Acceleration of MLFMA Simulations Using Trimmed Tree Structures

2021-01-01
Karaosmanoglu, Bariscan
Ergül, Özgür Salih
We present a novel approach to accelerate the electromagnetic simulations by the multilevel fast multipole algorithm (MLFMA). The strategy is based on a progressive elimination of the electromagnetic interactions, resulting in trimmed tree structures, during iterative solutions. To perform such eliminations systematically, artificial neural network (ANN) models are constructed and trained to estimate the errors in the updated surface current coefficients. These column eliminations are supported by straightforward row eliminations, leading to increasingly sparse tree structures and matrix equations as iterations continue. We show that the proposed implementation, namely, trimmed MLFMA (T-MLFMA), leads to significantly accelerated electromagnetic simulations of the large-scale objects, while the accuracy is still much better than the high-frequency techniques. T-MLFMA can be seen as an exemplar of the implementations, where machine learning is successfully integrated into an electromagnetic solver for enhanced simulations.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION

Suggestions

Electromagnetic interaction complexity reduction using deep learnin
Karaosmanoğlu, Barışcan; Ergül, Özgür Salih; Department of Electrical and Electronics Engineering (2019)
In this thesis, we present a novel approach to accelerate electromagnetic simulations by the multilevel fast multipole algorithm (MLFMA). The strategy is based on a progressive elimination of electromagnetic interactions, resulting in trimmed tree structures, during iterative solutions. To systematically perform such eliminations, artificial neural network (ANN) models are constructed and trained to estimate errors in updated surface current coefficients. These column eliminations are supported by straightf...
Efficient and Accurate Electromagnetic Optimizations Based on Approximate Forms of the Multilevel Fast Multipole Algorithm
Onol, Can; Karaosmanoglu, Bariscan; Ergül, Özgür Salih (2016-01-01)
We present electromagnetic optimizations by heuristic algorithms supported by approximate forms of the multilevel fast multipole algorithm (MLFMA). Optimizations of complex structures, such as antennas, are performed by considering each trial as an electromagnetic problem that can be analyzed via MLFMA and its approximate forms. A dynamic accuracy control is utilized in order to increase the efficiency of optimizations. Specifically, in the proposed scheme, the accuracy is used as a parameter of the optimiz...
Fast and accurate analysis of optical metamaterials using surface integral equations and the parallel multilevel fast multipole algorithm
Ergül, Özgür Salih (2013-09-13)
We present fast and accurate simulations of optical metamaterials using surface integral equations and the multilevel fast multipole algorithm (MLFMA). Problems are formulated with the electric and magnetic current combined-field integral equation and solved iteratively with MLFMA, which is parallelized using the hierarchical strategy on distributed-memory architectures. Realistic metamaterials involving dielectric, perfectly conducting, and plasmonic regions of finite extents are solved rigorously with the...
Analysis of double-negative materials with surface integral equations and the multilevel fast multipole algorithm
Ergül, Özgür Salih (2011-08-13)
We present a fast and accurate analysis of double-negative materials (DNMs) with surface integral equations and the multilevel fast multipole algorithm (MLFMA). DNMs are commonly used as simplified models of metamaterials at resonance frequencies and are suitable to be formulated with surface integral equations. However, realistic metamaterials and their models are usually very large with respect to wavelength and their accurate solutions require fast algorithms, such as MLFMA. We consider iterative solutio...
Extension of forward-backward method with DFT-based acceleration algorithm for the efficient analysis of large periodic arrays with arbitrary boundaries
Aydın Çivi, Hatice Özlem; Chou, HT (Wiley, 2005-11-05)
An extension of the discrete Fourier transform (DFT)-based forward-backward algorithm is developed using the virtual-element approach to provide a fast and accurate analysis of electromagnetic radiation/scattering front electrically large, planar, periodic, finite (phased) arrays with arbitrary boundaries. Both the computational complexity and storage requirements of this approach are O(N-tot) (N-tot is the total number of unknowns). The numerical results for both printed and freestanding dipole array's wit...
Citation Formats
B. Karaosmanoglu and Ö. S. Ergül, “Acceleration of MLFMA Simulations Using Trimmed Tree Structures,” IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, pp. 356–365, 2021, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/90035.