Computational electromagnetics

About: Computational electromagnetics is a research topic. Over the lifetime, 6412 publications have been published within this topic receiving 113727 citations. The topic is also known as: Electromagnetic field analysis.

Systematic and efficient root finder for computing the modal spectrum of planar layered waveguides

Abstract: An efficient and systematic strategy to find the propagation constants of real, complex, and leaky modes of covered and uncovered planar multilayered isotropic/uniaxial waveguides is presented. This strategy first builds up a pole-free characteristic function and then makes use of a root-searching scheme based on an integral nature method to search for its zeros. For uncovered waveguides, the branch points of the characteristic function can be removed by introducing the upper half-space vertical wavenumber as the working variable. Examples of the efficiency, reliability, and robustness of the presented technique are given for both covered and uncovered waveguides, which sets up this technique as a very convenient CAD tool. The method is also applied to study a new and interesting problem: the evolution of the modes of a grounded dielectric waveguide when increasing the permittivity of the upper semi-infinite medium. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 14, 73–83, 2004

A pseudospectral frequency-domain (PSFD) method for computational electromagnetics

Abstract: This letter describes a new frequency-domain method for Maxwell's equations based on the multidomain pseudospectral method. The computational domain is first divided into nonoverlapping subdomains. Using the Chebyshev polynomials to represent the unknown field components in each subdomain, the spatial derivatives are calculated with a spectral accuracy at the Chebyshev collocation points. The physical boundary conditions at the subdomain interfaces are enforced to ensure the global accuracy. Numerical results demonstrate that the pseudospectral frequency-domain (PSFD) method has a spectral accuracy, and thus is an attractive method for large-scale problems. With only about five cells per wavelength, the results have an error less than 1% in our typical examples.

Large-Scale, Full-Wave-Based Emulation of Step-Frequency Forward-Looking Radar Imaging in Rough Terrain Environments

Abstract: Large-scale, full-wave modeling of multistatic target imaging in a rough ground environment is described. The emulation methodology employs a parallelized three-dimensional “near-field” finite-difference time-domain algorithm in characterizing the electromagnetic scattering from the ground surface and buried and on-surface targets in the form of landmines and unexploded ordnances; subsequent focusing of the scattered fields into an image is obtained by exploiting the time-reversal technique applied over a spectral band consistent with one used by a step-frequency system under development. Imaging performance is investigated with numerical experiments for both single- and multi-aperture sensing geometries. The emphasis of this study is on examining the responses of discrete ground targets in the presence of distributed variable ground clutter as relevant to performance prediction for ultra-wideband forward-looking radar applications.

Numerical solution of 2D and 3D induction heating problems with non-linear materml properties taken into account

Abstract: A numerical calculation model for the solution of 2D and 3D induction heating problems, which takes the nonlinearities of both the electromagnetic and thermal material properties into account, is described. The solution of a 2D-coupled field problem is found by traditional FEM. In a 3D analysis nonlinear surface impedances are utilized in the magnetic field problem and the power transfer to the workpiece is modeled using heat fluxes. The performance of the model was verified by comparing the calculated temperature profiles with the measurements.