TRANSMITTER AND RECEIVER CALIBRATION FOR OBTAINING THE CHANNEL RECIPROCITY FOR TIME DIVISION DUPLEX MIMO SYSTEMS

摘要

A communication device operating in time division duplex (TDD) mode using multiple antennas is provided herein. The communication device uses receive channel estimation measurements to perform transmit beamforming and multiple input multiple output (MIMO) transmission, based on self-calibration of the various up/down paths via a method of transmission and reception between its own antennas, thus achieving reciprocity mapping between up and down links. Either user equipment (UE) or a base station may routinely perform this self-calibration to obtain the most current correction factor for the channel reciprocity to reflect the most current operating conditions present during TDD MIMO operation.