Patent ID: 8630267

Claim:
A method comprising: at a base station operating in a wireless network configured to serve wireless client devices, receiving at a plurality of antennas of the base station downlink sounding messages in corresponding downlink sounding frames, wherein each downlink sounding frame is appended to a separate downlink network traffic subframe that is transmitted by respective ones of a plurality of feeder stations operating in a wireless backhaul network, and wherein the downlink sounding frames are each allocated to a single feeder station in accordance with a time division scheme in which no two feeder stations transmit a downlink sounding message in the same downlink sounding frame; transmitting from the base station uplink sounding messages in a particular one of a plurality of uplink sounding frames, wherein each uplink sounding frame is appended to a separate uplink network traffic subframe, and wherein the uplink sounding frames are each allocated to a single base station in accordance with the time division scheme for uplink sounding to feeder stations; generating spatial signature information with respect to a serving feeder station for the base station based on downlink sounding messages received from the serving feeder station in downlink sounding frames designated for the serving feeder station; generating interference spatial signature information based on signals received during downlink sounding frames other than the downlink sounding frames designated for the serving feeder station; and based on the spatial signature information for the serving feeder station and the interference spatial signature information, generating interference nulling beamforming weights for use by the base station when transmitting uplink backhaul traffic signals to the serving feeder station and/or for use when receiving downlink backhaul traffic signals from the serving feeder station.