A Polarization-Reconfigurable Antenna with Tunable Axial-ratio Bandwidth Using Metasurface

A polarization-reconfigurable slot antenna based on metasurface (MS) with tunable 3dB axial-ratio bandwidth is presented. The antenna is composed of a circular planar slot used as source antenna and two layers of circular MS used to achieve frequency reconfiguration and polarization diversity. The two layers of MS, in sequence, placed atop the source antenna to make the antenna compact with a diameter of 75mm (0.6 λ
₀
) and thickness of 4.527mm (0.04 λ
₀
). Polarization diversity and frequency reconfiguration can be obtained by means of rotating the MSs around the central axis of the source antenna mechanically. The simulated results indicate that circular polarization (CP) satisfies a continuous frequency tuning of 17.39% with a global bandwidth of around 500MHz(21.7%) at 2.08GHz-2.58GHz, and linear polarization (LP) satisfies a 10-dB impedance bandwidth of 660MHz (28
^%
) at 2.02-2.68GHz and of 620MHz (26
^%
) at 2.04-2.66GHz can be realized.