Multi-stage partial PIC receivers for multi-rate DS-CDMA system with multiple modulation

In a multi-rate DS-CDMA system with multiple modulation, modulation format is adjusted according to the data rate of each user while symbol duration is fixed for all users. In this paper, two types of multi-stage partial parallel interference cancellation (PIC) receivers are considered for multi-rate DS-CDMA system with multiple modulation: multi-stage PIC receiver with partial cancellation factors and multi-stage PIC receiver with decision thresholds. Performance of the receivers is evaluated by simulation in a Rayleigh fading channel. It is shown that the multi-stage PIC receiver with partial cancellation factors achieves significant performance improvement over the matched filter (MF) receiver and has much lower symbol error rate (SER) than multi-stage PIC receiver for multi-rate DS-CDMA system with multiple modulation in a Rayleigh fading channel.