Performance analysis of interference cancellation schemes for a DS/CDMA system under delay constraint

The performance of two adaptive multistage interference cancellation (IC) schemes for direct sequence code division multiple access (DS/CDMA) systems, successive and parallel IC schemes, is investigated under a fading channel. The performance analysis is strictly based on the analytical approach to provide a complete framework to predict BER performance and system capacity for the IC schemes under investigation. We further investigate the performance of the successive IC scheme subject to the delay constraint, which may be imposed typically on most speech and video applications. It has been shown that the successive interference cancellation (SIC) scheme is more resistant to fading than the parallel interference cancellation (PIC) scheme. Our analysis also demonstrates that the performance may be significantly improved by the groupwise successive interference cancellation (GSIC) scheme, which can be properly optimized to meet the given delay constraint.