Buffer-Aided Relay Selection for Wireless Cooperative Relay Networks with Untrusted Relays

Abstract

Wireless cooperative relay networks are widely used in various fields. Wireless channels are vulnerable to eavesdroppers because of the broadcast characteristics of wireless channels, the security problem of wireless cooperative relay networks needs to be solved urgently, and the trust level of relays is rarely considered in existing work. Therefore, the paper considers a wireless cooperative relay network with a passive eavesdropping node and untrusted relays and designs a trusted buffer-aided relay selection (TBARS) scheme based on the fact that the channel state information (CSI) of eavesdropping channel is hard to obtain. The paper uses the secrecy outage probability (SOP) to measure the security performance, derives the expression of the SOP based on Markov Process, and verify the feasibility of the TBARS scheme by simulations and analyzes the impact of various factors on the SOP of the TBARS scheme. Finally, the paper compares the TBARS scheme with max-link scheme in terms of the SOP, and the simulations demonstrate that the proposed scheme outperforms the other schemes.