Blind low-complexity code-timing acquisition for space-time asynchronous DS-CDMA signals

An adaptive near-far-resistant self-synchronizing detector for asynchronous DS-CDMA systems with a J-element antenna array is presented in this paper. The primary requirement is knowledge of the spreading-code sequence of the desired user. A low complexity version of the proposed detector is developed that utilizes the concept of the multistage reduced-rank Wiener filter introduced by Goldstein and Reed (1998). This results in a self-synchronizing detection criterion that requires no inversion or eigen-decomposition of a covariance matrix. It also achieves a rapid adaptive convergence under limited data support. Simulation results show that the proposed detector provides superior performance both as an increasing function of the size of the J-element antenna array and the amount of sample support.