An adaptive PIC receiver with diversity combining for MC-DS-CDMA system

An adaptive parallel interference cancellation (PIC) receiver with pre and post diversity combining for the multi-carrier direct sequence code division multiple access (MC-DS-CDMA) system is presented and its performance investigated. By taking advantage of the combining techniques before and after the adaptive PIC stage, the diversity provided by the MC-DS-CDMA system can be exploited to improve further the bit error probability performance and increase the user/data capacity. Results show that this adaptive PIC receiver outperforms the conventional PIC receiver for MC-DS-CDMA systems. However, our studies reveal that this can only be achieved with the appropriate selection of the step size and the choice of initial weights, especially when the processing gain is low. Results also show that the advantage of using the adaptive PIC beyond the first stage of the multi-stage interference cancellation structure is only apparent when the level of MAI is high.