Blind adaptive linear multiuser detection for multirate CDMA systems

A model is developed for variable-spreading-factor (VSF) multirate DS-CDMA in an AWGN channel. A blind adaptive decentralized linear multiuser detector for VSF CDMA is developed by applying constrained minimum output energy adaptation to a periodically time varying linear filter. The issue of detector periodicity determination when the receiver has no a priori knowledge of the data rates of the active users is addressed, and a novel algorithm based on the cyclostationary properties of the received signal is presented. Monte Carlo simulation results for the performance of the adaptive detector are given