The Study Of Channel Modle In Visible Light Communication System

As the rapid development of traditional radio frequency(RF)technology and less spectrum resource,visible light communication(VLC)has attracted much attention and inspired significant research activities.VLC emerges as the alternative communication technology method of RF,owing to many advantages of VLC,such as small size,reduced weight,long life,high brightness,steadily improved power efficiency and etc.In this paper,the illuminant,channel model and photo detector of VLC system are studied.In order to select the appropriate component of VLC system,the parameter of LED and Silicon PIN Photodiode are discussed.Based on the theory of photometry,a point to point VLC system is designed which contains receiving terminal and sending terminal.(1)Several basic theory of photometry for LED light source is studied for introducing its parameter.Then receiving sensor's parameter is described for component selection.(2)In this section two kinds communication channel link of visible light communication system is compared and analyzed.Based on the visible light theory of communication system channel model,the LED light source model is discussed and simulated(by Matlab)in detail.This paper offers an proposal to resolve the signal interference of VLC system which base on optical switches.(3)In this section a point to point visible light communication system is designed by using STM32F103ZTE6 as MCU,the PPM modulation method is selected as the modulation method.The sending terminal's driving chip is PT4115 which worked as LED driver chip and power supply.On the receiving terminal we choose the BPX 61 pin silicon photodiode detector that from OSRAM Company and low noise operational amplifier AD795 for signal amplification and filtering.In final,we established a point to point visible light communication system.