Fast and Efficient Adaptation Techniques for Visible Light Communication Systems

Beam steering visible light communication (VLC) systems have been shown to offer performance enhancements over traditional VLC systems. However, an increase in the computational cost is incurred. In this paper, we introduce fast computer-generated holograms to speed up the adaptation process. The new, fast, and efficient fully adaptive VLC system can improve the receiver signal-to-noise ratio (SNR) and reduce the required time to estimate the position of the VLC receiver. It can also adapt to environmental changes, providing a robust link against signal blockage and shadowing. In addition, an angle diversity receiver and a delay adaptation technique are used to reduce the effect of intersymbol interference and multipath dispersion. Significant enhancements in the SNR with VLC channel bandwidths of more than 26 GHz are obtained, resulting in a compact impulse response and a VLC system that is able to achieve higher data rates (25 Gbps) with full mobility in the considered realistic indoor environment.