Patent ID: 7558330

Claim:
A method of partitioning transmit antennas in a radio system, said method being performed in a receiver in a first node communicating with a transmitter in a second node in the radio system, wherein multiple independent data streams are transmitted from subsets of a plurality of transmit antennas, said method comprising the steps of: determining for each transmit antenna, a co-phasing angle that maximizes the received signal power, said step of determining a co-phasing angle for each transmit antenna being characterized by: computing a prefilter weight matrix for each transmit antenna subset; computing a prefilter channel as a product of the prefilter weight matrix and a channel impulse response matrix; computing a trace metric of a prefilter channel autocorrelation matrix; maximizing the trace metric to decouple the input streams; and determining the co-phasing angles independently for each data stream; determining a partitioning of the plurality of transmit antennas that provides the highest channel capacity among all possible partitionings, wherein the step of determining a partitioning of the plurality of transmit antennas includes determining the number of transmit antenna subsets, which transmit antennas are included in each subset, and the capacity of the data stream to be transmitted from each transmit antenna subset; and providing to the transmitter, information regarding the determined co-phasing angle for each transmit antenna, and information regarding the transmit antenna partitioning such that the transmitter can partition the plurality of transmit antennas into mutually exclusive subsets in accordance with the determined partitioning information.