An Ultra-Thin, Triple-Band, Incident Angle-Insensitive Perfect Metamaterial Absorber

Abstract

We created an ultra-thin, triple-band incident angle-insensitive perfect metamaterial absorber (MMA) with a metallic patch and a continuous metal ground isolated by a central dielectric substrate. The top metallic patch, placed across the edges of the 0.58 mm thickness Rogers RO4003C (lossy) substrate, forms the bulk of the projected absorber’s ultra-thin layer. Nonetheless, absorption is exceedingly strong, covering C-band, X-band and K-band and reaching levels of 97.8%, 99.9%, and 99.9%, respectively, under normal and even oblique (0° to 45°) incident conditions. In chosen ranges of frequency of 6.24, 10.608, and 18.624 GHz for both TM and TE mode, the displayed Q-factors were 62.4, 17.68, and 26.61, respectively. We correspondingly calculated the RAB (relative absorption bandwidth) to evaluate absorption performance. An equivalent circuit proved its performance capabilities, indicating that it would produce a high-quality MMA from ADS software. Furthermore, the absorber’s performance has been verified in free space on a sample being tested using a different array of unit cells. Moreover, the proposed structures with HFSS simulators to display the MMA’s absolute absorption at each absorption peak are somewhat inconsistent with the results of the CST simulator. Because of its superior performance, the ultra-thin absorber is suited for a wide range of applications, including satellite applications such as radar systems, stealth technology, imaging, and electromagnetic interference reduction.

Quad-Band Metamaterial Perfect Absorber with High Shielding Effectiveness Using Double X-Shaped Ring Resonator

“…The combined effects of these peaks created optimal absorbance throughout several resonance frequency regions [ 28 ]. According to the literature, various strategies have been proposed to raise the quality factor of these sensors, such as printing devices using a smaller loss of dielectric substrates [ 14 , 29 ]. It is feasible to adjust for a high-quality factor based on absorptions [ 30 ].…”

“…The proposed model displayed quad-bands with an absorption coefficient of 99.9%, 99.9%, 99.9%, and 99.8% for resonance frequencies at 4.87 GHz, 7.49 GHz, 11.78 GHz, and 13.09 GHz for the TE and TM modes. The FWHM values for both modes at all frequencies were 0.2, 0.8, 0.5, and 0. to raise the quality factor of these sensors, such as printing devices using a smaller loss of dielectric substrates [14,29]. It is feasible to adjust for a high-quality factor based on absorptions [30].…”

Ultra-thin wideband frequency tunable metamaterial absorber and its application for antenna radar cross section reduction

“…The absorbing capacity of MMAs arises from electromagnetic resonance, giving rise to its inherent limitation of a significantly narrow absorption bandwidth. While a considerable number of broadband or ultrabroadband passive metamaterial absorbers have been developed, the majority of them are unable to mitigate the increase in profile thickness [10][11][12][13][14]. In the design of MMAs, three critical factors that require attention are absorption bandwidth, absorption rate, and profile thickness.…”

An Optically Transparent Metamaterial Absorber with Tunable Absorption Bandwidth and Low Infrared Emissivity

“…However, while radar stealth materials require high absorption and low reflectivity, IR stealth materials require low absorption and high reflectivity, which makes compatible designs very difficult. Moreover, the coverings may damage the original properties of the radar-absorbing materials, resulting in a decrease in absorbing performance [13][14][15].…”