Interference Mitigation for Multi Spot Beam Satellite Communication Systems Incorporating Spread Spectrum.

Nonlinear precoding techniques have robust transmit power stability and achieve superior interference suppression when compared to their linear counterparts. Tomlinson-Harashima Precoding (THP) is a suboptimal version of Costa's well-known work on writing on dirty paper (DPC). Implementing these precoding techniques in a multi spot beam satellite communications system that employs frequency reuse can significantly reduce co-channel interference (CCI). In this paper, we investigate and compare the performance of linear and nonlinear precoding techniques on the forward link of a multiple spot beam satellite link. In addition, we examine the potential benefits of integrating the novel spread spectrum (SS) technique with the existing precoding techniques. The new system's performance is evaluated and compared with that of standard precoding techniques, and the benefits of incorporating SS are weighed against the extra bandwidth requirements.