Secrecy Performance Analysis of Hybrid RF/VLC Dual-Hop Relaying Systems

Abstract

In this article, the secrecy performance of a hybrid radio frequency (RF)/visible light communication (VLC) system is studied. In this hybrid system, the source node (i.e., Alice) transmits information to the relay node via the outdoor RF link. Nakagami-m fading and path loss are considered for the RF link. The relay node includes an outdoor component and an indoor component, which are connected by using a wired medium. The outdoor component receives and recovers information by using the decode-and-forward (DF) relaying scheme and then transmits it to the indoor component. The indoor component then converts the received electrical signal into an optical signal by using a light-emitting diode. A legitimate receiver (i.e., Bob) deployed on the floor receives the optical signal. An eavesdropper (i.e., Eve) deployed in the RF or VLC link wiretaps the confidential information. In this study, we use the secrecy outage probability (SOP) and the probability of strictly positive secrecy capacity (SPSC) to evaluate the system performance. We then obtain the closed-form expression for a lower bound on the SOP and an exact closed-form expression for the probability of SPSC when the RF and VLC links are wiretapped, respectively. Numerical results are presented to validate the accuracy of our derivations. We further discuss the effects of the noise standard deviation, the equivalent threshold of the signal-to-noise ratio, and the floor radius on the system secrecy performance when the VLC link is eavesdropped upon. For the case when the RF link is eavesdropped upon, the impacts of the distance between Alice and the relay, the path loss exponent, the fading factor, and the distance between Alice and Eve on secrecy performance are also provided.

Mixed RF-VLC Relaying Systems for High-Speed Rail Communication

“…PLS has been extensively analyzed in literature for various relay-based dual-hop communication systems such as mixed RF-FSO, FSO-RF, RF-VLC, and VLC-RF, as evidenced by numerous studies [30][31][32][33][34][35][36][37][38][39]. Specifically, [30] and [31] proposed simultaneous wireless information and power transfer (SWIPT) based dual-hop mixed RF-FSO and mixed FSO-RF systems, respectively, utilizing power splitting methods and investigating the impact of SWIPT parameters on secrecy performance.…”

“…Specifically, [30] and [31] proposed simultaneous wireless information and power transfer (SWIPT) based dual-hop mixed RF-FSO and mixed FSO-RF systems, respectively, utilizing power splitting methods and investigating the impact of SWIPT parameters on secrecy performance. On the contrary, several studies [32][33][34][35][36][37] have concentrated on analyzing the secrecy performance of RF-VLC and VLC-RF systems. In [32], a dual-hop mixed RF-VLC system was examined under two scenarios: RF-side and VLCside eavesdropping attacks.…”

“…On the contrary, several studies [32][33][34][35][36][37] have concentrated on analyzing the secrecy performance of RF-VLC and VLC-RF systems. In [32], a dual-hop mixed RF-VLC system was examined under two scenarios: RF-side and VLCside eavesdropping attacks. Closed-form expressions for the secure outage probability (SOP) and strictly positive secrecy capacity (SPSC) were derived.…”

“…High-Speed Train (3) Different from [24][25][26][27][28][29][30][31][32][33][34][35][36][37], a relay-based mixed RF-VLC system for HSTs is studied in this work, in which the SOP is derived for end-to-end SNR of the BS-relay-UE link. The results in our work are presented for both assumptions of RFside and VLC-side eavesdropping attacks.…”

Energy-Efficient Trajectory Optimization for UAV-Based Hybrid FSO/RF Communications with Buffer Constraints

“…In such systems, both the advantages of RF and FSO links can be exploited. For terrestrial static relaying systems, end-to-end performance has been well analyzed [ 2 , 3 , 4 ]. However, only a few studies focus on hybrid FSO/RF systems with UAV mobile relays.…”