Performance analysis of an efficient multipath delay estimation approach in a CDMA multiuser environment

In this paper, we introduce an efficient and simple technique for estimating closely-spaced multipath delays in an asynchronous multiuser CDMA systems. The subchip resolution is achieved via a nonlinear quadratic operator called Teager-Kaiser operator, which exploits the structure of the cross-correlation function between the received signal and the reference code. Simulation results in the presence of multiple interfering users and Rayleigh fading multipath channels are presented. It is shown that the proposed technique is near-far resistant, and its performance in the presence of closely spaced multipaths is much better compared to the peak tracking with subtraction method. Moreover, it has the advantage of a very simple implementation, compared to other maximum likelihood approaches