A total power minimization approach to relay selection for two-way relay networks

In this paper, we develop an optimal relay selection strategy for a two-way relay network consisting of two transceivers and multiple relay nodes. Our relay selection approach is based on finding the relay which results in the minimal power consumption in the entire network while ensuring the transceivers´ quality of services (QoSs), measured by their received signal-to-noise ratios (SNRs), are above certain given thresholds. We show that such a relay selection scheme yields a closed-form solution for power allocation among the two transceivers and the optimally selected relay.