Partial Parallel Interference Cancellation with Frequency Domain Equalization for Cyclic-Prefix CDMA Downlink

In this paper, we propose a hybrid receiver scheme called FDE-PPIC, which combines minimum-mean-square-error frequency domain equalization (MMSE-FDE) with multistage partial parallel interference cancellation (P-PIC), for the downlink of single-carrier cyclic-prefix code division multiple access (CP-CDMA) system over frequency-selective channels. MMSE-FDE instead of conventional RAKE receiver is utilized to alleviate the effect of frequency- selective channel and obtain the initial data estimation. Multistage P-PIC in frequency domain is then employed to mitigate the residual multiuser interference (MUI) for further improving the system performance. Simulation results show that the proposed receiver scheme can achieve better bit error rate (BER) performance than MMSE-FDE and FDE-PIC which is a combination of MMSE-FDE and multistage PIC.