Statistical parallel interference cancellation over rayleigh fading channels with imperfect channel estimation

We study a reduced-complexity technique for partial parallel interference cancellation (PIC), in which PIC is performed only on the bits (blocks) with weak amplitudes. This technique employs a threshold at the matched filter outputs. We term our technique statistical PIC (STPIC), since the decision to employ PIC for any given user signal is based upon received signal statistics. Our proposed technique focuses on the system performance analysis with different thresholds. The system model is an asynchronous DS-CDMA system over a flat Rayleigh fading channel with imperfect amplitude estimation. Both analytical and simulation results have shown that our proposed receiver can maintain full PIC performance by performing IC on a substantially reduced percentage of bits when the threshold is appropriately chosen, thus significantly reducing computational complexity. Our method also provides a flexible means to meet different system performance requirements by setting the threshold appropriately.