Hybrid RF and VLC Systems: Improving User Data Rate Performance of VLC Systems

A hybrid radio frequency (RF) and visible light communication (VLC) system is considered. A hybrid system with multiple VLC access points (APs) and RF APs is designed and compared. In indoor environments, VLC APs can provide very high data rates whilst satisfying illumination requirements, and RF APs can offer ubiquitous coverage. Even though very high throughput is supported by VLC APs, such coverage area may be spatially limited. This gives an opportunity to introduce a new small cell layer to current heterogeneous wireless networks, and it is referred as optical attocellular layer. However since VLC piggy-backs on the existing lighting infrastructure, it may not be possible to achieve full coverage. Hence in practical deployments, the spatial throughput distribution of standalone VLC systems should be augmented. In this context, RF APs can be used to improve the overall rate performance of the heterogeneous wireless system. In this study, the focus is on improving the per user average and outage throughput. It is assumed that the VLC system resources are fixed, and the study quantifies the spectrum and power requirements for a RF system, which after introduction to the VLC system, achieves better per user rate performance.