Optimal Full-Duplex Relay Selection for Physical Layer Security in Cooperative Wireless Networks

In this paper, we investigate the full-duplex relay selection for physical layer security in cooperative wireless networks, where relays are working in decode-and-forward(DF) protocol. The optimal relay selection scheme which selects relay that maximizes the system secrecy capacity is proposed. Then, we derive the closed-form intercept probability expression of this scheme. As a comparison, we consider the traditional relay selection which selects relay that maximizes the source-relay-destination link's capacity without the existence of eavesdropper. And then, the numerical results show that the intercept probability performance of the proposed optimal relay selection is strictly better than the traditional relay selection. Besides, our analytic derivations are verified by Monte-Carlo simulations.