基于白光LED的无线通信实验研究

Experimental Study of Wireless Communication based on the White LED

摘要:

对可见光通信系统收发端进行了研究, 采用分压限流式调制电路驱动LED, 以NJM4556AD运算放大器为核心器件作为接收端, 搭建了短距离可见光通信测试系统, 实验完成了50Hz~50kHz频率信号的有效传输, 通过优化接收端成功实现了语音信号的实时传输。实验表明, 随着频率的增加信号质量逐渐变差, 随着接收端偏离光源准直程度的增加, 接收功率逐渐变小, 甚至信号无法恢复, 并分析了影响信号恢复的主要因素, 优化电路后所传输的语音信号能够比较清晰地还原。实验结果对可见光通信的室内应用具有一定的参考价值。

Abstract:

The transceivers and receivers of visible light communication system are studied in this paper. The modulation circuit with separated voltage and limited current was used to drive the LED and the NJM4556AD operational amplifiers was used as the receiver, then a short distance visible light communication system was built. The effective transmission of the signal during 50Hz~50kHz was performed, and it realized the real-time transmission of audio signals by optimizing the receiver. The experimental results show that the signal quality becomes worse when the frequency increases and with the increase of the degree of the receiver off the light source collimation, the received power becomes smaller, which leads to the worse of the signal quality. The main factors affecting signal recovery are also analyzed, and the receiver gets the audio signal clearly after optimization.