Abstract: A system for interference suppression onboard a satellite may include an antenna that is configured to receive uplink signals from a ground-coverage area and to generate a first signal. A spot-beam antenna may be configured to receive interference signals and to generate a second signal. A processor may be configured to receive the first signal from the antenna and the second signal from the spot-beam antenna and to perform a cross-correlation to generate a composite signal that includes a null at an interference frequency. The antenna may be a shaped reflector antenna and the spot-beam antenna may be a parabolic reflector antenna.

Abstract: A radar system mounted on a moving vehicle uses a displaced phase center antanna (DPCA) and associated processing for taking the difference between the two signals received by the displaced antennas to provide moving target indication (MTI) by cancellation of the returns from stationary targets. The presence of moving targets is identified by threshold processing within discrete frequency bands. DPCA processing ordinarily results in amplitude nulls or "blind speeds" for targets moving at particular radial velocities. According to the invention, the two signals received by the displaced antennas are summed, weighted and divided into frequency bands which extend through the expected null region in a form of Doppler processing. Threshold processing is performed on DPCA processed signals within certain frequency bands outside of the null regions and on Doppler processed signals within other frequency bands, thereby substantially eliminating the blind speeds.