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OwnerJames C. Administrator of the National Aeronautics and Space Administration, with respect to an invention of Fletcher, Klaus G. Johannsen +2inventors
InventorsJames C. Administrator of the National Aeronautics and Space Administration, with respect to an invention of Fletcher, Klaus G. Johannsen, Samuel Sabaroff, Varice F. Henry
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The presence, frequency and amplitude of radio frequency interference superimposed on communication links originating from a terrestrial region and including a relay in a geostationary spacecraft are determined by pointing a narrow beam antenna on the satellite at the terrestrial region. The level of noise radiated from the region, in a predetermined frequency band of interest, to the antenna is measured at a terrestrial station that is usually remote from the region. Many of the measurements are performed in each of a plurality of frequency bands across the spectrum. Calibrating radio signals having a plurality of predetermined EIRP's (Effective Isotropic Radiated Power) and frequencies in the spectrum are transmitted from the region through the spacecraft narrow beam antenna back to the station. At the station, the levels of the received calibrating signals are separately measured for each of the frequency bands and EIRP's. In response to comparisons of the measured amplitudes of like frequencies of the calibrating signals and noise, the presence, frequency and amplitude of sources of radio frequency interference originating from the region are determined.
A method of determining radio frequency interference with communication links including a celestial body and an artificial geostationary satellite of the body, said interference originating from the body, said links being in a predetermined spectrum, comprising the steps of:
A system for determining radio frequency interference with communication links including a celestial body and an artifical geostationary satellite of the body, said interference originating from the body, said links being in a predetermined spectrum, comprising a relay station on the satellite said relay station including a narrow beam antenna pointing at a predetermined region of the body establishing an uplink for said interference, a second antenna on the body for establishing a communication downlink between the satellite and an Earth station on the body, and means located at the satellite for frequency translating signals and transmitting said signals between the narrow beam antenna and the second antenna;
Dependencies are inferred from the claim text.