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

Download

index.pdf

Date

2008-03-01

Author

Ergül, Özgür Salih

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

201
views

0
downloads

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

Suggestions

OpenMETU
Core

Use of Asymptotic Waveform Evaluation Technique in the Analysis of Multilayer Structures With Doubly Periodic Dielectric Gratings Gudu, Tamer; Alatan, Lale (Institute of Electrical and Electronics Engineers (IEEE), 2009-09-01) The reflection and dispersion characteristics of multilayer structures that involve periodically implanted material blocks are obtained by using the MoM solution of the volume integral equation. The asymptotic waveform evaluation (AWE) technique is utilized to obtain a Pade approximation of the solution in terms of a parameter such as frequency or incident angle. The use of AWE technique enables a fast sweep with respect to the approximation parameter. Moreover, a robust method for extracting the dispersion...
Efficient parallelization of the multilevel fast multipole algorithm for the solution of large-scale scattering problems Ergül, Özgür Salih (Institute of Electrical and Electronics Engineers (IEEE), 2008-08-01) We present fast and accurate solutions of large-scale scattering problems involving three-dimensional closed conductors with arbitrary shapes using the multilevel fast multipole algorithm (MLFMA). With an efficient parallelization of MLFMA, scattering problems that are discretized with tens of millions of unknowns are easily solved on a cluster of computers. We extensively investigate the parallelization of MLFMA, identify the bottlenecks, and provide remedial procedures to improve the efficiency of the imp...
Efficient solution of the electric-field integral equation using the iterative LSQR algorithm Ergül, Özgür Salih (Institute of Electrical and Electronics Engineers (IEEE), 2008-01-01) In this letter, we consider iterative solutions of the three-dimensional electromagnetic scattering problems formulated by surface integral equations. We show that solutions of the electric-field integral equation (EFIE) can be improved by employing an iterative least-squares QR (LSQR) algorithm. Compared to many other Krylov subspace methods, LSQR provides faster convergence and it becomes an alternative choice to the time-efficient no-restart generalized minimal residual (GMRES) algorithm that requires la...
Implementation of the Equivalence Principle Algorithm for Potential Integral Equations Farshkaran, Ali; Ergül, Özgür Salih (Institute of Electrical and Electronics Engineers (IEEE), 2019-05-01) A novel implementation of the equivalence principle algorithm (EPA) employing potential integral equations (PIEs) is presented. EPA is generalized to be compatible with PIEs that are used to formulate inner problems inside equivalence surfaces. Based on the stability of PIEs, the resulting EPA-PIE implementation is suitable for low-frequency problems involving dense discretizations with respect to wavelength. Along with the formulation and a clear demonstration of the EPA-PIE mechanism, high accuracy, stabi...
Fast and accurate solutions of extremely large integral-equation problems discretised with tens of millions of unknowns Gurel, L.; Ergül, Özgür Salih (Institution of Engineering and Technology (IET), 2007-04-26) The solution of extremely large scattering problems that are formulated by integral equations and discretised with tens of millions of unknowns is reported. Accurate and efficient solutions are performed by employing a parallel implementation of the multilevel fast multipole algorithm. The effectiveness of the implementation is demonstrated on a sphere problem containing more than 33 million unknowns, which is the largest integral-equation problem ever solved to our knowledge.

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.