Ephemeris-Based Sum Capacity Enhancement in Multi-Satellite Communication Systems

This paper investigates the downlink (DL) sum capacity of multi-satellite communication systems with a large number of low earth orbit (LEO) satellites. We propose user terminals (UTs) that use only the ephemeris information of the desired satellite without a periodic channel estimation process for the receive beamforming. However, removing inter-satellite interference (ISI) perfectly is difficult without precise channel state information (CSI). We address this problem by proposing an ephemeris-based satellite selection algorithm to mitigate ISI and further enhance the sum capacity. Simulation results show that the proposed ephemeris-based multi-satellite communication system enhances the average sum capacity compared to the conventional perfect-CSI-based FDMA system without any signaling overhead.