Radio resource allocation to provide physical layer security in relay‐assisted cognitive radio networks

Abstract

In this study, the authors consider a cooperative communication framework based on one‐way and two‐way relays to provide secure communications for secondary users (SUs) within an orthogonal frequency‐division multiple access‐based underlay cognitive network. By proposing a radio resource allocation problem with the aim of maximising the secrecy sum‐rate of SUs and solving it, they show that the deployment of relays is vital to achieve a non‐zero secrecy sum‐rate. Also, the impact of two‐way relay in system performance improvement is clearly visible in comparison with one‐way relay such that it can roughly double the resulting system secrecy sum‐rate. The impact of different system parameters on the achievable secrecy sum‐rate for both one‐way and two‐way relays is also investigated and compared through simulations.