Improving the accuracy of the surface integral equations for low-contrast dielectric scatterers

Solutions of scattering problems involving low-contrast dielectric objects are considered by employing surface integral equations. A stabilization procedure based on extracting the non-radiating part of the induced currents is applied so that the remaining radiating currents can be modelled appropriately and the scattered fields from the low-contrast objects can be calculated with improved accuracy. Stabilization is applied to both tangential (T) and normal (N) formulations in order to use the benefits of different formulations.


Improving the accuracy of the MFIE with the choice of basis functions
Ergül, Özgür Salih (2004-06-26)
In the method-of-moments (MOM) and the fast-multipole-method (FMM) solutions of the electromagnetic scattering problems modeled by arbitrary planar triangulations, the magnetic-field integral equation (MFIE) can be observed to give less accurate results compared to the electric-field integral equation (EFIE), if the current is expanded with the Rao-Wilton-Glisson (RWG) basis functions. The inaccuracy is more evident for problem geometries with sharp edges or tips. This paper shows that the accuracy of the M...
Combined-field solution of composite geometries involving open and closed conducting surfaces
Ergül, Özgür Salih (2005-04-07)
Combined-field integral equation (CFIE) is modified and generalized to formulate the electromagnetic problems of composite geometries involving both open and closed conducting surfaces. These problems are customarily formulated with the electric-field integral equation (EFIE) due to the presence of the open surfaces. With the new definition and application of the CFIE, iterative solutions of these problems are now achieved with significantly improved efficiency compared to the EFIE solution, without sacrifi...
Comparison of Integral-Equation Formulations for the Fast and Accurate Solution of Scattering Problems Involving Dielectric Objects with the Multilevel Fast Multipole Algorithm
Ergül, Özgür Salih (2009-01-01)
We consider fast and accurate solutions of scattering problems involving increasingly large dielectric objects formulated by surface integral equations. We compare various formulations when the objects are discretized with Rao-Wilton-Glisson functions, and the resulting matrix equations are solved iteratively by employing the multilevel fast multipole algorithm (MLFMA). For large problems, we show that a combined-field formulation, namely, the electric and magnetic current combined-field integral equation (...
Rigorous Solutions of Electromagnetic Problems Involving Hundreds of Millions of Unknowns
Ergül, Özgür Salih (2011-02-01)
Accurate simulations of real-life electromagnetic problems with integral equations require the solution of dense matrix equations involving millions of unknowns. Solutions of these extremely large problems cannot be easily achieved, even when using the most powerful computers with state-of-the-art technology. Hence, many electromagnetic problems in the literature have been solved by resorting to various approximation techniques, without controllable error. In this paper, we present full-wave solutions of sc...
On the Accuracy and Efficiency of Surface Formulations in Fast Analysis of Plasmonic Structures via MLFMA
Karaosmanoglu, B.; Yılmaz, Ayşen; Ergül, Özgür Salih (2016-08-11)
We consider the accuracy and efficiency of surface integral equations, when they are used to formulate electromagnetic problems involving plasmonic objects at optical frequencies. Investigations on the iterative solutions of scattering problems with the multilevel fast multipole algorithm show that the conventional formulations, especially the state-of-the-art integral equations, can significantly be inaccurate, in contrast to their performances for ordinary dielectrics. The varying performances of the form...
Citation Formats
Ö. S. Ergül, “Improving the accuracy of the surface integral equations for low-contrast dielectric scatterers,” 2007, Accessed: 00, 2020. [Online]. Available: