Efficient MOM analysis of printed structures by utilizing characteristic modes

Çetin, Metehan
In recent years, the theory of characteristic modes has been widely used for antenna design purposes. This theory provides physical insight about scattering and radiating properties of conducting bodies. In this thesis work, a MATLAB code is developed for analyzing printed structures by using characteristic mode theory. Characteristic modes of printed structures can be calculated by using the Method of Moments (MoM) matrix corresponding to the structure. To generate the MoM matrix, the electric field integral equation is discretized by using Rao Wilton Glisson (RWG) basis functions and Galerkin's testing procedure. First, characteristic mode analysis of an ultra wide band planar bevel-shaped quasimonopole antenna structure is made by using the developed code. The results are compared with the results obtained from a commercially available electromagnetic simulation software called FEKO. After verifying the accuracy of the developed code with this comparison, the code is extended to include the analysis of antennas printed on dielectric substrates. For this purpose, discrete complex image method is utilized to obtain the spatial domain Green's functions in layered media. The analysis of rectangular microstrip antennas are performed by using the developed code and the results are compared with FEKO.  


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Citation Formats
M. Çetin, “Efficient MOM analysis of printed structures by utilizing characteristic modes,” M.S. - Master of Science, Middle East Technical University, 2016.