Multi-stage SIC structure for uplink UMTS multiuser receiver over multipath Rayleigh channels

This paper deals with uplink direct-sequence code division multiple access (DS-CDMA) transmissions over mobile radio channels. A new interference cancellation scheme for multiuser detection is presented. It is based on a modified multistage Successive Interference Cancellation (SIC) structure that enables efficient detection in multipath propagation environments, thanks to a single user RAKE combiner incorporated in each unit of the SIC structure. The behaviour of the suggested receiver is checked in the context of the Universal Mobile Telecommunication System (UMTS). Simulation results are presented for multipath flat fading Rayleigh channels. It is shown that the proposed detector is resistant to the near-far effect, and that small performance loss is obtained compared to the single-user bound.