Analysis and design of wideband antenna arrays

Çapraz, Kenan
Two methods of wideband array design are studied. The aim of this study is to investigate arrays with aperiodic spacings which are designed with these methods in order to obtain wideband behavior. These methods are genetic algorithm and wavelength scaled arrays that have active regions with variable interelement spacings. Genetic algorithm is utilized for array antennas with aperiodic spacing to optimize sidelobe levels of the antenna array in wide frequency band. Wavelength scaled spacing concept in designing arrays is benefited to design array with frequency independent radiation characteristics such as constant gain and beamwidth in the operational bandwidth. MATLAB® codes are developed in order to examine array factor of designed arrays with these methods. A feed network in order to implement active region concept is designed and realized. A fabricated linear Vivaldi antenna array with designed feed network is measured and its performance is compared with simulation results.


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In this study, an optimization environment based on heuristic algorithms supported by the multilevel fast multipole algorithm (MLFMA) is presented for different antenna problems involving either excitation or geometry optimizations. The heuristic algorithms are implemented in-house by aiming more effective interactions between electromagnetic solvers and optimization algorithms, instead of black box interactions. Excitation optimizations of various array geometries for desired radiation characteristics are ...
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Citation Formats
K. Çapraz, “Analysis and design of wideband antenna arrays,” M.S. - Master of Science, Middle East Technical University, 2014.