Research On Visible Light Communication And WiFi Fusion System

Visible Light Communication(VLC)has rich spectrum resources,no electromagnetic radiation,and high signal-to-noise ratio.Therefore,it has received more and more attention than traditional radio communication.The visible light communication technology represented by light-emitting diode(LED)has become the mainstream of research because of its low cost and low power consumption.However,visible light communication technology also has some problems to be solved: one of the main problems is that when the optical signal is transmitted indoors,the bit error rate will increase due to the multi-path effect.Another major problem is that the bandwidth of the LED lamp is limited.It is not easy to achieve high-speed communication.The multi-carrier modulation technology has a series of advantages such as high spectrum utilization,effective reduction of inter-symbol interference,good anti-channel loss,and effective attenuation of narrow-band interference caused by artificial light sources.Therefore,this modulation technique is also applicable to visible light communication.In this paper,the visible light communication system mainly uses white LED as the light source,which has the functions of illumination and communication,and also has the advantages of low energy consumption and low price.At the same time,the visible light communication system mainly uses Discrete Multi Tone(DMT)and channel equalization to realize high-rate transmission system.This paper first introduces the semi-physical simulation system of visible light communication using SystemVue software for remote control,completes the system construction and uses the system to verify the channel equalization communication algorithm,and realizes high-rate transmission;then introduces LabVIEW-based visible light real-time link and completes the construction of the system and writes the FPGA code in LabVIEW to complete the modulation and demodulation of the link.Finally,the WiFi is used as the uplink,and the visible light communication system is used as the downlink fusion system.Compared with the pure WIFI system,the fusion system can greatly improve the network performance.