A compact ultra‐thin ultra‐wideband microwave metamaterial absorber

Abstract

This study presents a new, ultra‐thin compact microwave metamaterial absorber for wideband applications. The proposed metamaterial absorber comprises an outer ring and inner split ring patches on the upper surface and metallic ground in the bottom surface. A dielectric FR4 substrate of thickness 1.6 mm was placed between the top patch and the bottom ground. The designed structure was ultra‐thin of λ0/13.9 thickness with respect to the centre frequency of the bandwidth. The simulation results showed ultra‐wideband absorption of 6.31 GHz from 10.36 to 16.67 GHz above 85% absorptivity, and peaks at 11.1, 13.2, 14.4 ,and 16.2 GHz and full width half maximum of 9.6 GHz. The mechanism of absorption for the proposed ultra‐wideband metamaterial absorber was studied. Also, the polarization behavior was tested under oblique and normal angles of incidence for transverse electric polarization. Due to its asymmetrical design, the proposed structure is polarization sensitive. The designed structure was fabricated and measured, and the practical results were in good agreement with the simulation results.

A Dual Band Symmetric E-Shaped Split Ring Metamaterial Absorber For RF Energy Harvesting

“…From the figure, for the various incident angles ϴ = 0 0 , 30 0 , 45 0 , 90 0 there is not much variation in the absorptivity curves. This confirms that the absorber remains polarization insensitive throughout the various angles of incident wave unlike the previous works [14][15]. The symmetrical nature of the E-shaped metamaterial absorber may also be the reason for polarization insensitivity nature of the absorber.…”

Comment on “a compact ultra‐thin ultra‐wideband microwave metamaterial absorber”

“…The structure was simulated in full wave solver Ansys HFSS by applying Floquete port excitations and periodic boundary conditions. Original author in reported absorption peaks at frequencies 11.1, 13.2, 14.4, and 16.2 GHz.…”

“…Recently, Ramya et al published an article on ultrathin, ultra‐wideband metamaterial absorber structure. The presented structure was composed of inner split ring having a thick 45° inclined metal strip embedded within a circular ring as shown in Figure .…”

“… Front view of reported unit cell of . Note that all geometrical and structural parameters are same as reported in [Color figure can be viewed at http://wileyonlinelibrary.com]…”

“…When we include cross‐polarized reflections along with co‐polarized reflections in the calculation of absorbivity, such a low value of absorption is obtained. The original author in may have ignored cross‐polarized reflections and claimed very high absorption over wide bandwidth (refer Figure in). The plots depicting co‐polarized and cross‐polarized reflections are shown in Figure .…”