A method for communicating a plurality of data streams between a
transmitting device with multiple transmit antennas and a receiving
device, is disclosed. The method comprises determining a list consisting
of a subset of the multiple transmit antennas on which the transmitting
device will transmit data, determining a set of power weightings,
providing the set of power weightings and the list of the subset of the
multiple transmit antennas to the transmitting device, weighting a
plurality of data streams by the power weightings, and transmitting the
power weighted data streams on the subset of the multiple transmit
antennas to the receiving device. Another aspect of the invention
comprises maintaining a codebook consisting of a plurality of transmit
weight vectors at both the transmitting device and the receiving device.
The method also comprises determining a list consisting of a subset of
the plurality of transmit weight vectors which to use for transmitting
the multiple data streams, determining a set of power weightings to be
use for each data stream, providing the set of power weightings and the
list of the subset of the plurality of transmit weight vectors to the
transmitting device, and weighting the data streams by the power
weightings and beamforming the data streams with the subset of the
plurality of transmit weight vectors.