Evaluation of parallel interference cancellation with the advanced first-stage in Rayleigh-fading channels

Abstract

We introduce a modified interference cancellation scheme to overcome MAI (multiple access interference) in DS-CDMA. Among the ICs (interference cancellers), the PIC (parallel interference canceller) requires more stages to have the better BER, and the SIC (successive interference canceller) faces the problems of power reordering and large delays. To resolve these problems, we propose a modified interference cancellation scheme combining SIC and PIC. The proposed IC has improved the performance through the total received signal applied ranking method is fed into the initial stage. Its structure extracts the good characteristics because of the MAI removed from the input signal in the initial stage. The characteristics of the proposed system are as follows: (1) smaller delay, (2) the MAI in the strongest user signal is also reduced (unlike SIC), (3) it has a good BER performance using fewer stages (unlike PIC).