短距离室外可见光数字传输系统研究

摘要

提出一种基于白光LED的短距离室外可见光数字传输系统,分析可见光室外通信信道特性及影响因素,采用恒流驱动电路实现亮度调节保证LED照度与通信稳定性,利用切换电路实现照明通信间切换,采用差分曼彻斯特编码来避免通信过程LED闪烁和保证光信号接收,并进行光路设计便于光路处理和干扰抑制.实验结果表明,系统实现了45 m室外可见光上无差错数字信号传输,工作稳定可靠且抗干扰能力强,为进一步研究室外可见光通信技术提供一定参考.%A novel short-distance digital transmission system based on white LED outdoor visible light communication is proposed.The characteristics of outdoor visible light communication channel and influence factors were analyzed in the paper.The constant current drive circuit were designed to ensure the illumination and communication stability of white LED.And the switch circuit to ensure switch between lighting and communication.The differential Manchester encoding was employed to avoid LED twinkle and guarantee the stability of signal receiving.The optical path design was adopted to optical processing and interference suppression.The measurement results shown that an error-free digital data transmission was achieved in the proposed system.And the system was not only stable and reliable, but also has high anti-interference ability, which also would have certain effective for further research on LED outdoor visible light communication.