Design of a novel low-loss frequency scanning antenna

Alkış, Sena
In antenna engineering, frequency scanning arrays are well-known with their ability to provide low-cost electronic scanning capability. However, in many studies on these arrays, the loss of the structure is overlooked. In this study, a novel low-loss frequency scanning antenna structure is proposed. The design is a composition of a feeding waveguide utilized for frequency scanning in one plane and an array of eight elements in the other plane, which is repeated along the frequency scanning axis. The loss of the antenna is relatively low thanks to using a metallic waveguide as a beamformer and a stripline antenna as the array element. Each stripline eight-element array is fed via a novel coupling structure, which is a stripline 90-degree hybrid coupler whose input arms are inserted into the waveguide. The coupling amplitude of the structure is controlled by the insertion depth of the 90-degree hybrid couplers, which are exploited for controlling the amplitude distribution along the frequency scanning axis. The study focuses on all aspects of the design procedure and the followed methodology, as well as difficulties came across throughout the design and the methods to cope with them.


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Citation Formats
S. Alkış, “Design of a novel low-loss frequency scanning antenna,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Electrical and Electronics Engineering., Middle East Technical University, 2019.