Successive Interference Cancellation for DS-CDMA Downlink/Uplink

Abstract

In this paper, we introduce two novel successive interference cancellation (SIC) algorithms for multiuser detection (MUD) in direct-sequence code-division multiple-access (DS-CDMA) systems. One is proposed for receivers in the downlink and the other for receivers in the uplink. The downlink SIC algorithm is a blind MUD which consists of two parts: estimating the signature sequences and amplitudes of interference users first, and then implementing the SIC detection. The uplink SIC algorithm is implemented by accurately estimating the amplitudes of each active user first and then performing the QR-decomposition based SIC. Simulation results show that the proposed algorithms are near-far resistant and outperform the conventional well-known SIC algorithms significantly.