Derivation of Analytic Formulas and Numerical Verification of Weakly Singular Integrals for Near-Field Correction in Surface Integral Equations |
Jae-Won Rim, Il-Suek Koh |
Department of Electronic Engineering, Inha University |
Correspondence:
Il-Suek Koh,Email: ikoh@inha.ac.kr |
|
|
|
Abstract |
An accurate and efficient evaluation for hypersingular integrals (HIs), strongly singular integrals (SSIs), and weakly singular integrals (WSIs) plays an essential role in the numerical solutions of 3D electromagnetic scattering problems. We derive analytic formulas for WSIs based on Stokes' theorem, which can be expressed in elementary functions. Several numerical examples are presented to validate these analytic formulas. Then, to show the feasibility of the proposed formulations for numerical methods, these formulations are used with the existing analytical expressions of HIs and SSIs to correct the near-field interaction in an iterative physical optics (IPO) scheme. Using IPO, the scattering caused by a dihedral reflector is analyzed and compared with the results of the method of moments and measurement data. |
Key words:
Iterative Physical Optics, Near-Field Correction, Singularity Subtraction, Weakly Singular Integrals |
|