DefinePK

Abstract

A novel Selective Weighted Linear Parallel Interference cancellation (SWLPIC) technique is proposed to reduce the interference (degrading effect) on a desired user caused by other users sharing the same channel in a Multicarrier Code Division Multiple Access (MC-CDMA) system. The SWLPIC technique cancels the interference using WLPIC on selected users whose instantaneous Signal to Interference Ratio (SIR) exceed certain threshold on Rayleigh fading channels in each subcarrier. In WLPIC the multi access interference (MAI) are estimated and cancelled based on the soft outputs of individual subcarriers. The MAI estimate of individual subcarriers is scaled by a weight before cancellation. Also, the SIR for each subcarrier is determined and an expression for the optimum threshold is derived by optimizing the approximate expression for the SIR. The interference cancelled outputs of different subcarriers are then combined to form the final decision statistic. The simulation results show that the SWLPIC technique outperforms over matched filter (MF) detector and conventional Linear PIC (LPIC). Also the performance of SWLPIC approaches weighted LPIC (WLPIC).