Visible Light Communication Audio Signal Transmission System Design

LEDs have excellent modulation characteristics and enable illumination and transmission of audio signals simultaneously. A set of point-to-point visible light audio transmission system is constructed. The performance of the audio transmission system is studied by using the oscilloscope waveform. The influence of different transmission distance and receiving half angle on the amplitude value parameters are discussed. At the transmitting end, the audio signal transmitted by the MP3 player is amplified and stabilized by the amplifying circuit, the LED is driven, the electro-optical conversion is completed, the receiving end uses the photodetector for photoelectric conversion, and the signal is amplified and divided by the amplification filter and the low-pass filter. Finally get a saturated distortion-free audio signal. The results show that the system's ultimate transmission distance is 2m, and gradually decreases as the distance and the receiving half angle increase.