Multiuser scheme for indoor visible light communications using RGB LEDs

In recent years, the rapid growth of visible light communications (VLC) is driven the interest into new applications of this technology. While single-user VLC systems are widely studied in the literature, less attention is given to multiuser scenarios which are likely to be deployed. Thus, this paper studies a new low-complexity multiuser structure for indoor VLC systems using RGB channels. In this scheme, a time-based approach is employed to separate the users´ signals which is combined with a three-dimensional signal constellation design to enhance the throughput on each user. The uncomplicated architecture of this multiuser system proves to be effective and appealing for low-cost implementations such as wireless sensor networks. Numerical simulations are carried out to evaluate the performance of the proposed scheme.