The Design And Realization Of The Indoor Visible Light Communication System Based On High Power LED

The visible light communication refers to the realization of lighting and at the same time it takes into account the communication function, to achieve the integration of lighting and communication and to promote green lighting and communication, so it has a very broad application prospect. In order to explore the possibility of high power white LED’s lighting and communication, the paper designs the indoor visible light communication system based on high power white LED. Finally, the paper tests the performance of the system and provide experimental basis and theoretical reference for the future practical research of visible light communication technology based on high power white LED.The paper studies on the visible light communication technology research and development at home and abroad in recent years, particularly on the research of high-power white LED communication technology. It also introduces the communication system in the key technologies. The experiment selectes three different types of high-power white LED lights, respectively XLMPXML2, Puri VERO13 and CXA1304. According to the principle of the visible light communication system, the study focuses on the design of the three kinds of the transmission side circuit, and analyzes the circuit principle and parameter selection. The transmission circuit selects MOS tube driver drives serial work after the Comparison of three performance transmitter side of the circuit. The test results show that the transmitting end performance is good and the output voltage is essentially the same and the rising radical is small in 0-10 MHz signal frequency range. Then the paper designs and analyses the different sensitivity on the receiving end circuit, and uses the laser to test the bandwidth of different sensitivity receiving end circuit. The research builds the LED bandwidth test platform and measures that the 3dB bandwidth of the above-mentioned three kinds of high power white LED is not high, about up to a maximum of 2MHz.This experiment takes the LED of XLMPXML2 with the bandwidth of 2MHz and has a slowly high-frequency attenuation as the light source. According to the LED’s luminescent properties and the amplitude frequency characteristic, the research takes three types of XLMPXML2 white LED lamps series as a light source system and selects the more sensitive receiving circuit as the receiver, and finally builts the high power white LED indoor visible light communication system’s test platform. The test results show that the indoor visible light communication system based on high power white LED has a good performance with the successful implementation of the transmission distance with 2m, the receiving end illumination with 310 lx and the signal transmission rate with 2Mbit/s.In order to compensate the gain and improve the system’s bandwidth, the experiment adds equalization circuit after the receiving end circuit, and uses the Multisim software to complete the simulation. Finally, the bandwidth of the system increases to 5.5MHz. The experiments show that the indoor visible optical communication based on the high power white LED can be achieved, however, the communication rate is not high enough and needs the further study to improve the system bandwidth which can make the visible light communication system achieve commercialization.