Channel Estimation and Training Design for MIMO-OFDM Two-Way Relay Systems
Communication based on relaying has been drawn a lot of attentions due to the potentials of extending the communication coverage, enhancing communication qualities. In conventional one-way relay systems, four time slots are needed to accomplish one information exchange process between two users. However, in two-way relay systems, only two time slots are needed to finish one information exchange process. In particularly, at the fist time slot or the first phase, both users send their information to the relay and at the second time slot or the second phase, the relay broadcasts the signals to both users after appropriate signal processing.