A Dual-Band Zero-Index Metamaterial Superstrate for Concurrent Antenna Gain Enhancement at 2.4 and 3.5 GHz

ABSTRACT

The classical printed monopole antenna exhibits wideband operation with low gain and an omnidirectional radiation pattern. In order to boost the gain of the antenna at two frequency bands, a novel dual-band zero-index metamaterial (ZIM) based on both electric and magnetic resonance is developed. The printed monopole is also backed by a metallic ground plane for unidirectional radiation pattern towards boreside. The presented unit cell is comprised of two Schurig split-ring resonators nested together in such an arrangement that it leads to a zero refractive index at two distinct frequencies. Using the proposed design methodology, a ZIM is designed operating at 2.4 and 3.5 GHz. To substantiate the improvement in gain, the proposed design is fabricated and used with a cavity-backed printed monopole antenna. The metamaterial superstrate increases the measured realized gain of the printed monopole antenna by 3.2 dB at 3.5 GHz and by 2.5 dB at 2.4 GHz, in agreement with simulations.

KEYWORDS:

• Dual-band
• Gain enhancement
• Mu-near zero
• Nested Schurig SRRs printed monopole antenna
• Zero index metamaterial

ACKNOWLEDGEMENTS

The authors are thankful to Rogers Corporation for providing free boards.

Additional information

Notes on contributors

Zain Haider

Zain Haider received his MS degree in electrical engineering from the National University of Sciences and Technology in 2017 and currently pursuing his PhD degree in electrical engineering at University of Rennes since 2018. His main research interests are metamaterials and microdosimetry.

Muhammad U. Khan

Muhammad U Khan received his MS degree in electrical engineering from GIK Institute of Engineering Sciences and Technology in 2008 and received his PhD in electrical engineering from King Fahd University of Petroleum and Minerals. He is currently serving as assistant professor at National University of Sciences and Technology. Email: [email protected]

Hammad M. Cheema

Hammad M Cheema received his MS degree in 2004 from Technical University of Denmark and received his PhD in electrical engineering from the Eindhoven University of Technology in 2010. He is an assistant professor at National University of Sciences and Technology and currently serving as head of Department of Research Institute of Microwave and Millimeter Wave Studies. Email: [email protected]