Open problems in CEM

Date

2013-09-09

Author

Ergül, Özgür Salih

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This work provides an overview of a parallel, high-order, error-controllable framework for solving large-scale scattering problems in electromagnetics, as well as open problems pertinent to such solutions. The method is based on the higherorder locally corrected Nystrom (LCN) discretization of the combined-field integral equation (CFIE), accelerated with the error-controlled Multi-Level Fast Multipole Algorithm (MLFMA). Mechanisms for controlling the accuracy of calculations are discussed, including geometric representation, stages of the locally corrected Nystrom method, and the MLFMA. Also presented are the key attributes of parallelization for the developed numerical framework. Numerical results validate the proposed numerical scheme by demonstrating higher-order error convergence for smooth scatterers. For the problem of scattering from a sphere, the developed numerical solution is shown to have the ability to produce a solution with a maximum relative error of the order 10-9. Open-ended problems, such as treatment of general scatterers with geometric singularities, construction of well-conditioned operators, and current challenges in development of fast iterative and direct algorithms, are also discussed.

Subject Keywords

Integral Equations, High-Order Solution, MLFMA, Scattering

URI

https://hdl.handle.net/11511/40133

Journal

IEEE Antennas and Propagation Magazine

DOI

https://doi.org/10.1109/map.2013.6586691

Collections

Department of Electrical and Electronics Engineering, Article

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Citation Formats

Ö. S. Ergül, “Open problems in CEM,” IEEE Antennas and Propagation Magazine, pp. 294–294, 2013, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40133.