The Design Of LED Visible Light Communication System Based On ARM

The rise of white LED lighting technology has promoted the development of optical wireless communication technology, meanwhile, the enlarging demands for broadband access make the RF spectrum a precious commodity, visible light communication (VLC) technology has begun to get more attention as a solution to this problem, and gradually become the research hotspot in the field of optical wireless communication. LED has the characteristics of high speed modulation, it can transmit information by modulating the optical power (intensity) and provide illumination at the same time.In this thesis, we study the visible light communication technology and design the visible light communication system based on ARM.Firstly, the thesis introduces the basic framework of VLC system, and builds the hardware platform based on the framework. Secondly, LED and processor which are core components of the system are described in detail, and each function module is given, including power supply module, amplifier module, driver module, transmit/receive module and filter module, etc. On this basis, a VLC system built on bare ARM machines is realized. The system is based on JEITA CP-1222 protocol which use 28.8kHz’s sub-carrier and four channels pulse position modulation (4PPM) to achieve the function of identification (ID) and data transmission. Moreover, in order to improve the scalability and applicability of the system, the thesis studies the development mode of ARM_linux to migrate the software functions of VLC system on the ARM_linux platform. Finally, a simple user interface is designed for testing. The test results verify the feasibility of the system.This thesis realizes the visible light communication system based on ARM and provides specific theoretical basis and rich result for visible light communication application research.