Development of hypersonic aircraft demands relativistic electromagnetic scattering modeling of a high-speed moving dielectric coated object, which is applied to the recognition and tracking of moving stealth object. However, far-zone polarized scatterings from a moving 3D dielectric coated object have not been investigated so far. This paper addresses this problem by combining the finite-difference time-domain method with Lorentz transformation (Lorentz-FDTD). Through Lorentz transformation and the principle of phase invariance, the frequency, propagation direction, magnitude of the incident plane wave and the size of the moving object in the laboratory frame, which is stationary with respect to the free space, are transformed to those in the rest frame that moves with the moving object. The scattered field near the object is solved by the FDTD method with full permittivity and conductivity tensors in the rest frame, then farzone polarized scattered field is obtained by the implementation of near-to-far field transformation. Through Lorentz transformation for coordinates, the polarized Radar Cross Sections (RCSs) of moving plasma coated objects are solved. Especially, the scattering characteristics of radial radar cross sections of moving objects are discussed. Several numerical experiments are carried out, the efficiency and the accuracy of the proposed method are validated. INDEX TERMS Finite-difference time domain (FDTD), Lorentz-transformation, high-speed, anisotropic media.

Accurate modeling of relativistic electromagnetic scattering characteristics from high-speed motion of plasma coated objects is crucial for the development of hypersonic aircraft and their applications in the identification and surveillance of moving stealth targets. Nevertheless, a solution for bistatic polarized radar cross sections (RCSs) from a 3-D object with plasma coated layer in motion has yet to be obtained. This manuscript proposes a solution to this problem by employing a combination of the auxiliary differential equation (ADE) method with Lorentz finite-difference time-domain (FDTD) method. Utilizing the Lorentz transformation, this paper presents the transformation of parameters of the incident plane wave and dimensions of the object between the laboratory system that remains static and the rest system that remains stationary relative to the object in high-speed motion. The near-zone electromagnetic fields near the object are computed using the ADE method in the rest system, after which the near-field to far-field (NF-FF) transformation is employed to obtain the far-zone polarized scattered field. By applying Lorentz transformation to the coordinates, this paper presents a solution for the polarized scattering from moving plasma coated objects. Especially, radial components of the polarized scatterings are analyzed. The proposed method is validated through several numerical experiments, demonstrating its efficiency and accuracy.