Rank Constrained Temporal-Spatial Filters for CDMA Systems with Base Station Antenna Arrays
O. Filiz, Aylin Yener · 2003
Abstract — In this paper, we consider a minimum mean-squared error (MMSE) based receiver structure which combines multiuser detection (temporal filtering) and receiver beamforming (spatial filtering). Motivated by the high complexity of the optimum receiver, we propose rank constrained temporal-spatial filters which are simpler and near optimum. An iterative algorithm based on alternating minimization is used to find the filter coefficients. The adaptive implementation, built upon least mean squares (LMS), is formulated and its convergence properties are investigated. I.