Scattering And Transmission Characteristics Of The Terahertz Wave In The Plasma

Plasma has special electromagnetic properties and will severely attenuate incident electromagnetic waves.So,if the plasma covers the surface of the aircraft,communication with the outside world will be interrupted,and it is difficult for microwave radar to track and find such targets.The frequency of terahertz waves is higher than that of microwaves,which has stronger penetration and directivity,and can penetrate high-density plasma.Therefore,studying the propagation characteristics of terahertz waves in plasma is very important for improving the safety of spacecraft and advancing the advancement of national defense technology.The research in this article is mainly divided into the following parts:First,the numerical calculation method was used to simulate the attenuation and scattering of the incident terahertz wave energy by the planar and cylindrical non-uniform nonmagnetized plasma.And study the effects of different plasma distribution models,electron density,collision frequency and plasma layer thickness on the transmission of terahertz wave.Then,based on the measurement principle of the terhertz time-domain spectroscopic system,the process of inversion of multiple measurement data by the genetic algorithm to realize plasma diagnosis was simulated.Finally,this thesis introduces and compares two methods for calculating the scattering field of the electromagnetic wave incident on the cylinder array: ISP and GMM.The transmission field of the plasma discharge tube array with different parameters and arrangements of microwave incidence was calculated by using GMM.The research results show that in order to reduce the transmission energy of electromagnetic waves,in addition to changing the plasma parameters of the discharge tube,it can also be achieved by increasing the number of arrangement layers and adopting mosaic arrangement.