Radio-frequency performance of an 85-ft ground antenna - X-band
Superhigh frequency performance of paraboloidal ground antenna for Deep Space Instrumentation Facility
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Superhigh frequency performance of paraboloidal ground antenna for Deep Space Instrumentation Facility
Airborne equipment for measuring X band scattering of earth surfaces
High power transferred electron effect devices for superhigh frequency oscillators
Small signal and saturation characteristics for X band cyclotron resonance oscillator, discussing device design and configuration
Superconducting cavity X band oscillator designed for study of stability and spectral purity dependence on temperature
Radio frequency performance appraisal of 210 foot ground antenna at X band
Analyzing pulse-by-pulse return signal from onboard X band telemetry system in RAM C-1 and C-2 payloads
Geologic analysis of X band radar mosaics of Massachusetts
VHF and X band telemetry attenuation by plasma sheath around hypersonic reentry vehicles
X-band target simulator with spectral purity for long radar echo pulses
Interpretations of microwave emission from Venus through experiments in which anomalous signals have been observed in X-band from glow discharges
Small frequency shift measurement method for X-band plasma-loaded cavities
Direct phase reading X-band radio interferometer for attitude control of Applications Technology Satellite-4
Gas ionization and plasma heating by high power microwaves using X-band and S-band frequency magnetrons
X-band swept frequency oscillator using Gunn diode and ferrite phase shifter
Pyrotechnically operated S-band helical antenna is developed in which helix is deployed subsequent to antenna placement. Antenna is small, lightweight, and novel in that deployable helix is used in place of fixed dish or horn. It can be designed to cover L- and X-band frequencies.
X-band (8910 megahertz) and C-band (4455 megahertz) measurements indicate that two domains exist in the variation of radar cross section with wind at incident angles far from the normal. The first domain for flow windspeeds is characterized by a rapid variation of radar cross section with wind and the second domain at higher windspeeds by an asymptotic approach to an upper limit (saturation). The transaction between the two domains occurs at a windspeed of approximately 10 knots. Recent Joint Ocean Surface Study I observations tend to confirm this observation and offer additional proof of the validity of a composite surface model which relates the radar cross section of the sea to the wave-height spectrum. This confirmation was obtained by comparing the radar cross section measured by the four-frequency radar system with the radar cross section calculated from the ocean wave-height spectrum that had been determined by the optical analysis of photographs taken at the same time. A possible explanation for the wind variation of the radar cross section of the open ocean also was evolved, based on radar measurements in a wave tank under various wind conditions and subsequent comparison with optically determined spectra.
Topical communication in the context of a deep space communication link. Communication link analysis at the optical frequencies differs significantly from that at microwave frequencies such as the traditional S and X-bands used in deep space applications, due to the different technology of transmitter, antenna, modulators, and receivers. In addition, the important role of quantum noise in limiting system performance is quite different than that of thermal noise. The optical link design is put in a design control table format similar to a microwave telecom link design. Key considerations unique to the optical link are discussed.