摘要
脉冲位置调制是室内可见光通信的主要调制方式之一,它具有功率利用率高,频带利用率好,抗干扰性强的特点。为实现室内大功率白光LED照明通信,在分析PPM的原理基础上提出了一种改进的调制方式,给出了这种PPM符号的结构,并设计了大功率LED的驱动电路。其主要特点是由单片机直接输出帧同步信号加PPM信号,不设置保护时隙,其利用LED不发光的位置信息传输信号。实验结果表明该PPM调制方式能兼顾室内照明和通信功能。
Pulse position modulation（PPM） is the most popular modulation for indoor visible light communication with high power LED, which has the advantage of high efficient of power, low bandwidth and performance of anti-interference. In or- der to implement indoor visible light communication with high power LED as well as indoor lighting, the paper presents an improved PPM by analysis on the principle of regular modulator approach, and gives the scheme of the PPM symbol, also has designed the driving circuit of high power LED. Its main characteristics are directly output the PPM signal and the frame synchronization signal by microehip controller. There is no protection time slot, and transmits information without sending light pulse. The ex!0erimental results show that the PPM modulation can be lamination and communications.
出处
《光学与光电技术》
2011年第5期75-78,共4页
Optics & Optoelectronic Technology
关键词
大功率LED
脉冲位置调制
微处理器
LED驱动
high power LED
pulse position modulation
microchip controller
LED driving circuit
