A wireless data communication system simultaneously transmits data signals from more than one antenna with a deterministic, time-dependent phase difference between the signals. In one example, more than one antenna transmits the same data signal with a phase difference between the transmitted signals. In another example multiple users' data signals are simultaneously transmitted using a corresponding plurality of beams that each use at least two transmitting antennas. Transmissions to multiple users on a shared packet data channel can be scheduled at the same time. In one example, the phase difference is periodic and the beams are orthogonal to maximize system throughput even when one or more users is stationary or slowly moving.