An array receiver which reduces complexity and cost by exploiting multiuser information in signals received from a plurality of transmitting users preprocesses (40) samples of antenna signals (x1, x2 . . . , xN) from the antenna elements (22/1, . . . , 22/N) to form basis signals (yO, . . . , yM) together having fewer space-time dimensions than the space-time dimensions of the combined antenna signals. The receiver processes and combines the basis signals to produce sets of estimated received signals (z0, . . . , zM), each for a corresponding one of the users. Each of the basis signals comprises a different combination of the antenna signals. The receiver combines the basis signals to provide a user-specific output signal, and periodically updates parameters of the filters (40/0, . . . , 40/M) used for deriving each particular basis signal such that each user-specific output signal will exhibit a desired optimized concentration of energy of that user's received signal as received by the array antenna.