SWIPT-Enabled Cooperative Wireless IoT Networks With Friendly Jammer and Eavesdropper: Outage and Intercept Probability Analysis

Physical layer security (PLS) and simultaneous wireless information and power transfer (SWIPT) in cooperative relaying have gained great interest as technologies for security and energy enhancement in Internet-of-Things (IoT) networks. In this work, we investigate PLS for a SWIPT-and AF-enabled cooperative wireless IoT system, consisting of one source, multiple energy harvesting (EH) relays, and one destination, in the presence of an eavesdropper that tries to overhear the confidential information. Furthermore, an EH-friendly jammer is deployed to transmit jamming signals aimed at the eavesdropper to improve the security system. In this context, a low-complexity, sub-optimal, but efficient relay selection method is proposed. More specifically, the relay is selected to convey information such that it has the best channel to the source. Based on the proposed system model, the performance analysis of the intercept probability (IP), asymptotic IP, and non-zero secrecy probability (NZSP) is analyzed by considering the time switching (TS)-based relaying strategy. Particularly, the exact closed-form expression of IP is achieved by applying modified Bessel function expansion. Monte-Carlo simulations are employed to corroborate the correctness and efficiency of our mathematical analysis. The time splitting factor a makes variations on the IP of about 3x as a ? [0.1, 0.8]. However, a dramatic reduction of the IP up to 317x is observed as a increases from 0.8 to 0.9.

Automated summary

In this research, a low-complexity but efficient relay selection method is proposed for a cooperative relaying system that supports simultaneous wireless information and power transfer. The performance analysis of the system is conducted by considering the presence of an eavesdropper and an EH-friendly jammer. Monte-Carlo simulations are used to validate the proposed method's correctness and efficiency.