High-Precision Integration Using Singularity Cancelation in Method of Moments

We present coordinate transformations that cancel logR, 1/R, and 1/$R^{2}$ singularities encountered in electromagnetic analysis of bodies of revolution and two-dimensional structures. They are intended for entire-domain high-order method of moments analysis of both flat and curvilinear two-dimensional strips made of a perfect electric conductor, and of bodies of revolution with metallic and dielectric domains. After the transformations, the integrals with these singularities are calculated up to 14 significant digits using the Gauss-Legendre procedure. Owing to the high-precision integration, the entire-domain analysis of two-dimensional structures is successfully performed on a strip with width up to 4,000 wavelengths. High-precision integration for body of revolution analysis enabled the full-wave numerical model of the custom-made coaxial chamber for dielectric measurement. This increased the upper frequency limit for the extraction of dielectric parameters from 1 GHz up to 3 GHz.