Self-Interference Suppression for SatCom Active Antenna Arrays through Joint Transmit and Receive Beamforming

A novel joint transmit and receive beamformer algorithm to suppress self-interference (SI) in shared aperture full duplex active antennas for LEO user terminals is presented. The algorithm ensures regulatory radiation mask compliance while also maximizing realized gain for a given SI level. Simulation results for a 1024-element Vivaldi array at Ku-band illustrate the trade-off between achievable SI suppression and gain. In the absence of frequency diplexers or isolators, a total isolation in excess of 100 dB over scan angles of 5 degrees - 60 degrees is achieved, with an isolation of 5 dB at broadside, while the per-channel coupled power levels at the input of the LNAs are suppressed by 5 dB through transmit beamforming over the entire scan range.