A Novel Miniaturized Multiband Strong Coupled-FSS Structure Insensitive to Almost All Angles and All Polarizations

Abstract

This article presents a novel miniaturized almost all-angle-insensitive strong coupled frequency-selective surface (SC-FSS) with all-polarization-insensitive multiband by introducing the different interlayer coupling patches. Two templates of a single passband and a dual passband with unit cell less than <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.03\lambda $ </tex-math></inline-formula> are adopted to bring in two stopbands on both ends of each passband. Furthermore, the corresponding equivalent circuit models are developed to explain the physical mechanism and formulate relevant design equations. Finally, a prototype of the proposed dual-passband structure is fabricated and measured to verify the results of full-wave simulation and theoretical analysis. The experiment results show that there are a lower passband working at 2 GHz and a higher passband at 5.8 GHz with a lower stopband at 4 GHz and a higher at 7.5 GHz at the ends of above passbands, respectively, which exhibits the stable performance against the variation of the incident angles (from 0° to 86°) for both TE and TM polarizations. The measurement results demonstrate that the proposed multiband SC-FSS is a good candidate for designing a high-performance antenna radome for solving electromagnetic interference (EMI) problems.