On 3-D Hybrid VLC-RF Systems with Light Energy Harvesting and OMA Scheme over RF Links

In this paper, an indoor 3-dimensional (3-D) hybrid visible light communication (VLC)-radio frequency (RF) system with spatially random terminals is considered. Specifically, VLC and RF communications are employed over downlink and uplink, respectively. Meanwhile, the devices, like sensor nodes, are designed to harvest the energy from the light emitted by the light-emitting diode over the downlink, which is used for the transmissions over the uplink. The light energy harvesting model is proposed after introducing the line of sight propagation model for VLC. Then, the outage performance for orthogonal multiple access (OMA) scheme over the uplink has been studied by using stochastic geometry theory, while considering all devices are spatially random distributed in the 3-D room and all uplinks follow independent/correlated Rician fading. Finally, the analytical expressions for the outage probability with OMA scheme are derived and verified through Monte Carlo simulations.