A secure optimal relay selection for full-duplex two-way relay network with two-sided eavesdroppers

This paper presents a novel full-duplex (FD) two-way (TW) decode-and-forward (DF) relay network with two-sided eavesdroppers, which includes two FD sources A B, multiple FD relays and two eavesdroppers. The two-sided eavesdroppers E1 and E2 are considered, and A, E1 are distributed in a same cluster different from the cluster of B, E2, which will lead a more complex eavesdropping environment. We propose an optimal relay selection (ORS) scheme based on maximizing secrecy capacity to improve the security performance of proposed system. The closed-form expression for secrecy outage probability (SOP) of the proposed FD-TW ORS scheme is derived by appropriately ignoring the interference imposed on the two eavesdroppers side. Furthermore, the impact of average signal-to-noise (SNR), number of relays (K) and the average residual self-interference imposed on full-duplex nodes are analyzed and simulations show that the proposed FD-TWR ORS scheme under better self-interference suppression scheme always outperform the traditional HD-TWR ORS scheme in terms of SOP performance.