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oai:www.ideals.illinois.edu:2142/80775 2023-07-11 col_2142_5131 col_2142_8888 com_2142_5130 com_2142_8887 com_2142_234

Chew, Weng Cho Chao, Hsueh-Yung Robert 2015-09-25T20:08:06Z 2015-09-25T20:08:06Z 10000-01-01 2002 2002 A hybrid VSIE-MLFMA formulation is applied to solve for scattering and radiation solutions from wire antennas, IBC surfaces, and inhomogeneous dielectric objects. Unlike the traditional method of moments, the VSIE-MLFMA formulation has a computational complexity of O( N log N) for both CPU time and memory requirement, where N is the number of unknowns. The surface integral equation part of the formulation is extended to a full curvilinear implementation with the invention of curvilinear junction basis. The curvilinear formulation enables efficient solution for radiation and scattering from highly curved PEC structures. In order to accurately model coaxial feeds for wire antennas, a variational formulation is applied to calculate the input impedances of horizontal and vertical frill sources. Numerical simulations agree well with experimental results after correctly modeling the SMA connector as a horizontal frill source and a lossy transmission line. Moreover, succinct spectral integrals are derived for efficient calculation of the fringe capacitances, which contribute to the main differences of delta-gap and magnetic frill sources in high-frequency simulation. In addition, physics-based preconditioners and basis reduction schemes are developed to reduce iteration counts for iterative solvers. The formulation is then applied for vehicle antenna and photolithography simulations. A fast field calculation based on MLFMA significantly reduces the time for computing near and far fields radiated from vehicle antennas and photomasks. Made available in DSpace on 2015-09-25T20:08:06Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 3069981.pdf: 4856180 bytes, checksum: 5a63daa06d623a46b8b33f41486940f0 (MD5) Previous issue date: 2002 Embargo set by: Seth Robbins for item 82057 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 104 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2002. http://hdl.handle.net/2142/80775 (MiAaPQ)AAI3069981 eng Engineering, Electronics and Electrical A Multilevel Fast Multipole Algorithm for Analyzing Radiation and Scattering From Wire Antennas in a Complex Environment text Electrical Engineering Electrical Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D.