Residual energy based multi-relay selection and power allocation scheme in two-way relay network

In this paper, we have proposed a multi-relay selection and power allocation scheme for two-way relay network which aims to maximize the sum-rate of two-way relay system. First, to prolong network lifetime, a multi-relay selection strategy is proposed in which both channel state information (CSI) and remaining energy (RE) are considered. Next, a multi-relay power allocation algorithm based on convex optimization (MRPA-CO) is presented. To reduce the computational complexity, it can be divided into two steps: terminal nodes power allocation (TNPA) and relay nodes power allocation (RNPA). Simulation results indicate that the proposed relay selection strategy can significantly prolong network lifetime compared to other relay selection strategies which consider CSI only, and the MRPA-CO algorithm has great advantage over equal power allocation (EPA) on sum-rate in two-way relay network.