可见光色分复用通信系统研究与实验

Research and experiment on visible light color division multiplexing communication system

针对单色光通信不便用于照明、普通白光通信频谱利用率较低的问题,设计了一个可见光色分复用通信系统。该系统在保持发光二极管(LED)正常照明功能的同时,还具备信息传递功能。在发送端,采用3种具有固定波长的LED进行调制;在接收端,使用与发送端波长相匹配的窄带滤光镜来分离各个信道的光信号。分离后的光信号经由单片光电二极管转换成电信号,这些电信号再经过与预设阈值的比较后,被微控制器接收并解码。测试结果表明:接收端的窄带滤光镜能有效区分来自3个特定波长LED的广播信号;当发送速率低于50 kHz时,眼图效果良好,能够实现稳定的通信;但当发送速率提升至50 kHz以上时,图像会出现错误色块和偏移失真。

Aiming at the issues that monochromatic optical communication is not suitable for lighting and the frequency spectrum utilization of ordinary white light communication is low,a visible light color division multiplexing communication system is de vised.The system not only maintains the normal lighting function of the light emitting diode(LED),but also possesses the function of information transmission.At the transmitting end,three types of LEDs with fixed wavelengths are utilized for modulation.At the receiving end,narrow-band filters matching the wavelength of the transmitting end are employed to separate the optical signals of each channel.The separated optical signals are converted by a monolithic photodiode into electrical signals,which are then compared with a preset threshold and received and decoded by the microcontroller.The test results indicate that the narrow-band filter at the receiving end can effectively distinguish the broadcast signals from the three specific wavelengths of the LED.When the transmission rate is lower than 50 kHz,the eye image effect is favorable and stable communication can be achieved.However,when the transmission rate is increased to more than 50 kHz,images will present wrong color blocks and offset distortion.