Optimal Aggregation of RF and VLC Bands for Beyond 5G Mobile Services

The integration of Radio Frequency (RF) and Visible Light Communication (VLC) technologies has been considered an enabler to achieving the Key Performance Indicators (KPIs) in Beyond 5G (B5G). Apart from higher data rates for enhanced Mobile Broadband applications, Ultra-Reliable and Low-Latency Communications and massive Machine-Type Communications must be also supported. This poses notable challenges in the design of a mobile communication system that relies exclusively on the use of licensed RF spectrum. In order to cope with the requirements of B5G services, the complementary benefits that RF and VLC bands have in terms of communication bandwidth, signal propagation characteristics, and ultra-densification feasibility, can be exploited. For this purpose, this paper studies the performance of two integration approaches, namely RF - VLC selection (Layer-3 or network-layer) and RF-VLC aggregation (Layer-2 or MAC-layer). Based on the obtained simulation results, it is possible to conclude that RF - VLC aggregation outperforms RF - VLC selection in terms of data rate performance, especially when ultra-reliable communication services are required to connect a large number of user terminals placed in an indoor scenario.