Using Homogeneous Equivalent Parameters in Finite Element Models of Curved Metamaterial Structures

Abstract

We report on the experimental verification of the employment of equivalent parameters in a 2D finite element model to describe absorptivity of curve-shaped, large-scale metamaterial structures. Equivalent homogeneous optical parameters were retrieved from experimental measurements of flat metamaterial sheets with square resonators of 8 and 9 mm and used in a 2D FE model to obtain the absorptivity of curved structures with similar metamaterial unit cells. The curved structures were experimentally characterized and showed good agreement with the model. The tremendous simplification made possible by simulating complex structures as homogeneous materials makes the method very attractive for designing large-scale electromagnetic shields and absorbers.

CNT Conductive Epoxy Composite Metamaterials: Design, Fabrication, and Characterization

“…Lower conductivity (0.862 S/m) than metal conductors may have contributed to the widening of the absorption curves, providing a greater band of frequency absorption. Larger square arrangements showed absorption bands at lower frequencies, as seen in previous work [ 15 , 18 ]. In addition, as observed experimentally in THz band [ 18 ], the model shows a decrease in absorption magnitude as the square dimensions (and resonant frequency) decrease, everything else being constant.…”

“…Using classical transmission line theory and the scattering parameters detected from the VNA, the samples were characterized in terms of absorbance, reflectance, and transmittance. The overall results showed that CNT/PANI composites proved useful for microwave absorption purposes over the Ku-Band in the microwave frequency range (12)(13)(14)(15)(16)(17)(18), with shielding effectiveness up to 28% [4].…”

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“…The metamaterial patterns must be smaller than the wavelength of incident EM radiation. A common metamaterial configuration that has been studied extensively is the conductive square array [ 10 , 15 , 16 , 17 , 18 ]. Figure 1 provides a schematic of this configuration, highlighting the periodic patterned conductive material layer, the dielectric spacer, and the ground plane.…”

Rapid prototyping of microwave metasurfaces by ink-jet printing on polyester (PET) transparencies

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