Beamforming for the multiuser detection with decorrelator in synchronous CDMA systems: Approaches and performance analysis

Antenna arrays have been considered to increase the capacity of the wireless communication systems. In addition to antenna arrays, the multiuser detection has been investigated for the efficient use of bandwidth in code division multiple access (CDMA) channels through mitigation of near-far effects and multiple-access noise limitations. We consider both the multiuser detection and antenna arrays. For the multiuser detection, we use the decorrelating detector. It is shown that the resulting system is less affected by strong interferences and has near-far resistance. Furthermore, it is observed that the decorrelating detector does not depend on the spatial cross-correlation. In the conventional detector, however, the performance degradation from the spatial cross-correlation is observed. (C) 1997 Elsevier Science B.V.