Scattering from 3-D cavities with a plug and play numerical scheme combining IE, PDE, and modal techniques

Abstract

In this paper, we present a multidomain and multimethod coupling scheme called FACTOPO, based on generalized scattering matrix computations on three-dimensional (3-D) subdomains. The global target is split in subdomains ( ) =1 , separated by fictitious surfaces (0 ) =1 . We use a modal representation of the tangent fields on the interfaces. In each domain, the generalized Scattering matrix is computed with different methods such as the 3-D finite-element method (FEM) or the electric field integral equation (EFIE). This coupling scheme leads to an important reduction in computational resources, especially for cavities with one dimension much larger than the other two. The advantages of this formulation for parametric studies will be illustrated by two cases: computing the RCS of an air-intake terminated with a flat PEC or a fan (CHANNEL) and of an antenna structure coupled to an electronic feed with a varying parameter (DENEB). Numerical as well as experimental results are presented.

A Hybrid Finite Element and Integral Equation Domain Decomposition Method for the Solution of the 3-D Scattering Problem

“…The results that are presented in this section have been obtained on a sphere, a conesphere, a "stopper," and the air intake defined in [8] ("channel"). The first three objects are inhomogeneous BORs.…”

“…10). We refer to [8] for additional information on the geometry (note that the definition of the x, y, z axes differs from the one in [8]). The object is perfectly conducting (Z = 0).…”

Simplifying the propagation environment representation for LMS channel modelling

“…With this rigorous approach, sub-wavelength elements can be taken into consideration. In the following, we used the EM code ELSEM3D [13,14] from ONERA to compute all simulations discussed next. It is based on the Electric Field Integral Equation solved with MoM techniques in the frequency domain.…”

Stability for the Electromagnetic Scattering from Large Cavities

“…In the context of design, an optimization procedure was used to enhance or reduce the RCS in [7,8]. A great deal of mathematical and computational methods have been studied for the scattering by cavities, including variational and finite element methods ( [2,4]), integral equation methods ( [1,3,5,25]), time-domain methods ( [21][22][23][24]), and hybrid methods ( [6,10,15,16,19,20]). The goal of this work is to establish the stability estimates of cavity problems with explicit dependence on the high wavenumber.…”