Analysis Of Ultraviolet Communication Network And Research On Led Communication System

UVC has the ability of NLOS transmission and other advantages,which has attracted widespread attention.However,with the increasing complexity of application scenarios,point-to-point communication has difficult to meet actual needs.Therefore,it is necessary to further study networking communication to make up for its short-distance limitation.Based on the background of UVC,this paper has carried out research on several technologies of UV networking communication.The main research work of this paper is as follows:1.Introduce a NLOS communication node model suitable for UVC network,and establishe a mathematical model for numerical analysis of its coverage.Then,by simplifying the calculation of the effective scatterer volume,the NLOS single-scattering channel model suitable for two nodes in the communication network is derived,and the path loss is compared with the Monte-Carlo model and the Luettgen model.Finally,based on the established model,the relationship curves of transmission distance,sending elevation angle,receiving elevation angle,transmitting beam angle,receiving field of view angle,path loss and bit error rate are analyzed.2.Through the overlapping area of the transmitting light cone and the receiving field of view,combined with the effective communication distance,the necessary conditions for two nodes in the communication network to be able to communicate are deduced.Through the analysis of the network coverage performance,the UV diamond communication network is designed and deduced:the effective coverage area expression of the diamond network,the expression of the maximum effective coverage area of a single node when completely seamless coverage,the expression of the minimum number of nodes required to achieve complete seamless coverage of the area.Considering the effective coverage area and connectivity,comparative analysis of the diamond network and the square network.3.The LED communication system is designed,and a circuit design scheme suitable for the communication system is proposed.The baseband signal transmission test of the system is carried out with a signal generator and an oscilloscope.The UDP transmission protocol is realized by FPGA,and the three-node data loop transmission test is completed.The research results show that the NLOS single-scattering channel model established in this paper has low accuracy in calculating the path loss when the communication distance is short,but as the transmission distance increases,the simulation results are basically consistent with the Luettgen model.When using this model for simulation,the amount of calculation will be greatly reduced.Considering the effective coverage area and connectivity,the diamond network can reduce the effective coverage area by 1.504%to increase its connectivity,while the square network has to reduce 21.083%of the effective coverage area to increase its connectivity.The UV LED communication system realizes baseband signal transmission with a frequency of 1MHz.The UDP transmission protocol implemented by the state machine uses the MAC address for matching detection to determine whether to receive data,which lays the foundation for network communication.