Interference Suppression and Electronic Tracking Using Antenna Arrays at Satellite Ground Stations

Abstract

Electronic beam steering via antenna arrays has the potential of replacing the mechanical steering at satellite ground stations. In this work, we exploit the benefits of antenna arrays at satellite ground stations combined with beamforming and direction-of-arrival (DOA) estimation techniques in combating interferences and compensating for erroneous knowledge of the spacecraft position. First, we propose two array geometries for the reception of payload data from lower earth orbiting (LEO) satellites at ground stations. Then considering a scenario where there exist cross-orbit spacecraft, the minimum variance distortionless response (MVDR) beamformer is employed to achieve the goal of the interference suppression and the reception of the desired signals. Moreover, by taking into account the potential errors in the a priori knowledge of the spacecraft flight path at lower elevation angles, we investigate the electronic tracking as a local refinement to compensate for these errors by resorting to DOA estimation techniques. Finally, numerical results demonstrate the advantages of employing antenna arrays in combination with signal processing techniques at satellite ground stations.