Performance analysis of opportunistic amplify-and-forward two-way relaying in two-wave with diffuse power fading channels

This paper considers cooperative amplify-and-forwards (AF) two-way relay networks (TWRNs) with opportunistic relay selection (ORS) in two-wave with diffuse power (TWDP) fading channels. To investigate the system performance, we first derive an easy-to-computer approximated expression for the exact outage probability to reduce computational cost. Furthermore, we presented compact expressions for the asymptotic outage probability and asymptotic symbol error rate, which characterizes two factors governing the network performance at high signal-to-noise ratio (SNR) in terms of diversity order and coding gain. Additionally, based on the asymptotic outage probability, we determine the optimal power allocation solution between the relay and the sources to minimize the overall outage probability under the assumption that both the sources have identical transmit power. The correctness of the analysis is validated through Monte Carlo simulations. Our derived results can be applied to general operating scenarios with distinct TWDP fading parameters which encompass Rayleigh and Rician fading as special cases and arbitrary number of relays.