Inter-symbol and Multi-user Interference Cancellation for LEO Satellite Systems

The orthogonal time frequency space (OTFS) scheme has been considered a promising technique to deal with high Doppler scenarios, where inter-user and inter-symbol interference are significant. Studying the low Earth orbit (LEO) satellite systems, in this work we propose a DD multi-feedback successive interference cancellation (DD-MF-SIC) detector with shadow area constraints (SAC) to enhance symbol reliability and mitigate error propagation. A multi-user uplink scenario is considered, where users transmit over independent sparse delay--Doppler channels and the classical block linear minimum mean square error (BLMMSE) detector is used as a baseline. Simulation results show that the proposed approach yields relevant bit error rate (BER) gains under relevant Doppler conditions, with a competitive computational cost.