Design and Analysis of a Broadband Microwave Metamaterial Absorber

Abstract

In this article, a broadband metamaterial absorber suitable for the S, C, and X bands is designed and manufactured. The absorber is made of FR-4 substrate, resonant metal structure, lumped resistance, and metal backplate, has a unit size of 0.11λ L , and a total thickness of 0.084λ L . The absorption principle of the absorber is analyzed using equivalent medium theory and parametric research. The calculation results show that the absorber achieves more than 90% broadband absorption (relative bandwidth of 130%) between 2.7 GHz and 12.7 GHz, has a good polarization angle and incidence angle insensitivity, uses electromagnetic resonance to explain its absorption characteristics, and experiments confirm that the absorber has good broadband absorption. The proposed absorber has higher absorption and simpler construction than the previously described broadband absorber, and it has the potential for practical applications in EMC, radar, and electromagnetic protection.

A Wide-Angle, Polarization-Insensitive, Wideband Metamaterial Absorber With Lumped Resistor Loading for ISM Band Applications

“…However, the losses introduced by the lumped resistors might not suffice to achieve a sufficiently wide absorption bandwidth. Fortunately, this challenge can be addressed by designing the absorber with a layer of flexible foam (air gap) or rubber placed between the substrate and ground plane [38]- [47]. In [38], an MM absorber loaded with four lumped resistors and an air layer is designed over a frequency range from 860 to 960 GHz, achieving a relative bandwidth of 14%.…”