Enhancing the accuracy of the interpolations and anterpolations in MLFMA

We present an efficient technique to reduce the interpolation and anterpolation (transpose interpolation) errors in the aggregation and disaggregation processes of the multilevel fast multipole algorithm (MLFMA), which is based on the sampling of the radiated and incoming fields over all possible solid angles, i.e., all directions on the sphere. The fields sampled on the sphere are subject to various operations, such as interpolation, aggregation, translation, disaggregation, anterpolation, and integration. We identify the areas on the sphere, where the highest levels of interpolation errors are encountered. The error is reduced by employing additional samples on such parts of the sphere. Since the interpolation error is propagated and amplified by every level of aggregation, this technique is particulary useful for large problems. The additional costs in the memory and processing time are negligible, and the technique can easily be adapted into the existing implementations of MLFMA.


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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...
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A method for the construction of complementary sets of sequences using polyphase representation of orthogonal filterbanks is presented. It is shown that the case of two-channel filterbanks unifies individually derived length extension formulas for complementary sequences into a common framework and the general M-channel case produces novel formulas for the extension of complementary sets of sequences. The presented technique can also be used to generate polyphase and multilevel sequences.
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Aksun, MI; Dural Ünver, Mevlüde Gülbin (Institute of Electrical and Electronics Engineers (IEEE), 2005-11-01)
The closed-form Green's functions (CFGF), derived for the vector and scalar potentials in planar multilayer media, have been revisited to clarify some issues and misunderstandings on the derivation of these Green's functions. In addition, the range of validity of these Green's functions is assessed with and without explicit evaluation of the surface wave contributions. As it is well-known, the derivation of the CFGF begins with the approximation of the spectral-domain Green's functions by complex exponentia...
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In this paper, we present a novel, non-iterative domain decomposition method, which has been parallelized by using the message passing interface (MPI) library, and used to efficiently extract the capacitance matrixes of 3-D interconnect structures, by employing characteristic basis functions (CBFs) in the context of the finite element method (FEM). In this method, which is Failed CBFEM-MPI, the computational domain is partitioned into a number of nonoverlapping subdomains in which the CBFs are constructed b...
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AKAGÜNDÜZ, erdem; Ulusoy, İlkay (Institution of Engineering and Technology (IET), 2010-10-28)
3D object recognition is performed using a scale and orientation invariant feature extraction method and a scale and orientation invariant topological representation. 3D surfaces are represented by sparse, repeatable, informative and semantically meaningful 3D surface structures, which are called multiscale features. These features are extracted with their scale (metric size and resolution) using the classified scale-space of 3D surface curvatures. Triplets of these features are used to represent the surfac...
Citation Formats
Ö. S. Ergül, “Enhancing the accuracy of the interpolations and anterpolations in MLFMA,” IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS, pp. 467–470, 2006, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40664.