摘要
当白光LED同时用于照明和通信时,如果接收机放大电路采用固定增益,则会出现在照明范围内不同位置接收信号强度变化较大而导致接收信号饱和或丢失,从而会严重影响通信性能。为了解决固定增益存在的问题,研究了用于可见光通信的自适应接收电路,电路理论带宽为30MHz,并进行了实验测量。在发射信号强度恒定时,接收机在距离LED 1.65m处纵向移动-0.15~0.45m或横向移动±0.85m时输出信号幅度可基本保持不变,从而可以保证在光覆盖范围内正常进行通信。
When white light source LED is used for both illumination and communication, the received signal intensity varies greatly at different positions within the illumination range for a receiver with fixed gain, resulting in the saturation or loss of the received signal, which may degrade the communication performance seriously. In order to solve the problem of fixed gain, an adaptive receiving circuit for visible light communication is studied. The theoretical bandwidth of the circuit is 30 MHz, and the experimental measurement is carried out. For a constant transmit power of LED, when the receiver is positioned 1.65 m from the light source, the variation of the amplitude is insignificant for communication in illumination zone if the receiver has a lateral shift in a range of-0.15~0.45 m or longitudinal movement in a range of ±0.85 m.
引文
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