An algorithm for joint direction of arrival, time-delay and frequency-shift estimation in asynchronous DS-CDMA systems

A subspace based MUSIC type algorithm for joint direction of arrival (DOA), time-delay and frequency-shift estimation in asynchronous DS CDMA systems, which is based on spatio-temporal processing of signals received by an antenna array of generally non-uniform volume geometry is proposed. The proposed algorithm is near-far resistant, requires no preamble, and can be applied when orthogonality conditions is not perfectly satisfied. The algorithm can be used for both single user and multi-user estimation.