Related Technology Research On Wireless Visible Light Communication

Visible light communication(VLC)is to load the information into LED and transmit it by the high-frequency flicker of LED,which is invisible to the human eye.Therefore,VLC can provide both illumination and communication at the same time.For underwater VLC,there are a large number of conductive media and dissolved substances in water,and the propagation of light beams in water will come in for great attenuation.Moreover,the phosphor LED,which is widely used at present,has only a modulation bandwidth of several megahertz,and its limited modulation bandwidth restricts the communication rate of the single-input-single-output(SISO)system.By using space-division multiplexing,multiple-input-multiple-output(MIMO)can improve the communication rate of the system.In addition,in recent years,many studies on VLC have been published,including Channel Modeling,High-Order Modulation,Multiple-Input and Multiple-Output and Multiple Access Schemes.Multiple Access Schemes are always of great significance in wireless communication systems.Based on above,the paper mainly has the following researches:Firstly,in order to promote the transmission performance of underwater VLC system,the schemes of underwater VLC system with multiple transmitters and receivers based on orthogonal frequency division multiplexing(OFDM)modulation are proposed and experimentally verified,including single-input and multiple-output(SIMO)and multiple-input and single-output(MISO).Secondly,in order to develop the excellent characteristics of interleaved division multiple access(EDMA)and OFDM,the paper proposes and verifies the uplink and downlink VLC multiple access scheme of IDMA-OFDM.