Secrecy rate analysis of dual-hop AF relay wiretap channel

Nanrun Zhou, Xun Chen, Chisheng Li +1 more

Meysam Mirzaee, Soroush Akhlaghi

丁飞, Song, Ai-guo +4 more

An amplify-and-forward(AF) dual-hop relay is proposed for secure communication within Wyner s wiretap channel.Based on an information-theoretic formulation,the average secrecy rate is characterized when two legitimate partners communicate over a quasi-static fading channel.Theoretical analysis and simulation results show that both cooperative strategies of average power scaling(APS) and instantaneous power scaling(IPS) are proved to be able to achieve information-theoretic security,and eavesdropper is unable to decode any information.

Feiwen Li, Yongming Wang

In this paper, we investigate secure communication for a dual-hop relay channel in the presence of an eavesdropper. A novel independent randomize-and-forward (IRF) strategy is proposed to enhance the secrecy performance, where the relay maps the decoded message to an independent message set then encodes the message by random-coding argument. For the discrete model, we establish the achievable rate-equivocation for the IRF strategy. For the Gaussian model, we derive the perfect secrecy rate of IRF strategy and compare it with decode-and-forward (DF), amplify-and-forward (AF) and noise-forwarding (NF) strategies. Theoretical analysis indicates that the relay's engagement of independent secure coding enhances the security of transmission. Numerical results also show the proposed IRF strategy can significantly improve the secrecy performance of the dual-hop relay channel in some cases.

Fang Dong, Nan Yang, Maged Elkashlan +2 more

In this paper, we propose two cooperative jamming protocols in two-hop amplify-and-forward (AF) wiretap channels: 1) jamming signal at the source (JSS) and 2) jamming signal at the relay (JSR). We apply optimal power allocation (OPA) between the useful signal and the jamming signal to maximize the secrecy rate for each of the protocols. A fundamental question to address is “Which cooperative jamming protocol is superior under OPA?” To this end, we evaluate the maximum secrecy rate of JSS and JSR for the general scenario of independent but not necessarily identically distributed fading with distinct average signal-to-noise ratios (SNRs) in the first hop, the second hop, and the wiretap link. We demonstrate that the strong first and second hops equally benefit the secrecy rates of JSS and JSR, when the wiretap link is weak. When the wiretap link is strong, the secrecy rate of JSR is superior to JSS.

Shweta Pal, Poonam Jindal