IMPROVEMENT OF THE PERFORMANCE OF LEOS SYSTEMS

The throughput performance of Low Earth Orbit Satellite (LEOS) communication systems is analyzed, with a focus on the impact of Multiple Access Interference (MAI) in a direct sequence spread spectrum (DSSS) network operating under a non-uniform traffic model. The study examines how MAI affects system efficiency and evaluates performance improvements for both Dense Traffic Satellites (DTS) and Sparse Traffic Satellites (STS). This paper investigates the performance of a CDMA-LEOS system designed for voice communication services. We will show that when CDMA is applied on the uplinks, traffic nonuniformity causes large differences in the signal qualities at succeeding satellites; a satellite above a heavily loaded (dense) traffic area has a low signal-to-interference ratio (SIR), while its neighbor satellites over lightly loaded (sparse) traffic areas have a high level of SIR. Various interference mitigation techniques, including advanced power control, adaptive coding, and interference cancellation strategies, are explored to enhance throughput performance. Simulation results demonstrate that optimizing these techniques significantly improves network reliability, reduces packet loss, and maximizes spectral efficiency under varying traffic conditions. The findings provide valuable insights into designing robust LEOS systems capable of handling dynamic traffic distributions while maintaining high service quality.