Analysis and design of wideband antenna arrays

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Date

2014

Author

Çapraz, Kenan

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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.

Subject Keywords

Antennas (Electronics)., Broadband communication systems., Genetic algorithms., Antenna arrays.

URI

http://etd.lib.metu.edu.tr/upload/12616874/index.pdf
https://hdl.handle.net/11511/23336

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Graduate School of Natural and Applied Sciences, Thesis

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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.