Low complexity frequency domain equalization for cyclic prefix CDMA systems

This paper presents four frequency domain interference cancellation receivers for the Single-Input Single-Output (SISO) as well as Single-Input Multiple-Output (SIMO) downlink CDMA systems. The proposed receivers employ an interference cancellation scheme to suppress the interference caused by the multipath fading channel. All filters in the proposed receivers are implemented in frequency domain. The performance of the suggested receivers is studied and compared to other traditional receiver schemes. The effects of channel estimation, and number of active users on the performance of the proposed schemes are also studied. The obtained results show a large performance improvement when using such an interference cancellation scheme in the receivers relative to the RAKE receiver, and frequency domain Equalization (FDE) only.