Patent ID: 8831118

Claim:
A wireless communication system in which a transmitter and a receiver each having a plurality of antennas form a pair, and the transmitter performs beamforming at each transmit antenna to transmit a multicarrier signal, comprising: a channel matrix acquiring unit, implemented by receiver circuitry, configured to acquire at the receiver a forward channel matrix from the transmitter to the receiver for each sub-carrier; a channel matrix encoding unit, implemented by the receiver circuitry, configured to encode the forward channel matrix of each sub-carrier acquired by the channel matrix acquiring unit, by decomposition from signals represented in fixed-point form into a data part and an amplitude part each having a predetermined bit width, at the receiver; a channel matrix information delivery unit, implemented by the receiver circuitry, configured to deliver the encoded channel matrix information from the receiver to the transmitter; a transmit antenna weight acquiring unit, implemented by transmitter circuitry, configured to acquire a weight coefficient of each transmit antenna, by decoding the channel matrix information delivered from the receiver and further analyzing the decoded channel matrix information, at the transmitter; and a transmit beamforming unit, implemented by the transmitter circuitry, configured to perform beamforming by digitally weighting each transmit antenna on the basis of the acquired weight coefficient and changing a directivity of the antennas to perform data transmission from the transmitter, wherein the channel matrix encoding unit is configured to retrieve a first maximum value, which is a maximum value of channel matrix elements in all sub-carriers, in a plurality of levels, and determine the amplitude part and a normalization coefficient for normalizing each channel matrix element to the data part having the predetermined bit width, with respect to each sub-carrier on the basis of a ratio between a second maximum value as a maximum value of channel matrix elements in each sub-carrier and the first maximum value, and multiply each channel matrix element by the determined normalization coefficient to obtain the data part for each sub-carrier.