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. © 2017 Wiley Periodicals, Inc.

Ramya S

Department of Communication Engineering

School of Electronics Engineering

Vellore Campus

Srinivasa Rao Inabathini

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Microwave and Optical Technology Letters

This article reports an ultra-thin, compact metamaterial absorber with wideband absorption at microwave frequencies. The proposed structure contains circular and rectangular split rings, and has thickness of 0.049λ0 with respect to the center frequency of the bandwidth. This structure provides wideband absorption of 3.84 GHz from 12.80 GHz to 16.64 GHz with 90% absorptivity and absorption peaks are observed at 13.2 GHz and 16.5 GHz. The full width half maximum of the structure is 5.48 GHz from 12.09 GHz to 17 57 GHz. The absorption mechanism and polarization behavior of the structure have to be studied. The proposed metamaterial absorber is sensitive to polarization but wideband absorption is attained only for specific normal and oblique angles of incidence, with reduced absorptivity. The structure has been fabricated, and the measured results match well with the simulation responses. The advantage of the proposed absorber is its wideband absorption with compact (8 mm × 8 mm size), ultra-thin (1 mm thick substrate) structure compared to that of the other existing microwave metamaterial absorbers. © 2018 Editura Academiei Romane.

Journal	Data powered by TypesetMicrowave and Optical Technology Letters
Publisher	Data powered by TypesetWiley
ISSN	0895-2477
Open Access	No