Max-Ratio Relay Selection in Secure Buffer-Aided Cooperative Wireless Networks

Abstract

This paper considers the security of transmission in buffer-aided decode-and-forward cooperative wireless networks. An eavesdropper which can intercept the data transmission from both the source and relay nodes is considered to threaten the security of transmission. Finite size data buffers are assumed to be available at every relay in order to avoid having to select concurrently the best source-to-relay and relay-to-destination links. A new max-ratio relay selection policy is proposed to optimize the secrecy transmission by considering all the possible source-to-relay and relay-to-destination links and selecting the relay having the link which maximizes the signal to eavesdropper channel gain ratio. Two cases are considered in terms of knowledge of the eavesdropper channel strengths: exact and average gains, respectively. Closed-form expressions for the secrecy outage probability for both cases are obtained, which are verified by simulations. The proposed max-ratio relay selection scheme is shown to outperform one based on a max-min-ratio relay scheme.

Dual Antenna Selection in Secure Cognitive Radio Networks

“…We note that it is common to assume high SNR in the physical layer secrecy systems to focus on the secrecy performance (e.g. [18], [21]). …”

Buffer-Aided Link Selection With Network Coding in Multihop Networks

“…Beside the aforementioned adaptive link selection, buffer-aided relays have also been used in applications including relay selection [10]- [13], cognitive radio networks [14] and physical layer network security [15]. Of particular interest is the maxlink relay selection scheme due to its excellent outage performance [10].…”

Using Buffers in Trust-Aware Relay Selection Networks With Spatially Random Relays

“…On the other hand, buffer-aided schemes have attracted much recent attention in many research topics, i.e., cognitive radio networks [7] and physical layer security [8]. In [9], [10], novel buffer-aided adaptive link schemes have been proposed for 3-node relay networks, and the work was extended to bidirectional 3-node relay work in [11], [12].…”