Performance analysis for DS-CDMA systems with multistage HD-PIC

For a direct-sequence code division multiple access system with hard decision parallel interference cancellation (DS-CDMA with HD-PIC), we derive analytical results concerning the probability of a bit error. More precisely, we investigate the exponential rate H_k^(s) of a CDMA system with s stages of HD-PIC, with k users and processing gain equal to n, as n→∞. The rate is a good measure of performance and allows us to compare the performance after applying several stages of HD-PIC. Furthermore, we derive results for the asymptotic behaviour of the exponential rates H _k^(s) as k→∞. Finally, we investigate what happens when, for k fixed, we perform many stages of HD-PIC. These results can be used to guarantee a small BEP by applying a number of HD-PIC stages that depends on the number of users. The results show analytically that HD-PIC significantly improves performance. This conference paper is based upon and extends results and techniques of Van der Hofstad et al. (2000), that we briefly discuss