Multi-stage interference cancellation in multi-rate DS/CDMA systems

We show that the one-stage IC scheme for M-level rectangular QAM can easily be extended to a multi-stage IC scheme. The performance of different single modulation systems, with equal throughput, is compared with systems employing conventional detectors and the single user bounds. In the analysis we consider two methods for handling multiple data rates, mixed modulation and parallel channels. These methods are analysed under the assumption of Rayleigh fading. The results show a considerable improvement in both performance, close to the single user bound, and capacity compared with systems employing a conventional detector