Analysis of spherical-rectangular printed antennas and antenna arrays using cavity model

Demir, Oğuz
Printed antennas are commonly used since these antennas are preferred in many applications due to their advantageous properties. In order to employ these antennas in such applications, a thorough investigation and analysis are generally required. Although this can be implemented with fully numerical methods for the sake of high accuracy, the complex calculations required in the process lead to heavy computational load, hence generally demands high quality simulation software. In this thesis, the spherical-rectangular antennas mounted on a conducting sphere are analyzed by employing the cavity model as the basic analysis method, and the equivalent magnetic currents are derived. The radiation of equivalent currents in the presence of the conducting sphere is modeled by means of spherical wave harmonics, and their coefficients are obtained in the spectral domain. The approach is applied to both single element and array structures and resulting radiation patterns are examined and compared with commercial software simulations. In addition, vector rotation and coordinate mapping techniques are employed to extend the study to arrays consisting of elements with equal geometry and feeding. 


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Citation Formats
O. Demir, “Analysis of spherical-rectangular printed antennas and antenna arrays using cavity model,” M.S. - Master of Science, Middle East Technical University, 2017.