Implementation of Higher-Order Two-Dimensional Singular Elements in FEM codes and Numerical Results problems

This paper presents strategies and schemes to implement higher-order two dimensional singular elements in Finite Elements codes. Accurate numerical results are presented and the efficiency of the schemes is discusse

Skew Incidence on Concave Wedge With Anisotropic Surface Impedance

The diffraction of a plane wave at skew incidence by an arbitrary-angled concave wedge with anisotropic impedance faces is studied. Concave wedges are of interest in wireless propagation models, in particular on modeling buildings and reflectors. The solution is obtained via the generalized Wiener-Hopf technique for arbitrary impedance wedges using a numerical-analytical approach. The numerical results show the spectral properties of the fields, GTD/UTD diffraction coefficients, and total field

Machine Precision Evaluation of Singular and Nearly Singular Potential Integrals by Use of Gauss Quadrature Formulas for Rational Functions

A new technique for machine precision evaluation of singular and nearly singular potential integrals with 1/R singularities is presented. The numerical quadrature scheme is based on a new rational expression for the integrands, obtained by a cancellation procedure. In particular, by using library routines for Gauss quadrature of rational functions readily available in the literature, this new expression permits the exact numerical integration of singular static potentials associated with polynomial source distributions. The rules to achieve the desired numerical accuracy for singular and nearly singular static and dynamic potential integrals are presented and discussed, and several numerical examples are provide