Hybrid Beamforming for Satellite Ground Stations in the mmWave Band

One promising approach to increase data rates in satellite communication systems is using millimeter-wave (mmWave) communications. Ground stations (GSs) with mmWave antenna arrays offer high signal gains and more flexibility than traditional parabolic antennas. However, design costs of mmWave systems do not allow for fully-digital antenna arrays, where each antenna has its own Radio-Frequency (RF) chain. Instead, hybrid beamforming architectures, combining digital and analog beamforming, are preferred. In this paper, we present a low-complexity hybrid beamforming algorithm for GSs that relies on the knowledge of the satellites directions. We benchmark the rate performance of this method in a multi-satellite Multiple-Input Multiple-Output (MIMO) scenario and provide a comparison with more complex hybrid beamforming design methods. Simulation results show that the performance of the proposed geometrical algorithm approaches the performance of more complex state-of-the-art methods. Moreover, we present an experiment using mmWave Software-Defined Radios (SDRs) to validate the geometrical hybrid beamforming approach.