Scattering characteristics of non-uniform dusty plasma targets based on Fokker-Planck-Landau collision model

Abstract

Dusty plasma is a multi-particle system of dust particles suspended in plasma, which is generally composed of free electrons, ions, and dust particles. It is widely found in natural space and aerospace equipment, such as the Earth's ionosphere, rocket tail flame, and sheath of the hypersonic vehicle. The dust particles will interact with free electrons and ions in the plasma so that the dust particles are charged. It also significantly changes the characteristics of dusty plasma, showing some phenomena different from ordinary plasma, such as dust acoustic solitary waves, dust void, etc. Electromagnetic (EM) waves will interact with dusty plasma, which results in the attenuation of EM wave signal and the change of phase and other serious effects, and the phenomenon of "blackout" appears. This is very unfavorable to the guidance and control system of the vehicle. The generation of "blackout" is related to the dynamics of dusty plasma and the analysis and research of EM characteristics, so studying the scattering characteristics of dusty plasma is of great significance. First, starting from the Boltzmann equation, the iterative expression of FDTD under the Fokker-Planck-Landau (FPL) collision model of fully ionized non-uniform dusty plasma is derived. The expression of the conductivity of the fully ionized dusty plasma under the FPL collision model is obtained by combining the collision effect and charging effect of the dusty plasma. By using the Z-transform finite-difference time-domain (Z-FDTD) method, the radar cross section (RCS) of the dusty plasma coated metal blunt cone in two dimensions is calculated. The effects of dust particle density, dust particle radius, electron density to dust particle density ratio, dust particle charging frequency, and EM wave incident angle on the scattering characteristics of the mental blunt cone are analyzed. The results show that the Debye shielding effect is weakened and RCS is increased with the increase of the radius of dust particles in the fully ionized non-uniform dusty plasma. In addition, it is affected by the collision effect and charging effect of dusty plasma, which will have a great impact on the RCS of the target. These results provide a theoretical basis for studying the EM waves scattering problem of fully ionized non-uniform dusty plasma and the communication problems in near space.