A multiband and multifunctional metasurface polarization converter using split-ring resonators

Abstract

In this paper, a multiband and multifunctional metasurface polarization converter is proposed based on split-ring resonators, which can effectively convert linearly polarized (LP) wave to cross-polarized and circularly polarized (CP) wave in the part of C to K bands. The simulation results show that when the structure has a metal bottom plate, the cross-polarization conversion can be achieved in three frequency bands, 7.43–10.49, 10.84–14.66, 16.32–18.19 GHz, the polarization conversion ratio >90%, and the conversion from LP-to-CP (LTC) can be achieved in five frequency bands of 7.27–7.4, 14.72–14.9, 15.24–16.05, 18.24–18.79 and 18.97–19.47 GHz, the axial ratio (AR) is less than 3 dB, and the polarization converter can maintain good performances in 45° incidence angle. When there is no bottom metal plate, the LTC function can be achieved in two frequency bands, 8.32–9.72 and 11.24–17.18 GHz, the AR is less than 3 dB, and with the increase of the incident angle, the first frequency band of the LTC conversion is almost unchanged, but the second frequency band is split into two bands and then stabilized. The mechanism of polarization conversion generation was analyzed, and the polarization converter can be widely used in microwave communication and radar stealth fields.