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Analysis and design of conformal frequency selective surfaces /
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Date
2014
Author
Dalkılıç, Akın
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An efficient analysis and design approach for conformal frequency selective surface (FSS) structures is developed. The design methodology involves the analysis of both the planar and curved FSS structures. First, planar unit cell analysis of conformal FSS models are accomplished for normal and oblique incidence cases. To prove conformal applicability of planar designs, a semi-finite analysis method is utilized. This method is based on solution of a singly periodic curved FSS structure of semi-cylinder shape possessing periodicity, curved element arrangement and finite model conditions together. The model is finite in curved direction and infinite along the axis of the cylinder. Semi-finite model analysis is a powerful solution tool to determine both transmission and reflection responses of conformal FSS structures. With the introduced design methodology for conformal FSS implementations, a narrow band FSS radome operating in Ku-band and a wide band FSS model serving as a band-pass spatial filter for X-band (8.2-12.4 GHz) signals are designed. FSS performances are verified with both planar single element unit cell solutions and semi-finite analyses of curved and planar structures. Planar prototypes of narrowband FSS model are fabricated and measured. Reasons for discrepancies between simulated and measured filtering characteristics are investigated and explained.
Subject Keywords
Frequency selective surfaces.
,
Radar cross sections.
,
Radar
URI
http://etd.lib.metu.edu.tr/upload/12617344/index.pdf
https://hdl.handle.net/11511/23612
Collections
Graduate School of Natural and Applied Sciences, Thesis
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A. Dalkılıç, “Analysis and design of conformal frequency selective surfaces /,” M.S. - Master of Science, Middle East Technical University, 2014.