Calibration of the downlink and uplink channel responses channel response in a wireless MIMO communication system

摘要

Calibration of the uplink channel response and downlink channel response in a wireless MIMO communication system [MEANS FOR SOLVING PROBLEMS] Uplink and downlink is calibrated to deal with differences in the responses of the transmit and receive chains at the user terminal and the access point. In the initial calibration, the user terminal and the access point sends the uplink and the downlink MIMO pilot used to derive a channel estimate which includes the responses of the transmit / receive chains in question. Derived (a) and (b) the correction matrix based on the channel estimation values, to then be used by each user terminal and the access point. In subsequent calibration, one entity transmits a reference steered and MIMO pilots. Sending a first matrix based on the references that are the steering, transmission matrix of the second based on the MIMO pilot, and the other entity is, calibration error estimates of the error in (b) in (a) and each containing I derive (c) and the (d), matrix. (C) and (d), it can be adjusted iteratively based on the adaptive procedure to minimize the error in the transmission queue between the two. [Selection Figure Figure 2