Self-reference beamforming for DS-CDMA communication systems

In this paper, a self-reference beamforming algorithm, based on the inherent temporal redundancy structure presented by the spreading codes of Direct Sequence Code Division Multiple Access (DS-CDMA) systems, is proposed. It is derived from a novel perspective of chip level cross-correlation properties. The algorithm is shown to give the optimal solution in the sense of maximum Signal to Interference plus Noise Ratio (SINR). Block and adaptive approaches to solve the problem are given. The method is tested against the well-known Temporal Reference Beamformer (TRB) combined with a decision-directed approach, showing a performance similar to it, despite no side information is being used.