Source Performance And Modulation Technique Of Visible Light Communication System

Visible light communications (VLC) technology to transmit information through the modulated LED light source, combining this LED lighting and optical communications technology provides a new wireless transmission. This thesis analyzes a number of key technologies of the white LED communication system, more in-depth study on the performance of commercial white LED light source, including LED volt-ampere characteristic, the characteristics of the illumination and modulation bandwidth characteristics. Described the basic structure of the visible light communication white LED light source and type, provides a theoretical basis for visible light communication light source application.For the volt-ampere characteristic of the LED illumination features, design and implementation of experiments to measure and compare the performance of the various types of commercial LED. Focused on the white LED modulation receiver technology, designed and produced a white LED modulation driving circuit and receiving circuit. In order to accurately measure the LED modulation bandwidth characteristics, This thesis designed a VLC system as experimental platform, elaborate LED modulation bandwidth of the measurement principle and experimental process, and summarizes the problems encountered in the experiment and the corresponding solutions. Finally, summarize and draw conclusions, recommendations and outlook for the selection of the LED light source of visible light communication system in the future.