Outage Probability Analysis of RIS-Assisted Indoor Wide-FOV-VLC/RF Wireless Communication

A reflective intelligent surface (RIS)-assisted system design is proposed to improve the coverage of hybrid visible light communications (VLC)/radio-frequency (RF) indoor wireless communication. The VLC system utilizes a light-emitting diode (LED) as transmitter and a photo-detector as receiver. The data received by the photo-detector is further sent to the end-user via two RF links assisted by the RIS. The VLC channel is modeled considering two scenarios, where (i) the orientation of the receiver is random, and (ii) the location of the receiver is random. For these two scenarios, the closed/series-form expressions of the cumulative distribution functions (CDFs) of the instantaneous signal-to-noise ratio at the VLC receiver and the user end are derived. Utilizing the CDFs, the exact expressions of outage probabilities are obtained for both VLC channel models. Numerical results show that the ratio parameter (ratio of the radius of the photo-detector’s location to its perpendicular distance from the LED) is crucial in the performance of the considered system. Further, it is observed that the semi-angle of the LED and a ratio parameter play significant roles in the deployment of RIS-assisted VLC/RF indoor systems.