Solutions of new potential integral equations using approximate stable diagonalization of the Green's function

Date

2017-09-15

Author

Gur, U.M.
Karaosmanoglu, B.
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

59
views

0
downloads

We present efficient and accurate solutions of scattering problems involving dense discretizations with respect to wavelength. Recently developed potential integral equations (PIEs) for stable solutions of low-frequency problems are used to formulate such challenging problems, where the electric current density and magnetic vector potential are defined as unknowns. For solving problems discretized with large numbers of unknowns, we further use an approximate diagonalization of the Green's function within the multilevel fast multipole algorithm (MLFMA). The capability of the implementation based on PIEs and MLFMA is demonstrated on canonical problems, whose solutions are difficult via the conventional formulations and/or standard acceleration methods.

Subject Keywords

Engineering, Electrical & Electronic

URI

https://hdl.handle.net/11511/39471

DOI

https://doi.org/10.1109/iceaa.2017.8065676

Conference Name

19th International Conference on Electromagnetics in Advanced Applications (ICEAA)

Collections

Department of Electrical and Electronics Engineering, Conference / Seminar

Suggestions

OpenMETU
Core

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...
Approximate Stable Diagonalization of the Green's Function for Low Frequencies Ergül, Özgür Salih (Institute of Electrical and Electronics Engineers (IEEE), 2014-01-01) We present an approximate diagonalization of the Green's function that is stable at arbitrarily short distances with respect to wavelength. The diagonalization is based on scaled spherical functions and plane waves, where a scaling factor is used to stabilize special functions with small arguments. Optimization of the scaling factor leads to accurate diagonalizations, which can be used to implement the multilevel fast multipole algorithm for low-frequency problems.
Contamination of the Accuracy of the Combined-Field Integral Equation With the Discretization Error of the Magnetic-Field Integral Equation Gurel, Levent; Ergül, Özgür Salih (Institute of Electrical and Electronics Engineers (IEEE), 2009-09-01) We investigate the accuracy of the combined-field integral equation (CFIE) discretized with the Rao-Wilton-Glisson (RWG) basis functions for the solution of scattering and radiation problems involving three-dimensional conducting objects. Such a low-order discretization with the RWG functions renders the two components of CFIE, i.e., the electric-field integral equation (EFIE) and the magnetic-field integral equation (MFIE), incompatible, mainly because of the excessive discretization error of MFIE. Solutio...
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.
A New Approach to Investigation of the Relationship of VLF Signals by Using Longitudinal Analysis Models Guzel, E.; Yaşar, M.; Kılıç, M. B.; Canyılmaz, M. (Hindawi Limited, 2013) Longitudinal analysis models are applied to analyze very low frequency (VLF) electromagnetic waves signals. They are useful in realization of nuance of relationship between parameters of concern which change over time. VLF data are so important for the communication and determining the disturbances in the lower ionosphere. In this study, we used a four-day VLF signal data which come from transmitter stations located at two different countries to Elazi. g receiver system. A very important feature of this dat...

Citation Formats

U. M. Gur, B. Karaosmanoglu, and Ö. S. Ergül, “Solutions of new potential integral equations using approximate stable diagonalization of the Green’s function,” presented at the 19th International Conference on Electromagnetics in Advanced Applications (ICEAA), Verona, ITALY, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39471.