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Results for “RF Measurement”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2007

Airborne RF Measurement System and Analysis of Representative Flight RF Environment

Environmental radio frequency (RF) data over a broad band of frequencies were needed to evaluate the airspace around several airports. An RF signal measurement system was designed using a spectrum analyzer connected to an aircraft VHF/UHF navigation antenna installed on a small aircraft. This paper presents an overview of the RF measurement system and provides analysis of a sample of RF signal measurement data over a frequency range of 30 MHz to 1000 MHz.

Koppen, Sandra V.↗
NASA NTRS2007

Airborne RF Measurement System (ARMS) and Analysis of Representative Flight RF Environment

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 package and measurement system can be quickly returned to service if needed by future projects requiring measurement of an RF signal environment or exploration of suspected interference situations.

Koppen, Sandra V.↗
NASA NTRS1978

An Orbiting Standards Platform for communication satellite system RF measurements

The Orbiting Standards Platform (OSP) is a proposed satellite dedicated to performing RF measurements on space communications systems. It would consist of a quasi-geostationary spacecraft containing an ensemble of calibrated RF sources and field strength meters operating in several microwave bands, and would be capable of accurately and conveniently measuring critical earth station and satellite RF performance parameters, such as EIRP, gain, figure of merit (G/T), crosspolarization, beamwidth, and sidelobe levels. The feasibility and utility of the OSP concept has been under joint study by NASA, NBS, Comsat and NTIA. A survey of potential OSP users was conducted by NTIA as part of this effort. The response to this survey, along with certain trends in satellite communications system design, indicates a growing need for such a measurement service.

Wallace, R. G.↗
NASA NTRS1980

Analysis of airborne RF measurements from U.S.A. urban areas

The paper presents in-situ, airborne survey radio-frequency measurements, which were made over the 400-1000 MHz range in May 1977 during the ASSESS-II Space Shuttle/Spacelab simulation aircraft flights. Measurements were made from altitudes of 10,000 to 33,000 feet with a downward-directed 70 deg wide, half-power beamwidth receiving antenna pattern. Channel occupancy percentages are given within a 50 MHz spectrum width, and continuous spectrum-scan measurements are presented for selected locations on the USA West Coast, showing the channel occupancy environment within the 806-890 MHz mobile-service band.

Taylor, R. E.↗
NASA NTRS1986

Techniques for using emitting probes for potential measurement in RF plasmas

Investigations of the effects of RF on plasma potential measurements with electron emitting probes and methods for interpreting data are presented. Techniques correspond to the floating and inflection point methods of single-emitting and differential emitting probes, respectively. A simple method of measurement of plasma potential fluctuations is given which makes use of time-averaged emitting probe I-V characteristics.

Wang, E. Y.↗
NASA NTRS2006

Radio Frequency (RF) Attenuation Measurements of the Space Shuttle Vehicle

Following the loss of Columbia, the Columbia Accident Investigation Board (CAIB) provided recommendations to be addressed prior to Return To Flight (RTF). As a part of CAIB Recommendation 3.4.1 - Ground Based Imagery, new C-band and X-band radars were added to the array of ground-based radars and cameras already in-situ at Kennedy Space Center. Because of higher power density considerations and new operating frequencies, the team of Subject Matter Experts (SMEs) assembled to investigate the technical details of introducing the new radars recommended a series of radio frequency (RF) attenuation tests be performed on the Space Shuttle vehicle to establish the attenuation of the vehicle outer mold line structure with respect to its external RF environment. Because of time and complex logistical constraints, it was decided to split the test into two separate efforts. The first of these would be accomplished with the assistance of the Air Force Research Laboratory (AFRL), performing RF attenuation measurements on the aft section of OV-103 (Discovery) while in-situ in Orbiter Processing Facility (OPF) 3, located at Kennedy Space Center. The second would be accomplished with the assistance of the National Institute of Standards and Technology (NIST) and the electromagnetic interference (EMI) laboratory out of the Naval Air Warfare Center, Patuxent River, Maryland (PAX River), performing RF attenuation measurements on OV-105 (Endeavour) in-situ inside the Space Shuttle Landing Facility (SLF) hangar, also located at Kennedy Space Center. This paper provides a summary description of these efforts and their results.

Scully, R. C.↗
NASA NTRS1984

Storm severity detection (RF)

Measurement of lightning location data which occur together with continental thunderstorms and hurricanes was examined, and a second phase linear interferometer was deployed. Electrical emission originating from tropical storms in the Gulf of Mexico were monitored. The time span between hurricane ALLEN (10 August 1980) and hurricane ALICIA (18 August 1983) represents the longest period that the United States has gone without hurricane landfall. Both systems were active and data were acquired during the landfall period of hurricane ALICIA.

Johnson, R. L.↗
NASA NTRS2000

RF Coupling into the Fuel Tank of a Large Transport Aircraft from Intentionally Transmitting Peds in the Passenger Cabin

An investigation was performed to study the potential for radio frequency (RF) power radiated from Portable Electronic Devices (PEDs) to create an arcing/sparking event within the fuel tank of a large transport aircraft. This paper describes the experimental methods used for measuring RF coupling to the fuel tank and Fuel Quantity Indication System (FQIS) wiring from PED sources located in the passenger cabin. To allow comparison of voltage/current data obtained in a laboratory chamber FQIS installation to an actual aircraft FQIS installation, aircraft fuel tank RF reverberation characteristics were also measured. Results from the measurements, along with a survey of threats from typical intentional transmitting PEDs are presented. The resulting worst-case power coupled onto fuel tank FQIS wiring is derived. The same approach can be applied to measure RF coupling into various other aircraft systems.

Nguyen, Truong X.↗
NASA NTRS1981

Measurement of RF lightning emissions

A lightning radio emission observation laboratory is described. The signals observed and recorded include HF, VHF and UHF radio emissions, optical signature, electric field measurements, and thunder. The objectives of the station, the equipment used, and the recording methods are discussed.

Lott, G. K., Jr.↗
NASA NTRS1989

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

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

Gatti, M. S.↗