Stabilization of integral-equation formulations for the accurate solution of scattering problems involving low-contrast dielectric objects

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2008-03-01

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Ergül, Özgür Salih

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The solution of scattering problems involving low-contrast dielectric objects with three-dimensional arbitrary shapes is considered. Using the traditional forms of the surface integral equations, scattered fields cannot be calculated accurately if the contrast of the object is low. Therefore, we consider the stabilization of the formulations by extracting the nonradiating parts of the equivalent currents. We also investigate various types of stable formulations and show that accuracy can be improved systematically by eliminating the identity terms from the integral-equation kernels. Traditional and stable formulations are compared, not only for small scatterers but also for relatively large problems solved by employing the multilevel fast multipole algorithm. Stable and accurate solutions of dielectric contrasts as low as 10(-4) are demonstrated on problems involving more than 250000 unknowns.

Subject Keywords

Electrical and Electronic Engineering

URI

https://hdl.handle.net/11511/48031

Journal

IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION

DOI

https://doi.org/10.1109/tap.2008.916971

Collections

Department of Electrical and Electronics Engineering, Article

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Citation Formats

Ö. S. Ergül, “Stabilization of integral-equation formulations for the accurate solution of scattering problems involving low-contrast dielectric objects,” IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, pp. 799–805, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/48031.