In a multi-antenna, multicarrier transmitter, a multicarrier communication signal is generated by normalizing beamforming matrices based on an average subcarrier power loading for each of the transmit antennas. One or more spatial streams may be transmitted by two or more antennas. ...http://www.google.com.hk/patents/US20060120469?utm_source=gb-gplus-share專利 US20060120469 - Multiple antenna multicarrier transmitter and method for adaptive beamforming with transmit-power normalization
