Performance of parallel interference cancellation for CDMA in estimated fading channels with delay mismatch

The parallel interference cancellation (PIC) multiuser receiver is among the most interesting multiuser demodulators for practical mobile communication systems. Thus, the performance of the PIC multiuser receivers operating in frequency selective fading channels is evaluated in this paper. A decision-directed (DD) multiuser complex channel gain estimation based both on prediction and smoothing is applied. The impact of delay estimation errors on the bit error rate (BER) of the receiver in both channel coded and uncoded CDMA systems is evaluated. It is observed that a rather low standard deviation of delay estimation errors (⩽0.1) is required to obtain a robust receiver performance. If that is the case the performance of the PIC receiver is close to the known delay case, and superior performance can be obtained