3D printed perforated conformal broadband frequency selective surface-based absorber

Abstract

This paper presents a 3D printed lightweight conformal broadband frequency selective surface (FSS)-based electromagnetic absorber. The proposed geometry is designed using a periodic pattern of resistive inks deposited on a perforated dielectric substrate, supported by an air gap and a ground plane, which demonstrates a wide absorption bandwidth (> 90% absorptivity) of 109.81% covering the X, Ku, and K bands (8.5–29.2 GHz). The topology is polarization-insensitive as well as maintains stable performance under oblique incidence up to 45° for TE mode and 30° for TM mode. An equivalent circuit model and surface current analysis are presented to elucidate the underlying absorption mechanism. A prototype has been developed using a cost-effective 3D printing technology, and its measured responses show excellent agreement with the simulated results. Furthermore, the geometry has been conformed to a cylindrical shape with different curvature angles, and its absorption responses are verified, demonstrating promising real-world applications in radar cross-section (RCS) reduction and electromagnetic shielding. © 2025 Elsevier B.V., All rights reserved.