Channel Modeling Simulation And Measurement Performance Analysis Of Indoor MIMO Visible Light Communication System

Visible light communication(VLC),as a powerful supplement to wireless communication,utilizes abundant spectrum resources to increase the communication rate of the sixth-generation mobile communication network.Facing the 6G industrialization,the visible light communication field still faces some problems that need to be solved urgently,including: basic research work on the channel of visible light communication systems,and the development of analog front-ends in visible light communication systems.In order to increase the rate of visible light communication systems,multiple input multiple output(MIMO)technology is introduced,in indoor MIMO visible light communication systems,channel characteristic analysis is indispensable,and has an important impact on the system.Therefore,this paper uses simulation analysis,actual environment testing and other methods to study the characteristics of indoor MIMO visible light communication channels.The specific work of this paper is as follows:On the one hand,in order to understand the characteristics of the VLC system channel,this article investigates and summarizes the channel model methods of different VLC systems such as iterative method and ray tracing.Based on the advantages of zemax ray tracing,zemax software is used for the channel of the communication system is simulated and researched on indoor point-to-point visible light communication systems and MIMO visible light communication system.The power distribution is an index to measure the quality of communication service and user fairness,and the impulse response is an index to measure the channel.Therefore,the focus is on the analysis of the received optical power distribution and the impulse response of the channel.MIMO VLC Compared with the point-to-point visible light communication the simulation found that MIMO VLC system the received optical power distribution is more uniform,and the optical power of the receiver is related to the field of view(FOV)of the receiver.The larger the FOV,the higher the received optical power.In addition,the channel of the MIMO VLC system The impulse response is closely related to the distance of the receiver.The closer the distance between the LED array transmitter and the receiver,the higher the channel impulse response.This provides a reliable simulation analysis for the study of the channel characteristics of the MIMO VLC system in the actual indoor environment.On the other hand,since the actual visible light communication system is usually a multi-light source system,and there are factors such as ambient light interference,in order to further understand the propagation characteristics of visible light in the VLC system in the actual environment,this paper designs a MIMO VLC system hardware platform.First,a vector network analyzer was used to test the frequency response of the VLC system after pre-equalization,the frequency response was well compensated,and the communication performance of the designed VLC system was tested,and the system communication performance was good.Secondly,the luminous flux of the LED array light source of the indoor MIMO VLC system was tested using the integrating sphere,and it was found to meet the indoor lighting standard after the test.Finally,an indoor MIMO VLC system channel test environment was built,and a vector network analyzer was used to test the frequency response of the system's channels.The characteristics of the MIMO VLC channel are greatly affected by the design of the LED transmit array,the location of the transmitter and the receiver,and The correctness of the simulation is verified,and solutions are provided for the optimal design of the receiver and transmitter of the system.