Patent ID: 7729333
Filing Date: 2010-06-01
Classification: H04B

Abstract:
1. A method for selecting a transmission target terminal in a zero-forcing beamforming algorithm in which a base station with multiple transmit antennas selects a predefined number N of downlink transmission target terminals using channel information received from a plurality of terminals with at least two receive antennas, comprising the steps of: broadcasting a pilot beam to all K terminals; receiving information about a channel capacity of each terminal from the terminals in response to the pilot beam; selecting a terminal with a largest channel capacity as an initial transmission target terminal; determining whether the number of currently selected terminals, i, is equal to the predefined number N; receiving a channel matrix of an associated terminal from the initial transmission target terminal if the number of currently selected terminals, i, is different from the predefined number N; computing a null space of the received channel matrix; broadcasting a null space beam based on the null space; and receiving information about channel capacities from remaining terminals except the selected transmission target terminal in response to the null space beam, and selecting a terminal with a largest channel capacity as a transmission target terminal based on the received information about the channel capacities from the remaining terminals.