Study On Radio Wave Propagation Characteristics In The Dusty Plasma

The dusty plasma consists of electrons,ions,neutral particle and dust particle.Owing to the interaction between particles,the dusty plasma has complex electromagnetic(EM)scattering characteristics.According to the difference of particles density,the current research direction is focused on the dusty plasma sheath during the re-entry process of aircraft and the dusty plasma on the lunar surface.The scattering characteristics of the dusty plasma will have a serious impact on the communication signal and the detection signal of lunar surface,and even lead to the interruption of communication link.Therefore,the study of the EM wave propagation parameters in the different dusty plasmas has great engineering application value and scientific research significance.The main work as follows:1)Considering the reflection and attenuation of the communication signal caused by the dusty plasma sheath and high temperature resistant materials in the process of aircraft reentry,the propagation model of terahertz wave in the dusty plasma on ceramic substrate is proposed,and the Scattering Matrix Method(SMM)is used to calculates the transmittion and reflection of the terahertz wave.The results show that increasing the frequency of communication signal can effectively increase the transmittance of the terahertz wave in the dusty plasma sheath.Increasing electron density,dust density,dust radius,collision frequency and incidence Angle will reduce the transmission of EM wave in the dusty plasma.2)In view of the influence of the lunar dusty plasma on the detection signal,the model of the detection signal back and forth in the lunar dusty plasma is established,and the expression of the relationship between the permittivity and reflection coefficient of the lunar soil is deduced.Considering the long propagation path of detection signal in the lunar dusty plasma and the low particle density of the lunar dusty plasma,the attenuation characteristics of the probe signal emitted by the probe radar during the lunar dusty plasma round-trip is studied using the Improved Scattering Matrix Method(ISMM).The results show that the detection signals with higher frequency are more likely to travel back and forth in the lunar dusty plasma and produce weaker interference wave.3)Aiming at the above research works,a software for calculating the scattering characteristics of radio waves in the dusty plasma is designed and developed.Users can independently set some parameters of the dusty plasma and incident wave,while saving simulation the data and results of the simulation.The result of software testing proves that the calculation result of this software is reliable.