Simple relay selection criterion for general two-way opportunistic relaying networks

Presented is a simple two-way amplify-and-forward relay selection criterion for the more general case that all terminals´ transmit powers can be unequal, in which the optimal relay can be selected in a distributed manner requiring local channel knowledge and the terminals´ transmit powers, and a closed-form lower bound of outage probability is obtained over Nakagami-m fading channels. Simulation results show that the proposed scheme is outage-optimal.