A Wideband DNG Metamaterial Absorber with WS-Shaped Split Ring Resonator for X- and Ku- Frequency Band Applications

AbstractA novel compact microwave metamaterial absorber structure with a wide bandwidth is proposed. The absorber structure is designed on an FR4 substrate with a 2.4 mm thickness. The metamaterial absorber unit cell design consists of a combination of W and S-shaped structures in which splits are incorporated to have the effect of a split ring resonator. The proposed unit cell structure is designed to have a wide absorption band, which includes the X and Ku frequency bands. The optimized dimension of the unit cell is 0.071 λ0 × 0.71 λ0 where λ0 is the wavelength of the center frequency of the absorption band. The WS-shaped structures are oriented to absorb TE and TM waves for a wide range of polarization angles. The simulation results of the unit cell have shown absorption above 95% from 10.48 to 13.28 GHz. In addition, the absorber has an efficiency above 92% for incidence angles from 0° to 60° for fixed polarization. The unit cell structure and array are fabricated, and measurements are performed. The simulation and measured results have shown good agreement. The proposed metamaterial can be used in defense and radar surveillance applications.KEYWORDS: Metamaterial absorberPolarizationPolarization insensitiveSplit ring resonatorWideband Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationNotes on contributorsRamesh AmugothuRamesh Amugothu received his Btech degree in electronics and communication engineering from Jawaharlal Nehru Technological University in Hyderabad, India, in 2013, and an Mtech degree in the department of electronics and communication engineering from the National Institute of Technology Surathkal, India, in 2016. Currently, he is pursuing his PhD degree in the department of electronics and communication engineering at the National Institute of Technology, Warangal, India. He has over 3 year’s research/academic experience. He is an IEEE student member, voice chair for IEEE-MTT and IEEE-APS at NIT Warangal, India. Corresponding author. Email: ar720057@student.nitw.ac.inVakula DameraVakula Damera received a bachelor’s degree in electronics and communication engineering from Nagarjuna University, Andhra Pradesh, India. And a master’s degree from the Birla Institute of Technology, Mesra, India. With a focus on microwave specialization in 1992 and 1994, respectively, and a PhD degree in fault diagnostics of antenna arrays from the National Institute of Technology, Warangal, India, in 2010. She is a professor at the National Institute of Technology, Warangal. She has authored 81 papers for international conferences and journals. Her areas of interest include phase array antennas, ultra-wideband antennas, multiband antennas, fault diagnostics, neural networks, and metamaterials. She has over 30 years research/academic experience in the areas of RF and microwave systems/components and has executed over 15 projects sponsored by DST/AICTE/MHRD or Other Sponsored R&D project. Email: vakula@nitw.ac.in