Broadband polarization reconfigurable antenna based on metasurface

In light of the growing demand for multifunctional antennas in modern communication systems, a broadband polarization reconfigurable antenna loaded with a metasurface is proposed. The antenna comprises an upper layer featuring a circular hole cut out from a chamfered square metasurface and a lower layer consisting of a dual-slot microstrip antenna. The proposed antenna can maintain a broad impedance bandwidth while realizing different polarization modes such as left-hand circular polarization(LHCP) and right-hand circular polarization(RHCP) and linear polarization(LP) by rotating the metasurface around the center of the antenna. The measured results show that the maximum impedance bandwidth achieved for the circular polarization(CP) state of this metasurface antenna is 51.4%(2.99-5.04 GHz), while its maximum 3 dB axial ratio bandwidth reaches 21.7%(3.73-4.64 GHz). For the LP state, the maximum impedance bandwidth is recorded at 49.0%(2.97-4.90 GHz), with cross polarization discrimination exceeding 20 dBi and gain consistently above 7.5 dBi across the operational frequency band. This antenna effectively facilitates transformations between CP and LP within a broad impedance bandwidth and boasts exceptional performance.