The Study Of Indoor Wireless Communication Based On White LED

Indoor visible light communication is a new type of wireless communication.Along with the rapid development of white LED, white LED lighting is graduallyreplacing the traditional way of lighting. Because LED is environment-friendly,efficient and energy-saving, that characteristics provide the material basis for indoorvisible light communication. Indoor visible light communication system, which notonly meet demand the needs with indoor lighting, but also provide indoor dataservices of wireless. There are many advantages in indoor visible lightcommunication, such as no-electromagnetic radiation, well secrecy, without need toapply spectrum resources, et.al. As one of indoor wireless communication, it not onlyintegrate lighting function and communication function in one system, but also meetsthe needs of data transmission of wireless in the area(such as aircraft cabin andhospital) that is electromagnetic radiation sensitive.This dissertation study the RGB-LED visible light communication system basedon WDM technology. Firstly,this dissertation illustrates and analyzes the structure ofthe white LED, light-emitting principle and the optical and electrical properties whenLED is working normally; Secondly, this dissertation explains the modulation, thechannel model, the noise model which are used in the dissertation, and gives a layoutthat based on the light intensity and received power. ISO (International Organizationfor Standardization) regulated indoor lighting intensity between300lx to1500lx inoffice lighting. So a design that can meet the high-speed data transmission and thelighting intensity does not less than300lx.In this dissertation, the writer used RGB-LED as lighting recourse, OOK-NRZ asmodulation, This design was applied WDM technology into visible lightcommunication system and gave a low cost light wireless communication system isdesigned and realized in this dissertation. The design frame is given, and analyzed,and explained the design and selection principle of each part. In the latter part of thedissertation, writer shows the simulation and test of the experimental platform. Aftertesting, the circuit transportation speed is50kHz at mono color and150kHz at threecolors. At last, analyzing and summarizing the experimental results, and posing thefuture research direction and indicate orientation of next step.