Robust joint channel estimation and multiuser detection with differential modulation in DS/CDMA systems

Multiuser detection (MUD) is a powerful technique for mitigating the effects of multiple access interference (MAI) and near-far problems in DS/CDMA systems. However, most of the previous work on MUD assumes perfect channel information at the receiver. In this paper, we propose an effective joint channel estimation and data detection method with differential modulation and interference cancellation over slow varying fading channels. It is shown that we can achieve near one-user performance with few pilots. Furthermore, we show that the proposed receiver is near-far resistant. In particular, it is shown that the complexity of the proposed scheme is quite small and that it can be reliably used in relatively fast fading channels