Patent ID: 8494073

Claim:
A method comprising: at a first communication device, receiving an uplink transmission at a plurality of antennas from a second communication device, wherein the uplink transmission comprises a plurality of uplink subbands; estimating an uplink spatial signature for each of the plurality of uplink subbands; determining a plurality of direction of arrival (DOA) components for each uplink subband from the uplink spatial signature; computing data representing a frequency-selective channel encompassing the plurality of uplink subbands between the first communication device and the second communication device that best matches the DOA components across the plurality of uplink subbands, the frequency-selective channel being represented by a set of continuous signal curves s l that best matches the respective DOA components u l (l=1, . . . , L) for each uplink subband, where L is the number of DOA components; computing a plurality of direction of departure (DOD) components for each of a plurality of downlink subbands based on the data representing the frequency-selective channel, the downlink subbands occupying a common communication spectral region with the uplink subbands: computing a downlink spatial signature for each downlink subband from the plurality of DOD components; and computing downlink beamforming weights for each of the plurality of downlink subbands based on the downlink spatial signature for beamforming a downlink transmission comprising the plurality of downlink subbands to the second device via the plurality of antennas of the first communication device.