Energy-spectral Efficiency Tradeoff In Visible Light Communication Systems

Recent years,spectrum resources meet a shortage problem with the increasing number of mobile devices and the development of wireless communication.To solve this problem,people are exploring the high frequency positively.The visible light belongs to high frequency electromagnetic wave,and it has the potential to realize the communication function.The manufacturing process of LED is more and more mature,and the LEDs are massive produced,so LEDs are used commonly.Researches are trying to use LEDs as the transmitter and use the visible light as medium to communicate.It can combine the function of communication and illumination at the same time,and reduce the cost.What's more,VLC has good security performance and it can be used in electromagnetic sensitive scenarios.This paper makes an introduction about the project background,and makes a summary about recent progress at home and abroad.After that,this paper illustrates some basis of VLC,mainly about the component of VLC system,OFDM and MIMO.Because VLC is a totally new kind of communication method,there is no perfect channel model for it.So we make some simulation about the VLC channel.Bysimulation,we can get the channel impulse response function of VLC.The energy consumed by communication cannot be ignored at this era.This paper makes a research about energy efficiency and spectral efficiency.In this area,there is no such research about energy efficiency and spectral efficiency in VLC.We try to solve this problem,and some tradeoff figures are given by analysis.What's more,we evaluate the performance of different LED layouts,because the layout affects VLC performance so much.At last,this paper concludes the work and makes a future plan.