A Two-Hop Multi-Relay Secure Transmission with Improved Suboptimal Relay Selection Scheme

—This work studies the use of relay selection in reducing the capability of a hidden eavesdropper to intercept the confidential message transmitted between information source and legitimate receiver. Specifically, an improved version of the suboptimal selection with jamming scheme (SSJ) is proposed. To achieve a secure transmission system, we propose the choice of best relay node that will forward the confidential message only when the link quality of the selected relay terminal meets some predefined thresholds and the signal is transmitted with low power. The simulation results show that our proposed scheme can significantly improve the system performance in term of average secrecy throughput and intercept probability.