A new design for an ultra-wideband microwave metamaterial absorber

A flexible triple-band and polarization-insensitive rectifying metasurface (RMS) is presented in this article. The surface consists of three parts: a periodic metal unit with integrated diodes, a DC filter composed of series inductor and parallel capacitor, and a load resistor. Due to the direct integration of rectifying diodes and interconnected branches within and between the units, complex matching networks can be eliminated and the overall structure is simplified. A 6×6 array is fabricated and measured. The results show that at a low input power of 0 dBm, the RMS has efficiency of 51.81%, 44.25%, and 42.01% at 2.9 GHz, 5.2 GHz, and 5.77 GHz, respectively. The efficiency remains consistent under different polarization angles, demonstrating the polarization insensitivity property of RMS. Additionally, the flexible substrate enables high efficiency in the S-band and Wi-Fi bands even under a certain range of bending, revealing its superior flexibility and adaptability. Therefore, it is well suited for ambient energy harvesting and wireless self-powered miniaturized IoT devices.

Section: Introductionmentioning

confidence: 99%

Triple-band and polarization-insensitive rectifying metasurface with flexible substrate

Gui,

Xie,

Deng

et al. 2024

“…directly available in nature, such as negative permittivity and permeability and anomalous reflection/refraction. These properites lead to various potential applications including super-scattering [3], perfect absorption [4], super-lensing [5,6], filters [7,8], waveguides [9], magnetic resonance imaging [10], and wireless power transfer [11,12]. In addition to the exceptional properties of metamaterials, they may be designed to be tunable [13].…”

Section: Introductionmentioning

confidence: 99%

Effect of mechanical nonlinearity on the electromagnetic response of a microwave tunable metamaterial

Mahabadi¹,

Goudarzi²,

Fleury³

et al. 2022

Tunable metamaterials functionalities change in response to external stimuli. Mechanical deformation is known to be an efficient approach to tune the electromagnetic response of a deformable metamaterial. However, in the case of large mechanical deformations, which are usually required to fully exploit the potential of the tunable metamaterials, the linear elastic mechanical analysis is no longer suitable. Nevertheless, nonlinear mechanical analysis is missing in the studies of mechanically tunable metamaterials. In this paper, we study the importance of considering nonlinearity in mechanical behavior when analyzing the response of a deformable metamaterial and its effects on electromagnetic behavior. We consider a microwave metamaterial formed by copper four-cut split ring resonators on a Polydimethylsiloxane (PDMS) substrate. Applying both displacement and force stimuli, we show that when the deformation is large, more than 10 percent strain, the use of nonlinear analysis considering the geometrical and material nonlinearities is imperative. We further show that the discrepancies between the linear and nonlinear analyses appear in overestimating the stress, underestimating the tunability of the metamaterial responses, and mispredicting the negative permeability regions.

“…In recent years, scholars have carried out a lot of research on absorbers, such as narrow-band absorbers [6,7] and wideband absorbers [8][9][10][11][12][13][14]. Compared with narrow-band absorbers, wideband absorbers have a wider range of applications.…”

Section: Introductionmentioning

confidence: 99%

Dual-band absorber using low-profile multi-mode resonant units for controllable bandwidths

Huang¹,

Wu²,

Deng³

et al. 2022

A dual-band quasi-single-layer absorber based on multimode resonance is proposed. Different from the traditional multi-substrate or multi-resonator composite structure, by virtue of stub- and slot-loaded technologies, only one single-substrate printed resonator is utilized to achieve multi-mode resonant characteristics for two absorption bands. The bandwidth of the two absorption bands can be adjusted by structural parameters. Through the detailed analysis of the surface current distribution in different modes, the generation principle of the multi-mode dual-band characteristic is revealed. Finally, the dual-band absorber is fabricated and measured, achieving dual-band absorptions in the frequency range of 7.64–10.8 GHz and 15.04–17.32 GHz with fractional bandwidth (FBW) of 34.3% and 14.1%, respectively. The advantages of low-profile simple structure and controlled dual bandwidth make it very suitable for radar detection and stealth fields.