A Wideband Polarization Conversion Metasurface with Stable Wide-Angle Performance

A novel polarization conversion metasurface (PCM) is proposed to achieve linearly polarized conversion with good oblique incidence performance. The unit cell of the metasurface is a composite structure consisting of a slotted hexagonal patch and two T-shaped strips. Simulation results show that the polarization conversion ratio (PCR) of the metasurface is higher than 0.9 in the frequency range of 8.46–15.28 GHz (57.45%) for perpendicularly incident TE and TM waves. Furthermore, the device exhibits excellent angular stability. Compared to the case of vertical, when the incident angle is increased to 46°, the bandwidth reduction with PCR > 0.9 is 3.86% for TE incident, and 4.14% for TM incident wave.

I. Introduction

Metasurfaces are artificially designed planar patterns with many exotic electromagnetic (EM) properties that cannot be found in conventional materials, such as negative refractive index [1], inverse Doppler effect [2], and perfect imaging [3]. Recently, metasurfaces have become a new option for designing polarization converters due to their property of flexibly adjusting the polarization state of EM waves. By reasonably designing the unit cell and its arrangement, we can achieve metasurface-based polarization converter with different polarization conversion (PC) functions, such as linear-to-linear [4] and linear-to-circular [5] polarization converter.