Effective preconditioners for large integral-equation problems

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2007-11-16

Author

Malas, T.
Ergül, Özgür Salih
Gürel, L.

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We consider effective preconditioning schemes for the iterative solution of integral-equation methods. For parallel implementations, the sparse approximate inverse or the iterative solution of the near-field system enables fast convergence up to certain problem sizes. However, for very large problems, the near-field matrix itself becomes too crude approximation to the dense system matrix and preconditioners generated from the near-field interactions cannot be effective. Therefore, we propose an approximation strategy to the multilevel fast multipole algorithm (MLFMA) to be used as a preconditioner. Our numerical experiments reveal that this scheme significantly outperforms other preconditioners. With the combined effort of effective preconditioners and an efficiently parallelized MLFMA, we are able to solve targets with tens of millions of unknowns in a few hours.

Subject Keywords

Preconditioning, Electromagnetic scattering, Integral equation methods, Multilevel fast multipole algorithm, Large-scale problems

URI

https://hdl.handle.net/11511/48879

DOI

https://doi.org/10.1049/ic.2007.1166

Collections

Department of Electrical and Electronics Engineering, Conference / Seminar

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Citation Formats

T. Malas, Ö. S. Ergül, and L. Gürel, “Effective preconditioners for large integral-equation problems,” 2007, vol. 2007, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/48879.