Secrecy performance analysis for the mixed RF/VLC cooperative relaying systems

Abstract

In this work, the authors consider the security performance for the mixed radio frequency link and visible-light link cooperative relaying system, where the relay has the energy collection ability and can extract the direct current part existing in the visible-light signal. Then, the relay uses the collected energy to demodulate the received visible-light signal and retransmit it through the radio frequency link. With this equipment, some analytical expressions of the average secrecy capacity and the secrecy outage probability are derived. Furthermore, the asymptotic expression is also derived to examine the influence of the various configuration parameters on the secrecy performance of the mixed relaying system. At last, some numerical and simulation results are given to verify the theoretical analysis. INTRODUCTIONVisible light communication (VLC) has recently received considerable attention as a promising technique in the 5G/6G wireless communication [1]. With the increasing demand for the wireless communication networks and limited spectrum resources, light emitting diodes (LEDs) are used as sources, and an optical signal operated in a visible light band with a large bandwidth is used as a carrier of information source to realize the information transmission. VLC has both lighting and communication functions, and achieves an effective, green, and promising technology to realize the last mile of wireless communication. VLC has been widely used in shortdistance, small-scale, and indoor wireless communication. Due to the above mentioned characteristics of VLC, the scope of VLC application is limited [2,3]. Fortunately, the wireless relay can solve these problems well. Meanwhile, the VLCbased relaying system can obtain larger link capacity and better coverage.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.