Security Analysis of A Mixed RF-FSO-VLC Triple Hop Cooperative Network

This research investigates a mixed radio frequency (RF)-free space optic (FSO)-visible light communications (VLC) cooperative relaying system that allows communication from an outside to an indoor system. In this case, the FSO link serves as a bridge between the core RF link and the last mile user communicating via the VLC link. In this paper, the RF and FSO connections are defined by the Nakagami-m and Malaga distribution respectively. The VLC link is based on geometrical modeling with intensity modulation (IM)/direct detection (DD). This paper analyzed the secrecy performance of the aforementioned system from a physical layer perspective. To do this, the secrecy outage probability (SOP) is derived and analyzed in closed form. The results are obtained by considering the different turbulence strengths and field of view (FOV) of VLC link. The outcomes are confirmed by the use of Monte Carlo simulations. The influence of system and channel characteristics on SOP performance is explored and addressed.