A Magnetic Composite Metamaterial with Impressive Broadband High-Frequency Absorption and Low-Frequency Transmission
摘要
As modern electromagnetic (EM) systems increasingly require integrated stealth and communication functions, traditional broadband absorbers alone have become inadequate for practical applications. In this study, a transmission–absorption integrated metamaterial (ATIM) is proposed, based on a magnetic composite layer (Fe3O4@CNH/EP) and a frequency-selective surface (FSS). The structure consists of an upper magnetic composite unit array, a middle graphene FSS, and a bottom carbon-based resistive film, where the synergistic interaction among these three components induces high-efficiency high-frequency EM wave absorption and favorable low-frequency transmission. The simulations indicate that the ATIM maintains absorption above 90% across 6–18 GHz, covering part of the C-band as well as the X- and Ku-bands, while the insertion loss is < 1 dB below 1.8 GHz, corresponding to a transmission rate of approximately 80%. Furthermore, for incident angles up to 60°, the ATIM still exhibits strong absorption performance. Thanks to the centrosymmetric configuration of the resonant layer, the structure is insensitive to the polarization state of the incident wave, while also providing the advantage of a significantly reduced radar cross section. Experimental measurements on a fabricated prototype are consistent with the simulations, demonstrating that the proposed ATIM can be widely applied in EM windows with impressive high-frequency EM wave absorption and pronounced low-frequency transmission.
Graphical Abstract