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Mittra, Raj Gedney, Stephen Douglas 2011-05-07T12:34:36Z 2011-05-07T12:34:36Z 10000-01-01 1991 The focus of this thesis is on the development of parallel algorithms which exploit hypercube multiprocessor computers for the solution of the scattering of electromagnetic fields by bodies situated in an unbounded space. Initially, algorithms based on the method of moments are investigated for coarse-grained MIMD hypercubes as well as fine-grained MIMD and SIMD hypercubes. It is shown that by exploiting the architecture of each hypercube, supercomputer performance can be obtained using the JPL Mark III hypercube and the Thinking Machine's CM2. Second, the use of the finite element method for the solution of the scattering by bodies constituted of composite materials is presented. For finite bodies situated in an unbounded space, the use of an absorbing boundary condition is investigated. A method known as the mixed-$\chi$ formulation is presented, which reduces the mesh density in the regions away from the scatterer enhancing the use of an absorbing boundary condition. The scattering by troughs or slots is also investigated using a combined FEM/MoM formulation. This method is extended to the problem of the diffraction of electromagnetic waves by thick conducting and/or dielectric gratings. Finally, the adaptation of the FEM method onto a coarse-grained hypercube is presented. The parallel algorithm is shown to be highly efficient by mapping the finite elements using a domain decomposition technique and solving the sparse matrix expression using the preconditioned biconjugate gradient method. Made available in DSpace on 2011-05-07T12:34:36Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9136594.pdf: 14292645 bytes, checksum: e60d030febd7e31865cc032e084b0869 (MD5) Previous issue date: 1991 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:42:49Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:18:39-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9136594 (UMI)AAI9136594 http://hdl.handle.net/2142/20277 eng Copyright 1991 Gedney, Stephen Douglas Engineering, Electronics and Electrical Solution of open region electromagnetic scattering problems on hypercube multiprocessors text Electrical and Computer Engineering Electrical and Computer Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D.