Impact of Non-ideal Channel Reciprocity for BeamForming

In Multiple Input Multiple Output (MIMO) system, the transmitter obtains channel state information (CSI) by channel estimation. Then the CSI can be used to generate weights of transmit BeamForming according to channel reciprocity. While in LTE system, the mis-match between the transmitter and receiver antenna of the UE and the channel estimation error of the eNB can make the channel reciprocity non-ideal. This paper analyzes and simulates the performance of the BeamForming with non-ideal channel reciprocity in LTE system. The conclusions can be easily applied for other BeamForming systems.