SUCCESSIVE INTERFERENCE CANCELLATION FOR MULTIUSER ASYNCHRONOUS DS CDMA DETECTORS IN MULTIPATH-FADING LINKS/

In recent years, there has been an increasing interest in the use of c ode-division multiple access (CDMA) in cellular mobile and wireless pe rsonal communications, The choice of such multiaccess technique is att ractive because of its potential capacity increases and other technica l factors such as privacy and multipath rejection capabilities, Howeve r, it is well known that the performance of CDMA can be significantly degraded due to cochannel interference (CI) and the near-far effects, In this paper we consider the performance of direct-sequence (DS)-base d CDMA over fading channels that are modeled as slowly varying Rayleig h-fading discrete multipath channels, Specifically, we propose and ana lyze an adaptive multistage interference cancellation strategy for the demodulation of asynchronous us spread-spectrum multiple-access signa ls, Numerical results will show that the proposed multistage detector, which alleviates the detrimental effects of the near-far problem, can significantly improve the system performance.