Multi-User Interference Pre-Cancellation For Downlink Signals Of Multi-Beam Satellite System

Multi-user interference pre-cancellation is proposed in this paper for orthogonal frequency division multiple access (OFDMA) multi-beam satellite system to improve spectral efficiency as well as system capacity. Inter-beam interference model is demonstrated, and formulas of Carrier-to-Interference ratio (C/I) are presented, revealing severe co-channel interference among satellite beams. In order to reuse same channel among beams, Tomlinson-Harashima precoding (THP) is introduced to pre-cancel downlink interference of users from different beams, and its performance is analyzed.