Parallel and successive interference cancellation for MC-CDMA and their near-far resistance

Recently, multi-carrier code division multiple access (MC-CDMA) systems have been considered as potential candidates for next generation (4G) technology. Within this context, due to their good compromise between complexity and performance, multi-user interference cancellation (IC) techniques have been proposed as an effective solution in the receiver design, both for downlink and uplink transmissions; nevertheless actual results are far from being exhaustive. In this paper, a performance comparison of parallel (PIC) and successive (SIC) IC techniques is presented, investigating also the influence of user power levels in a near-far environment, under dispersive channel conditions. The impact of the choice of the single-user detection (SUD) technique used in PIC and SIC receivers is also considered. Moreover, results are presented for convolutionally-coded systems, decoded by both hard and soft-input decoding methods.