Outage Analysis of Full-Duplex Two-way DF Relaying with Joint Source and Relay Selection

Abstract

In this paper, we study the full-duplex (FD) two-way decode-and-forward (DF) relay system consisting of multi-source nodes, multi-relay nodes and one destination node. The numbers of sources and relays are $M$ and $N$ respectively. The direct links from the source nodes to the destination node are considered for reliable transmission. Each transceiver node operates on FD transmission mode, and is equipped with two antennas, one for transmission and the other for reception. On the basis of conventional selection schemes, we propose a low-complexity joint source and relay selection scheme, where the system adaptively selects the source node and the relay node to transmit information based on the instantaneous channel state information (CSI). The proposed selection scheme can realize $M+N$ diversity gain without requiring global CSI, where the source is selected based on the CSI of direct links and then the relay is confirmed by applying opportunistic relaying strategy under DF protocol. The performance evaluation of the proposed selection scheme is performed by outage probability in closed-form when residual self-interference (RSI) introduced by FD mode is considered. Furthermore, simulation results demonstrate the accuracy of all theoretical derivations, and simultaneously show the number of sources and relays, the transmit power and RSI have important effect on system performance.