Performance of multi-rate single cell CDMA systems with linear successive interference cancellation

Successive Interference Cancellation (SIC) can effectively mitigate Multiple Access Interference (MAI) and improve the capacity of Direct-Sequence Code-Division Multiple Access (DS-CDMA) systems. In this paper, for the uplink of a single cell DS-CDMA system, the capacity limits of a conventional single-user detection receiver, a system with linear SIC receiver, and a system with perfect SIC are derived for an Addictive White Gaussian Noise (AWGN) channel. The results show that the linear SIC system can provide a much larger capacity compared with the conventional system in all cases. Moreover, with increasing of the number of the users in the system, the difference between the whole power of the perfect SIC and that of the linear SIC increases. So, if the perfect SIC is used to guide the power allocation, the resulting performance will be significantly worse than predicted.