Fast and accurate solutions of scattering problems involving dielectric objects with moderate and low contrasts

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2007-08-31

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Ergül, Özgür Salih

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We consider the solution of electromagnetic scattering problems involving relatively large dielectric objects with moderate and low contrasts. Three-dimensional objects are discretized with Rao-Wilton-Glisson functions and the scattering problems are formulated with surface integral equations. The resulting dense matrix equations are solved iteratively by employing the multilevel fast multipole algorithm. We compare the accuracy and efficiency of the results obtained by employing various integral equations for the formulation of the problem. If the problem size is large, we show that a combined formulation, namely, electric-magnetic current combined-field integral equation, provides faster iterative convergence compared to other formulations, when it is accelerated with an efficient block preconditioner. For low-contrast problems, we introduce various stabilization procedures in order to avoid the numerical breakdown encountered in the conventional surface formulations.

Subject Keywords

Dielectrics, Integral equations, Boundary conditions, Electromagnetic scattering, MLFMA, Testing, Acceleration, Magnetic fields, Computational electromagnetics, Convergence

URI

https://hdl.handle.net/11511/47372

DOI

https://doi.org/10.1109/cem.2007.4387652

Collections

Department of Electrical and Electronics Engineering, Conference / Seminar

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Citation Formats

Ö. S. Ergül, “Fast and accurate solutions of scattering problems involving dielectric objects with moderate and low contrasts,” 2007, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47372.