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Radiation and scattering investigations of some canonical problems: Pulse maximization for wire structures and finite difference analysis of two-dimensional microstrip structures
Abstract
This dissertation develops several novel approaches to radiation and scattering problems in the time and frequency domains. The time domain work utilizes a maximization procedure that produces results that are optimum in some sense. Several applications of this procedure are explored in the first part of the dissertation. The optimum solutions maximizing the far-zone response of dipole structures are presented. The maximization problem is first applied to a dipole array operating in the receiving mode and in series with a loaded feed network. The optimum solution represented by the incident plane wave sets an upper bound on the maximum power receivable by the array. The maximization problem is then used as a means of target discrimination and its results are compared to those produced by the Extinction Pulse method. An attempt to improve the transient response of a single wire is also investigated through the use of lumped loading. The second part of the dissertation is devoted to the analysis of infinite arrays of two-dimensional microstrip elements using the finite difference method. The procedure is used to study the behavior of three configurations of planar strips over a dielectric substrate in an infinite array environment. These configurations include the "dipole" element, the "microstrip" element and the "microstrip" element over an inhomogeneous substrate. For each configuration, calculated results are presented with special attention given to antenna characteristics such as input impedance and scan performance. Verification of the finite difference approach for these problems is achieved by comparing its results with those obtained using other methods available in the literature.
Subject Area
Electrical engineering
Recommended Citation
Bayard, Jean-Pierre Raymond, "Radiation and scattering investigations of some canonical problems: Pulse maximization for wire structures and finite difference analysis of two-dimensional microstrip structures" (1990). Doctoral Dissertations Available from Proquest. AAI9035378.
https://scholarworks.umass.edu/dissertations/AAI9035378