUROPEAN SPACE PROGRAMS, GLOBAL POSITIONING...
Tnis paper will focus on developing an exotic switching technique that enhances the DC-to-RF conversion efficiency of microwave power amplifiers. For years, switching techniques implemented in the 10 kHz to 30 MHz region have resulted in DC-to-RF conversion efficiencies of 90-95-percent. Currently amplifier conversion efficiency, in the 2-3 GHz region approaches, 10-20-percent. Using a combination of analytical modeling and hardware testing, a High Efficiency Microwave Power Amplifier was built...
Topics: NASA Technical Reports Server (NTRS), POWER AMPLIFIERS, MICROWAVES, RADIO FREQUENCIES, ENERGY...
The first mission of the Tethered Satellite deployer was flown onboard Atlantis in 1992 during the Space Transportation System (STS) flight STS-46. Due to a mechanical interference with the level wind mechanism the satellite was only Deployed to 256 m rather than the planned 20,000 m. Other problems were also experienced during the STS-46 flight and several modifications were made to the Deployer and Satellite. STS-75 was a reflight of the Tethered Satellite System 1 (TSS-1) designated as...
Topics: NASA Technical Reports Server (NTRS), SPACE TRANSPORTATION SYSTEM FLIGHTS, TETHERED SATELLITES,...
In this paper, a novel miniature inductor and a pick-up antenna for contact less powering and RF telemetry from implantable bio-MEMS sensors are presented. The design of the inductor and the pick-up antenna are discussed. In addition, the measured characteristics at the design frequency of 330 MHz have been shown.
Topics: NASA Technical Reports Server (NTRS), TELEMETRY, INDUCTORS, REMOTE SENSING, MICROELECTROMECHANICAL...
Outer planetary exploration spacecraft have relied on Radioisotope Power Systems (RPS) to provide power. This is necessary as solar power is not useful beyond the inner planets. For propulsion these spacecraft have made use of chemical systems. A study was undertaken to look at the possibility of designing a spacecraft for outer planetary exploration that would use an RPS in combination with Electric Propulsion. That is, the RPS would be the sole power provider to the EP system. Recent...
Topics: NASA Technical Reports Server (NTRS), ELECTRIC PROPULSION, SPACE EXPLORATION, SPACECRAFT...
Printed multi-turn loop antennas have been designed for contactless powering of, and reception of radio signals transmitted by, surgically implantable biotelemetric sensor units operating at frequencies in the vicinity of 300 MHz.
Topics: NASA Technical Reports Server (NTRS), BIOTELEMETRY, LOOP ANTENNAS, RADIO FREQUENCIES,...
Heat pipe life tests have seldom been conducted on a systematic basis. Typically, one or more heat pipes are built and tested for an extended period at a single temperature with simple condenser loading. Results are often reported describing the wall material, working fluid, test temperature, test duration, and occasionally the nature of any failure. Important information such as design details, processing procedures, material assay, power throughput, and radial power density are usually not...
Topics: NASA Technical Reports Server (NTRS), HEAT PIPES, RADIO FREQUENCIES, REFRACTORY METALS, WORKING...
In a proposed digital signal-processing technique, a radio receiver would control the phasing of a phased-array antenna to aim the peaks of the antenna radiation pattern toward desired signal sources while aiming the nulls of the pattern toward interfering signal sources. The technique was conceived for use in a Global Positioning System (GPS) receiver, for which the desired signal sources would be GPS satellites and typical interference sources would be terrestrial objects that cause multipath...
Topics: NASA Technical Reports Server (NTRS), ANTENNA ARRAYS, ANTENNA RADIATION PATTERNS, DOWN-CONVERTERS,...
A new composite material of singlewalled carbon nanotubes (SWNTs) displays radio frequency (0 to 1 GHz) permittivity properties that can be adjusted based upon the nanotube composition. When varying ratios of raw to functionalized SWNTs are blended into the silicone elastomer matrix at a total loading of 0.5 percent by weight, a target real permittivity value can be obtained between 70 and 3. This has particular use for designing materials for microwave lenses, microstrips, filters, resonators,...
Topics: NASA Technical Reports Server (NTRS), CARBON NANOTUBES, COMPOSITE MATERIALS, NANOTUBES,...
No abstract available
Topics: NASA Technical Reports Server (NTRS), INTERNATIONAL SPACE STATION, CAMERAS, WIRELESS COMMUNICATION,...
Thermal barrier coatings of yttria stabilized zirconia and zirconia-ceria mixtures were deposited by RF reactive sputtering. Coatings were 1-2 mils thick, and were deposited on copper cylinders intended to simulate the inner wall of a regeneratively cooled thrust chamber. Coating stoichiometry and adherence were investigated as functions of deposition parameters. Modest deposition rates (approximately 0.15 mil/hr) and subambient sustrate temperatures (-80 C) resulted in nearly stoichiometric...
Topics: NASA Technical Reports Server (NTRS), PROTECTIVE COATINGS, ROCKET ENGINE CASES, SPUTTERING, THRUST...
An S-band radio frequency subsystem is described including two transmitters, two receivers and two antennas. The subsystem is capable of connecting either transmitter or receiver to either antenna while permitting simultaneous operation of a transmitter and a receiver. Circulator switches provide selection of a specific transmitter and receiver for connection to either a high gain or low gain antenna. Transmitter output filters, receiver input filters, and diplexers are combined to prevent...
Topics: NASA Technical Reports Server (NTRS), RADIO EQUIPMENT, RADIO FREQUENCIES, REDUNDANCY, SPACE...
During extravehicular activity (EVA), communications between the EVA astronaut and the space shuttle orbiter are maintained by means of transceiver installed in the environmental support system backpack. Onboard the orbiter, a transceiver line replaceable unit and its associated equipment performs the task of providing a communications link to the astronaut in the extravehicular activity/air traffic control (EVA/ATC) mode. Results of the acceptance tests that performed on the system designed...
Topics: NASA Technical Reports Server (NTRS), AIR TRAFFIC CONTROL, EXTRAVEHICULAR ACTIVITY, SPACE...
Ultrasonic radio frequency tone-bursts are launched into a sample of material tested. The amplitude of the tone-bursts and the slope of the resulting static displacement pulses are measured. These measurements are used to calculate the nonlinearities of the materials.
Topics: NASA Technical Reports Server (NTRS), ACOUSTIC PROPERTIES, PULSED RADIATION, SOUND WAVES, STATIC...
A versatile large-signal, two-dimensional computer program is used by NASA to model coupled-cavity travelling-wave tubes (TWTs). In this model, the electron beam is divided into a series of disks, each of which is further divided into axially symmetric rings which can expand and contract. The trajectories of the electron rings and the radiofrequency (RF) fields are determined from the calculated axial and radial space-charge, RF, and magnetic forces as the rings pass through a sequence of...
Topics: NASA Technical Reports Server (NTRS), AXISYMMETRIC BODIES, CAVITIES, COUPLED MODES, MODELS, RINGS,...
A linear ion trap for frequency standard applications is provided with a plurality of trapping rods equally spaced and applied quadruple rf voltages for radial confinement of atomic ions and biased level pins at each end for axial confinement of the ions. The trapping rods are divided into two linear ion trap regions by a gap in each rod in a common radial plane to provide dc discontinuity, thus dc isolating one region from the other. A first region for ion-loading and preparation fluorescence...
Topics: NASA Technical Reports Server (NTRS), BIAS, FEEDBACK CONTROL, FREQUENCY STANDARDS, ION STORAGE, ION...
This article studies, by computer simulations, the performance of deep-space telemetry signals that employ the pulse code modulation/phase modulation (PCM/PM) technique, using nonreturn-to-zero data, under the separate and combined effects of unbalanced data, data asymmetry, and a band-limited channel. The study is based on measuring the symbol error rate performance and comparing the results to the theoretical results presented in previous articles. Only the effects of imperfect carrier...
Topics: NASA Technical Reports Server (NTRS), CHANNELS (DATA TRANSMISSION), COMPUTERIZED SIMULATION, DATA...
This report documents the efforts and progress in developing a 'system-level' integrated circuit, or SLIC, for application in advanced phased array antenna systems. The SLIC combines radio-frequency (RF) microelectronics, digital and analog support circuitry, and photonic interfaces into a single micro-hybrid assembly. Together, these technologies provide not only the amplitude and phase control necessary for electronic beam steering in the phased array, but also add thermally-compensated...
Topics: NASA Technical Reports Server (NTRS), ANTENNA ARRAYS, INTEGRATED CIRCUITS, MICROWAVE CIRCUITS,...
A number of anomalous gravitational effects have been reported in the scientific literature during recent years, but there has been no independent confirmation with regard to any of these claims. Therefore, the NASA Marshall Space Flight Center, in response to the propulsion challenges specified by NASA's Breakthrough Propulsion Physics (BPP) program, proposed to explore the possibility of observing anomalous gravitation behavior through the manipulation of Josephson junction effects in...
Topics: NASA Technical Reports Server (NTRS), GRAVITATIONAL EFFECTS, GRAVITY ANOMALIES, HIGH TEMPERATURE...
Grit-blasted anode surfaces are commonly used in ion engines to ensure adherence of sputtered coatings. Next generation ion engines will require higher power levels, longer operating times, and thus there will likely be thicker sputtered coatings on their anode surfaces than observed to date on 2.3 kW-class xenon ion engines. The thickness of coatings on the anode of a 10 kW, 40-centimeter diameter thruster, for example, may be 22 micrometers or more after extended operation. Grit-blasted wire...
Topics: NASA Technical Reports Server (NTRS), ANODES, ION ENGINES, SPUTTERING, PLASMAS (PHYSICS),...
Systems and techniques for transmitting and processing an electrical signal through an opto-electronic system with an optical Brillouin amplifier.
Topics: NASA Technical Reports Server (NTRS), AMPLIFICATION, LIGHT AMPLIFIERS, RADIO FREQUENCIES,...
Large-aperture phased-array microwave antennas supported by membranes are being developed for use in spaceborne interferometric synthetic aperture radar systems. There may also be terrestrial uses for such antennas supported on stationary membranes, large balloons, and blimps. These antennas are expected to have areal mass densities of about 2 kg/sq m, satisfying a need for lightweight alternatives to conventional rigid phased-array antennas, which have typical areal mass densities between 8...
Topics: NASA Technical Reports Server (NTRS), ANTENNA ARRAYS, PHASED ARRAYS, SYNTHETIC APERTURE RADAR,...
The Interactive Coverage Analysis Tool (iCAT) is an interactive desktop computer program serving to (1) support planning of coverage, and management of usage of frequencies, of current and proposed radio communication systems on and near the International Space Station (ISS) and (2) enable definition of requirements for development of future such systems. The iCAT can also be used in design trade studies for other (both outer-space and terrestrial) communication systems. A user can enter the...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, INTERNATIONAL SPACE STATION, RADIO...
Presentation covers these issues: (1) Vehicles of the Launch Services Program, (2) RF Environment, (3) Common EMC Launch Vehicle Payload Integration Issues, (4) RF Sensitive Missions and (5) Lightning Monitoring,
Topics: NASA Technical Reports Server (NTRS), ELECTROMAGNETIC COMPATIBILITY, LAUNCH VEHICLES, RADIO...
The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) is performing communications systems research for the Unmanned Aircraft System (UAS) in the National Airspace System (NAS) Project. One of the goals of the communications element is to select and test a communications technology for the UAS Control and Non-Payload Communications (CNPC) link. The GRC UAS Modeling and Simulation (M/S) Sub Team will evaluate the performance of several potential technologies for...
Topics: NASA Technical Reports Server (NTRS), PILOTLESS AIRCRAFT, COMMUNICATION NETWORKS, NATIONAL AIRSPACE...
Lincoln Laboratory and NASA's Goddard Space Flight Center have teamed to re-use an existing instrument platform, the CoSMIRCoSSIR system for atmospheric sounding, to develop a new capability in hyperspectral filtering, data collection, and display. The volume of the scanhead accomodated an intermediate frequency processor(IFP), that provides the filtering and digitization of the raw data and the interoperable remote component (IRC) adapted to CoSMIR, CoSSIR, and HyMAS that stores and archives...
Topics: NASA Technical Reports Server (NTRS), INTERMEDIATE FREQUENCIES, MICROWAVE SOUNDING, MICROWAVES,...
220
220
Jun 19, 2010
06/10
by
Testerman, M. K
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No Abstract Available
Topics: MASS SPECTROSCOPY, RADIO FREQUENCIES
308
308
Sep 20, 2010
09/10
by
Jaenisch, Holger M.; Johnson, R. Barr
texts
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A commercial pulsed sympathetic discharge laser has been characterized and modified for use as a potential lidar. This report summarizes the initial findings and modifications made to the baseline system. The new laser performance is then checked with theory and operational results are presented. The laser has inherent mode instability and high chirp. Several solutions were tried and their results are presented.
Topics: BIT ERROR RATE, SWITCHING CIRCUITS, TELECOMMUNICATION, CONTINUOUS RADIATION, MICROWAVE EQUIPMENT,...
588
588
Jun 9, 2011
06/11
by
Litvin, Faydor L.; Fuentes, Alfonso; Vecchiato, Daniele; Gonzalez-Perez, Ignaci
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The development of new types of planetary and planetary face-gear drives is proposed. The new designs are based on regulating backlash between the gears and modifying the tooth surfaces to improve the design. The goal of this work is to obtain a nearly uniform distribution of load between the planet gears. In addition, a new type of planetary face-gear drive was developed in this project.
Topics: FUEL TANKS, PASSENGERS, TRANSMITTERS, ELECTROMAGNETIC FIELDS, FAULT DETECTION, PORTABLE EQUIPMENT,...
The development of optical fibers, lasers, and mixers at optical frequencies has offered the hope that active methods can contribute to optical interferometry. Heterodyning, in particular, looks attractive, even though bandwidths are narrower than one would like at present; one might expect this limitation to lessen as technology develops. That expectation, unfortunately, is not likely to benefit interferometry at optical wavelengths because of the intervention of quantum mechanics and the...
Topics: NASA Technical Reports Server (NTRS), AMPLIFICATION, HETERODYNING, INFRARED RADIATION, NOISE...
The potential for interference between solar power satellites (SPS) and other Earth satellite operations was examined along with interference problems involving specific electronic devices. Conclusions indicate that interference is likely in the 2500 MHz to 2690 MHz direct broadcast satellite band adjacent to SPS. Estimates of the adjacent channel noise from SPS in this band are as high as -124 dBc/4 kHz and -100 dBc/MHz, where dBc represents decibels relative to the total power in the...
Topics: NASA Technical Reports Server (NTRS), ELECTROMAGNETIC COMPATIBILITY, ELECTROMAGNETIC INTERFERENCE,...
A class of reconfigurable microwave antennas now undergoing development comprise fairly conventional printed-circuit feed elements and radiating patches integrated with novel switches containing actuators of the microelectromechanical systems (MEMS) type. In comparison with solid-state electronic control devices incorporated into some prior printed microwave antennas, the MEMS-based switches in these antennas impose lower insertion losses and consume less power. Because the radio-frequency...
Topics: NASA Technical Reports Server (NTRS), MICROELECTROMECHANICAL SYSTEMS, RADIO FREQUENCIES, SWITCHES,...
At SRON we are studying the performance of a Goddard Space Flight Center single pixel TES microcalorimeter operated in an AC bias configuration. For x-ray photons at 6 keV the pixel shows an x-ray energy resolution Delta E(sub FWHM) = 3.7 eV, which is about a factor 2 worse than the energy resolution observed in an identical DC-biased pixel. In order to better understand the reasons for this discrepancy we characterized the detector as a function of temperature, bias working point and applied...
Topics: NASA Technical Reports Server (NTRS), ALTERNATING CURRENT, BIAS, CALORIMETERS, ELECTRIC POTENTIAL,...
Remote habitats are often densely packed - items necessary to sustain life - items necessary to conduct work center dot Inhabitant's time is often quite valuable, if not priceless. Resupply shipments can be infrequent and expensive. Inaccurate inventory knowledge can lead to unnecessary overstocking, which can lead to insufficient work and/or living volume. Not being able to find items when they are needed can present: - safety issues - morale issues. RFID technology has the potential solve a...
Topics: NASA Technical Reports Server (NTRS), SPACE HABITATS, INTERNATIONAL SPACE STATION, INVENTORIES,...
204
204
Jul 6, 2010
07/10
by
Rowe, W. S.; Winther, B. A.; Redman, M. C
texts
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A theoretical analysis and a computer program have been developed for the prediction of unsteady lifting surface loadings caused by motions of trailing edge control surfaces having sealed gaps. The final form of the downwash integral equation has been formulated by isolating the singularities from the non-singular terms and establishing a preferred solution process to remove and evaluate the downwash discontinuities in a systematic manner. Comparisons of theoretical and experimental pressure...
Topics: MEASURING INSTRUMENTS, PERFORMANCE, RADIO EQUIPMENT, SYSTEMS ENGINEERING, ELECTROMAGNETIC NOISE,...
218
218
Jun 9, 2011
06/11
by
Ciardo, Gianfranco; Tilgner, Marc
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We discuss how to describe the Markov chain underlying a generalized stochastic Petri net using Kronecker operators on smaller matrices. We extend previous approaches by allowing both an extensive type of marking-dependent behavior for the transitions and the presence of immediate synchronizations. The derivation of the results is thoroughly formalized, including the use of Kronecker operators in the treatment of the vanishing markings and the computation of impulse-based reward measures. We...
Topics: QUARTZ, CATHODES, LUMINESCENCE, ARGON PLASMA, EMISSION SPECTRA, ELECTRIC POTENTIAL, STEADY STATE,...
Recent technology development activities for box truss structures and box truss antennas are summarized. Three primary activities are discussed: the development of an integrated analysis system for box truss mesh antennae; dynamic testing to characterize the effect of joint free play on the dynamic behavior of box truss structures; and fabrication of a 4.5 meter diameter offset fed mesh reflector integrated to an all graphite epoxy box truss cube.
Topics: NASA Technical Reports Server (NTRS), ANTENNA DESIGN, COMPUTER AIDED DESIGN, COMPUTER PROGRAMS,...
A linear L-band solid state high power amplifier designed for the space segment of the Mobile Satellite (MSAT) mobile communication system is described. The amplifier is capable of producing 35 watts of RF power with multitone signal at an efficiency of 25 percent and with intermodulation products better than 16 dB below carrier.
Topics: NASA Technical Reports Server (NTRS), COMMUNICATION SATELLITES, LINEAR AMPLIFIERS, MSAT, POWER...
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265
Jun 11, 2011
06/11
by
Kittel, Peter; Salerno, Louis J
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A lightweight, high-efficiency (LWHE) pulse tube cryocooler (LHEC) has been developed through an Ames, Air Force, and TRW partnership. This cooler is designed to meet NASA's future requirements for zero boil-off (ZBO) propellant storage. Such ZBO systems will meet NASA challenges for developing reusable space transportation vehicles for both Earth-to-orbit and long-duration missions. In addition to ZBO, LWHE coolers can be used with heat exchangers for sizing In-Situ Consumable Production...
Topics: POSITION (LOCATION), PULSARS, SUPERNOVA REMNANTS, X RAYS, MORPHOLOGY, POINT SOURCES, RADIO...
