Integrated Electromagnetic Wave Absorption-Transmission via 3D-Printed Bilayered Metamaterial

Achieving integrated absorption and transmission of electromagnetic waves (EMW) remains challenging due to the inherent contradiction between the high loss required for absorption and the near-zero loss essential for transmission. To overcome this limitation, we designed a bilayered 3D-printed metamaterial consisting of a top Schwarz-P-structured dielectric absorber and a bottom frequency-selective surface (FSS) acting as a reflective filter. The synergistic material composition combined with triply periodic minimal surface geometry enables excellent impedance matching, facilitating low-frequency transmission and high-frequency absorption. The FSS transmits low-frequency signals while reflecting high-frequency waves for re-absorption, allowing the metamaterial thickness to be reduced by half without compromising absorption performance. The resulting structure, with a total thickness of only 6 mm, achieves a transmission bandwidth of 3.5 GHz (3.5–7 GHz) and an absorption bandwidth of 6 GHz (12–18 GHz), outperforming existing frequency-selective rasorber in both bandwidth and thickness. This material demonstrates strong potential for applications in low-observable radomes and modern communication systems.