Transmission characteristics of cylindrical frequency selective fabrics with Jerusalem-shaped units

Abstract

Two kinds of complementary cylindrical frequency selective fabrics (CFSFs) with Jerusalem-shaped units were designed, constructed and analyzed in this paper. The models were built and simplified based on the thickness and equivalent electromagnetic parameters of the base fabrics. Considering the unit number difference of the models and bending directionality, the simulation processes were separately carried out using the waveguide method in HFSS software. Based on the preparation of preliminary planar prototypes and corresponding bending molds, different CFSF samples with the same planar units and varying bending curvature were fabricated, and the transmission characteristics were measured using the transmission method to study the influences of bending effects. The measured transmission characteristics with and without the curved mold were similar, proving the use of the curved mold exerted a negligible effect on the actual measured results of samples. For the two kinds of complementary structures, the measured and simulated S₂₁ (transmission coefficient) curves had indistinguishable differences, which justified the validity of the modeling and simulation process. Although the bending direction and curvature affected the S₂₁ curves of aperture and patch CFSFs at varying degrees, the transmission characteristics did not show drastic fluctuation and shifting, which could be attributed to the ideal symmetry of Jerusalem-shaped units and good array characteristics.