Joint symbol, DOA and carrier offset estimation in DS-CDMA systems

Based on the ESPRIT-like method, a closed-form CDMA signal and DOA estimation approach without the knowledge of space-time channel and training sequence is presented in this paper. An auxiliary matrix is constructed by exploiting the special structure of the antenna array. The symbol vector and DOA are obtained from an eigenvalue-eigenvector pair of the auxiliary matrix even under imperfect carrier recovery. The carrier offset can be acquired easily by exploiting the finite alphabet property of the transmitted symbols. In comparison with conventional space-time linear multiuser detector, in which the knowledge of space-time channel is assumed known, the proposed method has the advantage of lower computation at the expense of little performance degradation. Finally, numeral simulations are presented