2D multirate multistage PIC receiver for multicarrier DS-CDMA

In this paper, the scheme of it 2D multirate multistage PIC receiver for MC-DS-CDMA is proposed. In the considered MC-DS-CDMA system, the DS-CDMA signal transmitted on each OFDM subcarrier is a multirate signal that employs two layered spreading codes in a similar way to UNITS. The proposed 2D-PIC receiver takes into account the nature of the multirate signal transmitted to remove both the multiaccess interference (MAI) due to the lack of orthogonality between the CDMA codes and the intercarrier interference (ICI) due to loss of orthogonality between the subcarriers at the receiver. The receiver is designed to remove either ICI or MAI or both and to allow simple selection of the amount of each type of interference to remove at each stage. An analytical analysis of the receiver performance is done which helps to select the optimum configuration parameters of the receiver. Simulation results are presented to show the behavior of the proposed 2D-PIC receiver.