Abstract:

A blind detection algorithm for multi-user DS-CDMA systems is presented based on the parallel factor (PARAFAC) model. A novel orthogonal constrained PARAFAC-based blind receiver is proposed, which utilizes
orthogonality or semi-orthogonality of spreading code in DS-CDMA system. The Cramer-Rao bound (CRB) of the
orthogonal constrained trilinear decomposition is analyzed. Simulation results show that the orthogonal constrained trilinear alternating least square (OCTALS) algorithm has a lower CRB than traditional trilinear alternating least square (TALS) algorithm in processing DS-CDMA received signals. Compared with the traditional PARAFAC receiver, the OC-PARAFAC receiver has a better BER performance and faster convergence.

Key words: blind signal processing, parallel factor analysis, trilinear alternating least square, DS-CDMA, Cramer-Rao bound