Research On Wireless Ultraviolet Scattering Channel Characteristics Of The Haze And Soot

Ultraviolet(UV)communication with the important characteristics of non-line-of-sight(NLOS)scattering transmission is suitable for unmanned aerial vehicles(UAVs)formation perform secret communication tasks in complex environments.In the special environment such as battlefield,emergency,rescue and so on,there are usually different degrees of haze and soot.When the wireless UV transmits in the atmosphere,there will be different amount and shape of the haze and soot particles,and the scattering signals will be attenuated in varying degrees.Therefore it can provide a theoretical basis for improving the transmission characteristics of wireless UV in the complex environment such as the battlefield by analyzing the characteristics of the scattering channel of UV in the haze and soot environment.The parameters of path loss and scattering intensity in different haze and soot particles scattering channels are analyzed and studied on the basis of the UV single and multiple scattering channels.The specific research contents are as follows:At first,scattering channel model in wireless UV haze environment is improved,scattering extinction coefficient of the spherical haze particles and the non spherical haze particles are studied by Mie scattering theory and the T matrix method.The path loss and scattering intensity distribution are simulation analyzed by the single scattering and multiple scattering channel models of wireless UV.The simulation results show that under the same communication distance,the attenuation of UV line-of-sight(LOS)communication is smaller than NLOS communication about lOdB.Finally,the experiments of UV communication system are carried out on haze days and sunny days respectively.The experimental results show that the communication quality of the clear weather is better than haze environment about 8dB when the UV in the LOS communication.The communication quality of the haze environment can be better than the clear environment about 3dB when the UV in NLOS short distance communication.Cluster-Cluster Aggregation(CCA)model and Discrete Dipole Approximation(DDA)method are used to study the path loss and scattering intensity of UV single and multiple scattering channels at different concentrations and original diameters.The simulation results show that,under the same communication distance,the path loss of the scattering channel increases with the increase of soot concentration which in the UV LOS communication,but the change is not obvious,however in NLOS communication,the path loss of the scattering channel decreases with the increase of smoke concentration..In summary,the communication quality becomes worse with the increase of haze and soot concentration under the UV LOS communication,the haze and soot environment can improve the communication quality of to a certain extent under the UV NLOS communication mode.