Proposal of an interference cancellation receiver with low complexity for DS/CDMA mobile communication systems

The main targets of any direct-sequence code-division multiple-access (DS/C DMA) mobile communication system are to overcome the multipath fading influ ences as well as the near/far effect and to increase capacity. Many optimal and suboptimal detection approaches have recently been proposed and analyz ed in literature. Unfortunately, most of them share the drawback of requiri ng a complex implementation and do not represent a practical solution. This paper proposes a simple interference cancellation receiver for application s in DS/CDMA uplink communications. This receiver allows users to overcome the near/far effect and to enhance the system capacity. Differently from pr evious methods, the interference cancellation Is performed here on a one-sh ot basis. The performance of the proposed interference cancellation receive r is derived through computer simulations. However, a suitable analytical a pproach is also presented in the Appendix in order to evaluate the bit erro r rate (BER) performance in the particular case of synchronous users and tr ansmission channel affected only by an additive white Gaussian noise (AWGN) . The good behavior of the proposed approach is demonstrated by means of co mparisons in terms of BER performance and implementation complexity with th e classical Rake receiver and different multiuser receivers previously prop osed in the literature on this subject.