| 摘要 |
A transmitter beamforming technique for use in a MIMO wireless communication system determines a calibration factor and then applies the calibration factor to a transmit beamforming steering matrix developed using implicit beamforming, i.e., using an estimate of a forward channel disposed between a transmitter and a receiver based on a measurement of the reverse channel disposed between the receiver and the transmitter. The beamforming technique first determines descriptions of both the forward and reverse channels, determines an estimate of the forward channel from the description of the reverse channel, determines right singular matrixes which model the forward channel and the estimated forward channel and then develops a calibration factor from the determined right singular matrixes. The beamforming technique then applies the determined calibration factor to a steering matrix which is calculated using a standard implicit beamforming technique, i.e., assuming that the forward channel can be described as the transpose of the reverse channel. The use of this beamforming technique provides superior beamforming results when using implicit beamforming without having to take the necessary steps to determine a description of the actual forward channel each time a new steering matrix is to be calculated. |
