A hybrid method for the solution of scattering from inhomogeneous dielectric cylinders of arbitrary shape

Abstract

A hybrid moment methdedge-element method (MMlEEM) is presented. The formulation is quite general; however, the method is applied to two-dimensional scattering problems. Such a hybrid formulation unites the advantages of finite and integral-equation methods and is able to handle unbounded problems in which complex inhomogeneities are present. The edge-element method is easily coupled to the moment method, and it doesn't introduce spurious modes. The equivalence principle is used to divide the original problem into two separate problems: an unbounded homogeneous one in which the moment method is used and a bounded inhomogeneous one in which the edge-element method is used. Several examples involving two-dimensional scattering with TE and TM plane wave excitation are presented. The RCS is computed and compared to results obtained by other numerical techniques.

Critical frequencies for solving electromagnetic scattering problems by the moment/finite-element method

“…The modal expansion cavity model [4] for the analysis of an aperture-coupled microstrip antenna is more complicated and time consuming than a simple cavity model [5] for such a structure, although the first gives a more accurate impedance value than the second. The analysis of an aperture-coupled microstrip antenna using a cavity model has been reported [5] for the fundamental mode only.…”

Crack Detection Using a Hybrid Finite Difference Frequency Domain and Particle Swarm Optimization Techniques

“…Good agreement is obtained. Figure 5 compares the bistatic radar cross section patteren of a four layered dielectric object using the FDFD and that obtained by Jankovic et al [15]. The object dimensions are a 1 = 0.15λ, a 2 = 0.2λ, a 3 = 0.25λ, a 4 = 0.3λ, ε r1 = 8, ε r2 = 6, ε r3 = 4, and ε r4 = 2 for TM z plane wave.…”

Single integral evaluation for wave scattering by a layered dielectric cylinder

“…The key elements of the formulation are the linear relationships between the unknown single source currents Ji and J i + on successive interfaces, and the exclusive operators which represent the fields on each surface Si in terms of only a single equivalent current J j on that surface. The method is highly efficient as compared to the classical coupled, double source surface integral equations, as well as to volume integral equation methods [2] and to hybrid momenvfinite volume techniques [7].…”

“…2(a)), we note that it contains no internal scattering body and, consequently, no local scattered field. Thus, the actual field E in V, is comprised solely of the local incident field E r " , which is generated by the electric surface current J , on S, , (7) such that where the left-hand side superscripts and subscripts p and q indicate the field surface and the source surface, respectively, the right-hand side subscript provides the index of the mate-…”