Derivation of green’s functions for spherically stratified media using an equivalent two port network model /

Yeni, Burcu
Derivation of dyadic Green’s functions for a variety of geometries is a problem frequently faced in different fields of electromagnetics including the analysis and design of antennas, waveguides and resonators. In the case of spherically stratified antenna, waveguide or resonator structures, the analytical derivation process of dyadic Green’s functions is often extremely complex while numerical solutions comprise heavy workload. In this thesis, an equivalent two-port network model, which was first developed for the analysis of stratified planar structures and then extended to stratified cylindrical and spherical structures, is utilized to derive the spectral-domain Green’s functions of spherically stratified media including a spherical microstrip antenna and a human head modeled as a spherical multilayer dielectric. This equivalent circuit model approach is applicable to multiple geometries and enables the utilization of simple network analysis techniques for the derivation of Green’s functions in these geometries.


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Full wave analysis of microstrip lines at microwave frequencies is performed by using method of moments in conjunction with closed-form spatial domain Green’s functions. The Green’s functions are in general Sommerfeld-type integrals which are computationally expensive. To improve the efficiency of the technique, Green’s functions are approximated by their closed-forms. Microstrip lines are excited by arbitrarily located current sources and are terminated by complex loads at both ends. Current distributions ...
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Numerical analysis of periodic structures in layered media is usually accomplished by using Method of Moments which requires the formation of the impedance matrix of the structure. The construction of this impedance matrix requires the evaluation of the periodic Green’s function in layered media which is expressed as an infinite series in terms of the spectral domain Green’s function. The slow converging nature of this series make these kinds of analysis computationally expensive. Although some papers have ...
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Citation Formats
B. Yeni, “Derivation of green’s functions for spherically stratified media using an equivalent two port network model /,” M.S. - Master of Science, Middle East Technical University, 2015.