Date Added: Oct 2011
This paper considers the channel estimation for two-way relay MIMO OFDM systems. A Least Square (LS) channel estimation algorithm under block-based training is proposed. The Mean Square Error (MSE) of the LS channel estimate is computed, and the optimal training sequences with respect to this MSE are derived. Some numerical examples are presented to evaluate the performance of the proposed channel estimation method. Two-way relaying is an effective means to improve the spectral efficiency, where two source nodes can exchange information simultaneously with the help of a relay node. The main idea with two-way relaying is that each node can cancel the self-interference from its received signal to help decode the information from the other node.