The method of moments (MoM) solution combined field integral equation (CFIE) for electromagnetic scattering problems requires calculation singular double surface integrals. When Galerkin's with triangular vector basis functions, Rao-Wilton-Glisson and the CFIE are applied to solve by a dielectric object, both RWG n/spl times/RWG functions (n is normal unit vector) should be considered as testing functions. Robust accurate methods based on singularity extraction technique presented evaluate...

Combined field integral equation (CFIE) is applied for computing electromagnetic scattering by arbitrarily shaped three dimensional dielectric and composite objects. The objectives of this paper are as follows. First, to present a CFIE formulation which can be used in the analysis piecewise metallic objects with junctions. Second, show that properly choosing coupling coefficients equations conditioning discretized matrix essentially improved rapidly converging iterative solutions obtained...

The surface integral equation method is applied for the electromagnetic analysis of general metallic and dielectric structures arbitrary shape. based on EFIE-CFIE-PMCHWT formulation with Galerkins type discretization. numerical implementation divided into three independent steps: First,the electric magnetic field equations are presented discretized individually in each non-metallic subdomain RWG basis testing functions. Next linearly dependent zero unknowns removed from system by enforcing...

In this paper, formulation of the surface integral equations for solving electromagnetic scattering by dielectric and composite metallic objects with iterative methods is studied. Four types formulations are considered: T formulations, N combined field equation formulation, Müller formulation. By studying properties their testing in Galerkin method, “optimal” forms each type derived. Numerical examples demonstrate that developed new lead to clear improvements convergence rates when matrix...

A new stable frequency domain surface integral equation formulation is proposed for the three dimensional electromagnetic scattering of composite metallic and dielectric objects. The developed does not suffer from low breakdown leads to a well balanced system on wide band. Surface charge densities are used as unknowns in addition traditional current densities. balance achieved by using normalized field quantities enforcing continuity fields across boundaries with carefully chosen scaling...

Numerical solution of electromagnetic scattering by homogeneous dielectric objects with the method moments (MoM) and Rao-Wilton-Glisson (RWG) basis functions is discussed. It shown that low-frequency breakdown associated to MoM can be avoided classical Müller formulation without loop-tree or loop-star functions. Two variations formulation, T-Müller N-Müller, are considered. demonstrated only N-Müller Galerkin RWG gives stable solution. Discretization N-Muller leads a well-conditioned matrix...

In this paper a singularity subtraction technique is developed for computing the impedance matrix elements of various electromagnetic surface integral equation formulations with Galerkin method and high-order basis functions. Analytical closed form formulas integrals |r - r'|/sup n/, n/spl ges/-3, singularities times polynomial nodal shape functions arbitrary order on planar triangle are presented.

A stable volume integral equation formulation and its discretization for extremely anisotropic materials is presented. The equations are written in terms of the equivalent currents. currents expanded with piecewise constant basis functions, Galerkin's scheme applied testing equations. Numerical results show that behavior more than behaviors conventional formulations based on fluxes or fields, when scatterer anisotropic. Finally, developed method to analyze a highly material interface which...

The theory of characteristic modes (TCM) is presented for arbitrarily shaped 3-D structures including perfect electric conductors (PECs) and homogeneous penetrable objects. It shown that by properly expressing the weighting operator generalized eigenvalue equation in terms integral operators related to radiated fields, TCM can be formulated directly surface formulation problem. This avoids symmetrization or other modifications equations. eigenvalues are radiated, reactive, dissipated power,...

Abstract A numerical solution of integral equations typically requires calculation integrals with singular kernels. The integration terms can be considered either by purely techniques, e.g. Duffy's method, polar co‐ordinate transformation, or singularity extraction. In the latter method extracted is calculated in closed form and remaining numerically. This has been well established for linear constant shape functions. this paper we extend polynomial functions arbitrary order. We present...

This paper discusses the application of (surface) equivalence principle algorithm (EPA) in solving electromagnetic scattering by multiple metallic and dielectric objects arbitrary shape. The EPA introduced earlier Li, Chew Jiang is generalized for an number scatterers surface integral equation formulation. properties are investigated discussed detail. major benefit that it essentially improves condition system matrix. crucial when matrix solved iteratively, e.g. with Krylov subspace methods....

During the last two-three decades importance of computer simulations based on numerical full-wave solutions Maxwell's has continuously increased in electrical engineering.Software products integral equation methods have an unquestionable frequency domain electromagnetic analysis and design open-region problems.This paper deals with surface volume for finding time-harmonic equations.First a review classical representations formulations is given.Thereafter we briefly overview mathematical...

The volume integral equation method is applied in electromagnetic scattering from arbitrarily shaped three-dimensional inhomogeneous objects. properties of the electric and magnetic field equations (VEFIE VMFIE) are investigated. Numerical experiments show that if Galerkin's with lowest mixed-order basis functions used to discretize accuracy VMFIE can be significantly poorer than VEFIE, particular, for high-contrast objects at high frequencies. essentially improved full first order (linear)...

This article presents results of a numerical effort to determine the dielectric polarizabilities five regular polyhedra: tetrahedron, cube, octahedron, dodecahedron, and icosahedron. The polarizability is calculated by solving surface integral equation, in which unknown potential expanded using third-order basis functions. resulting are accurate order 10/sup -4/. Approximation formulas given for as functions permittivity. Among other results, it found that polyhedron correlates more strongly...

A novel surface integral equation (SIE)-based theory of characteristic modes (TCM) formulation is proposed for homogeneous penetrable bodies. Analytical expressions the eigenvalues are presented and good agreement between numerical analytical results observed both lossless lossy, as well dielectric magnetodielectric objects. The new formulations, without any postprocessing methods, avoid spurious resonances appearing in existing SIE-based TCM formulations. For lossy objects, obtained...

The surface integral equation-based theory of characteristic modes (TCM) is presented for structures including perfect electric conductors (PECs) and lossy dielectric bodies. formulation a combination the classical TCM PEC recently developed one penetrable potential methodology practical antenna design problems demonstrated by studying coupling on plate (antenna ground plane) an adjacent highly block (user's hand). This analysis reveals existence different types having weak or strong...

By studying solutions of various forms the Poggio-Miller-Chang-Harrington-Wu-Tsai (PMCHWT)-based characteristic mode (CM) formulations, we have found that proper choice weighting operator generalized eigenvalue equation is crucial in developing formulations are immune from spurious solutions. Spurious modes Chang-Harrington surface formulation for CMs lossless material bodies shown to be a reverse problem where parameters background and object swapped. These unwanted can avoided by removing...

Duality transformation is applied to the theory of zero backscattering from finite objects. It shown that if object, defined by medium and/or boundary condition, self dual, i.e., invariant in duality transformation, it invisible radar a certain condition for polarizability dyadic valid. This general statement and includes previous theorems as special cases. As novel self-dual objects those with conditions requiring vanishing normal components D B vectors ("DB boundary") or their derivatives...

The surface integral equation method is applied to solve electromagnetic scattering by arbitrarily shaped three-dimensional imperfectly conducting objects modeled with the Leontovitch impedance boundary condition (IBC). Dual basis functions are used remove previously reported difficulties associated solution of combined field for IBC. By expanding magnetic current quasi-curl conforming dual and electric divergence primary (RWG) leads a stable discretization procedure rotation (n ×) operator required

A classical way for exploring the scattering behavior of a small sphere is to approximate Mie coefficients with Taylor series expansion. This ansatz delivered plethora insightful results, mostly spheres supporting electric localized plasmonic resonances. However, many aspects are still uncharted, especially regards magnetic Here, an alternative system proposed based on Pad\'e approximants coefficients. The results reveal existence self-regulating radiative damping mechanism first resonance...

This article presents a design process for hand-immune mobile antenna system. Characteristic modes (CMs) of phone and hand combination are analyzed to find the desired with good radiation properties. The efficient excitation these is implemented by utilizing cluster technique. proposed has small ground clearance only 2 mm can cover 700-960 MHz low band, 1700-2700 middle-high band (MHB) two multiple-input-multiple-output (MIMO) antennas, 3300-3800 high four MIMO antennas. measurement results...

Multipacting can cause breakdown in high power rf components like couplers, windows, etc. This phenomenon starts if certain resonant conditions for electron trajectories are fulfilled and the impacted surface has a secondary yield larger than one. A general cure against multipacting is to avoid conditions. Therefore we investigated dynamics of order find rules these resonances thus suppress by appropriate design. We developed new code which combines standard trajectory calculations with...

Sensitivity analysis is an important part of gradient-based optimization electromagnetic devices. We demonstrate how sensitivity can be incorporated into existing in-house method moments solver with a relatively small amount labor by using technique called automatic differentiation (AD). This approach enables us to obtain (geometrical) sensitivities the discrete solution accuracy up numerical precision. compare assembly time and memory usage modified original solvers. Moreover, we optimize...