Spotlighting for visible light communications and illumination

The trend toward solid state lighting with white LEDs has motivated much research for using these devices to provide wireless broadband data communications. Much work in this area has attempted to fit VLC into currently dominant indoor lighting modes, which broadcast the light in a wide field to achieve uniform coverage throughout a room. In this paper we explore spotlighting, which is appropriate lighting for many scenarios, as an alternative for implementing high datarate VLC. We find that spotlighting VLC has several benefits over uniform lighting implementations, including enabling higher datarate densities within a room and less channel distortion. We also introduce a hybrid scheme that combines spotlighting with uniform lighting to provide wide area data coverage as well as high-datarate "white hot spots" where needed.