Groupwise serial multiuser detectors for multirate DS-CDMA

This paper presents the performance of groupwise successive interference cancellation (GSIC) in a DS-CDMA system with multiple data rates (multirate). The performance is evaluated both in AWGN and Rayleigh fading channels. In the GSIC scheme users with the same data rate are grouped and detected, using either a matched filter or a parallel interference cancellation (PIC) receiver, interference between the groups is cancelled in a successive order. The results show that in a multirate system the GSIC yields a better performance than the PIC receiver. Further a delay error of 0.1 T_c is found to be tolerable