| 摘要 |
The purpose of the present invention is to reduce an overhead of channel sounding in unique mode transmission in a TDD-MIMO system. In a system in which at least one from among first and second wireless devices has a plurality of antennas and bi-directional transmission is performed by TDD, the present invention limits a transmission path from among all transmission paths between first and second wireless devices, sends a known signal in a time domain back for calibration to equalize features of bi-directional transmission of the limited transmission path, and calculates a calibration weight by using an obtained transmission path estimate value. In one embodiment, the second wireless device, which has received a signal including the known signal, simultaneously performs a plurality of calibrations by converting the received signal into one in a frequency domain, selecting only the known signal on a transmission path to be calibrated, then converting the selected signal back into one in the time domain, and sending the converted signal back. |
