Performance analysis of joint relay selection and power allocation protocol for two-way relaying networks

Abstract

The joint relay selection and power allocation (JRS-PA) protocol combines power allocation (PA) and relay selection (RS) very well for two-way relaying (TWR) networks. In order to explore the system performance of JRS-PA protocol, we study the outage probability and diversity-multiplexing tradeoff (DMT) of JRS-PA protocol in TWR networks. For the sake of obtaining an effective performance evaluation for outage probability over the entire signal-to-noise ratio (SNR) (or transmission power) region, we first obtain the upper-lower bounds. Due to the fact that the obtained lower bound (lower bound 1) is very close to the exact outage probability only in low SNR region, we obtain another lower bound (lower bound 2), which can be used to evaluate the performance well in high SNR. Simulations developed to validate the derived analytical results show that the approximation outage probability can be used well to evaluate system outage probability over the entire SNR region. In addition, the simulation results indicate that JRS-PA protocol can achieve lower outage probability than other two protocols.