Design and Analysis of a Bow-Tie Slot-Coupled Wideband Metasurface Antenna

Abstract

A wideband metasurface antenna is designed and analyzed in this letter. The dual-layer metasurface is fed with a stubloaded bow-tie-shaped slot. The dual-layer metasurface is fed with a stub-loaded bow-tie-shaped slot. By using the coplanar waveguide feeding structure, three resonant modes (TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">10</sub> , TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">20</sub> , and TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">30</sub> ) are excited, and a wide operation band is obtained. Besides, in order to achieve a high front-to-back ratio and enhance the realized radiation gain in the whole band, a shorted reflector is implemented behind and close to the slot. The proposed antenna with an overall thickness of 0.13λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> (λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> is the free-space wavelength at the central operation frequency) is simulated, fabricated, and measured. Measured results show that the antenna has a wide impedance bandwidth from 6.15 to 10.75 GHz (54.4%) with good radiation performance.