Research Of The Design Of Multi-wavelength Visible Light Communication System And The Mobility Of UV Optical Communication System

In recent years,with the rapid development of communication technology,the traditional way of communication was restricted by some problems,such as spectrum resource,security and so on,so people have to seek a new way of communication to solve these problems.The optical wireless communication(OWC)combines both wireless communication and optical communication,as OWC provide the huge spectrum resource while leveraging the flexibility of the radio-frequency(RF)wireless communication,Meanwhile,OWC has many other advantages such as license-free operation,environmental protection,high-security and flexible deployment.As a result,it has important research value and vroad application prospects.Based on different working wavelengths,visible light communication(VLC)and ultraviolet communication(UVC)are the new optical communication technology which have been rised in recent years.According to different work styles,OWC can be divided into the line of sight model and non-line of sight model and the model between them.At present,the VLC and UVC communication are still in the initial stage,there are many problems need to be solve.For example,as the optical source of visible communication system,the bandwith of LED is less than 10MHz,which can't satify the high-speed communication purposes.Again,the study of the mobility of ultraviolet communication is rare.The solution to these problems have great significance to the pritical application and development of this technology.Based on the National Natural Science Fund,this paper focus on the design of multi-wavelength visible light communication system and the mobility of UV communication system,the work and innovation points are as follows:First,introduces the system structure and operating principle of VLC and UVC,summarying the technical characterisitcs and the research situation of these two different wavelength communication technology.Second,based on the problem that the visible light communication system transmission rate is limited by LED bandwidth,we design a multiple-wavelength visible light communication system plan based on RGB-LED,built the communication platform and completed the communication test.Third,in order to improve the system bandwith of VLC,we put forward the multi-transmitter single-receiver,multi-amplitude modulation plan,which used the power overlay of on-off keying singal to improve the spectral efficiency of VLC.Fourth,based on the research vacancy of UVC,we explore the influence of the mobility to UV communication system,and based on the experiment data,we calculated the average bit error rate of the UVC system in the process of moving.Fifth,in order to improve the mobility and flexibility of UVC system,considering the problem brought by multipath interference,the paper proposed a merging method named selective maximal ratio combining.