Cooperative NOMA Based VLC/RF System with Simultaneous Wireless Information and Power Transfer

In this paper, we propose a novel Cooperative Nonorthogonal Division Multiple Access (NOMA) based Visible Light Communication (VLC)/Radio Frequency (RF) system with Simultaneous Wireless Information and Power Transfer (SWIPT). In the proposed system, the Near User (NU) not only receives information but also harvests the energy from the light signals emitted by LED. The harvested energy is then utilized by NU to forward the information to the Far User (FU) who cannot directly communicate with LED through RF channel. To support such cooperative multi-user transmission, NOMA is adopted. We analyze the outage performance of both NU and FU and discuss the impact of Power Splitting (PS) ratio on the performance. It was found through theoretical analysis and numerical results that one can trading off the outage performance of users through PS ratio. In addition, there exists the optimal design of PS ratio which can minimize the outage probability of users.