Reliable approach for bistatic scattering of three-dimensional targets from underlying rough surface based on parabolic equation

Abstract

A parabolic equation (PE) based method for analyzing composite scattering under an electromagnetic wave incidence at low grazing angle, which composes of three-dimensional (3-D) electrically large targets and rough surface, is presented and discussed. A superior high-order PE version is used to improve the accuracy at wider paraxial angles, and along with the alternating direction implicit (ADI) differential technique, the computational efficiency is further improved. The formula of bistatic normalized radar cross section is derived by definition and near-far field transformation. Numerical examples are given to show the validity and accuracy of the proposed approach, in which the results are compared with those of Kirchhoff approximation (KA) and moment of method (MoM). Furthermore, the bistatic scattering properties of composite model in which the 3-D PEC targets on or above the two-dimensional Gaussian rough surfaces under the tapered wave incidence are analyzed.

Shared aperture metasurface antenna for electromagnetic vortices generation with different topological charges*

“…Theoretically, owing to the compensation for spatial parabolic phase gradients, the reflective vortex beams will propagate along the normal direction rather than oblique direction. [22] The designing process of metasurface reflector is depicted in Fig. 4(c).…”

“…With the development of artificial materials, metasurface has become an alternative tool to design OAM generator due to the advantages of negligible thickness and huge manipulation flexibility. [1,2,5,[11][12][13][14][15][16][17][18][19][20][21][22] Unfortunately, the mechanism of generating OAM by the aforementioned strategies introduces a twist phase profile. Therefore, it is hard to achieve vortex beams with versatile topological charges in a shared aperture.…”

A hybrid method of solving near-zone composite eletromagnetic scattering from targets and underlying rough surface*

“…Electromagnetic (EM) scattering from targets in extra-low-altitude and environments could be abstracted into scattering problems of radar targets above rough surface. The conventional farfield scattering from rough surface and targets has been widely investigated in the past decades, [1][2][3][4] but research on near-field scattering from targets and surface has rarely been reported yet, which is really a hot topic and challenging issue. The nearfield scattering from targets in free space is computed by using accurate multilevel fast multi-pole method (MLFMM), and application advices on near-field characteristics were given in Ref.…”