Electromagnetic modelling of surfaces using method of moments with calculated phase mesh

Abstract

An alternative method of moments (MoM) solution for the radiation and scattering of surfaces is presented. One limit of MoM is the high number of basis functions needed, for the segmentation of electrically large surfaces. In this study, a conventional MoM solution is defined with quadrilateral surface patches and at least eight rooftop basis functions per wavelength. Galerkin testing is applied. This conventional MoM is extended with a new approach for the surface segmentation, called the calculated phase mesh (CPM). Efficient basis functions are chosen, and their positions on the surface are calculated with the incident field. In the theory part, the number of unknowns for scatterers with electrically large dimensions is reduced by 50%, compared with conventional MoM meshes with eight functions per wavelength. The incident field on surfaces is calculated numerically. This allows the application of CPM on scattering bodies with a variety of field sources, for example, both the near and the far field of antennas. The valid frequency range for the meshes is described. Three numerical examples are presented. In one example, the number of basis functions was reduced to 69.3%, compared with conventional MoM. The third example shows the application on three‐dimensional scattering bodies.

Highly squinted SAR imaging simulation of ship‐ocean scene based on EM scattering mechanism

“…A robust scattering model is the foundation of the first problem, which has been studied for decades because of its practical importance [6][7][8][9]. For instance, the generalised forwardbackward (FB) method [10], which is presented by Pino et al, combines the conventional FB method [11] and the method of moment [12,13] to calculate the composite scattering from targets located on rough ocean-like surface. Colak and Newman firstly introduced the multiple sweep method of moments [14], which is an extended version of spatial decomposition technique [15].…”