Co-Channel Interference Mitigation in Multiuser Systems with Unknown Channels

This paper studies signal detection in multiuser systems where the uncertainty is due to fading as well as a strong co-channel interference of the same form as that of the desired signal. In particular, unlike for the desired signal, no pilot for the interference signal is available for measuring its fading channel state. Still, the interference is a non-Gaussian process and treating it as Gaussian noise can lead to poor performance. We propose a joint channel estimation and interference mitigation scheme based on belief propagation. Simulation results show that the receiver performs significantly better compared to conventional receivers with linear channel estimation.