Mitigating error propagation in multiple access relay channels

Network coding has recently received significant attention as an innovative approach that improves the spectral efficiency of wireless communication systems. The multiple access relay channel (MARC) where multiple users communicate with a common destination via a relay, is one of the important network coding applications in wireless cooperative communications. In this paper, selective relaying (SR) and maximum likelihood (ML) detection approach which combat performance degradation due to error propagation in digital relaying based wireless networks have been applied to the MARC model. Simulation results for Rayleigh fading channels show that both SR and ML detection schemes outperform the noncooperative system that involves direct transmissions and overcome the diversity gain reduction due to error propagation.