Design and Implementation of High Efficiency and Broadband Transmission-Type Polarization Converter Based on Diagonal Split-Ring Resonator

In this paper, the design and implementation of a three-layer linear polarization converter having broadband and asymmetric transmission (AT) properties is demonstrated. A 3.2 mm thick transmission-type polarization converter with two separate operating frequency bands is obtained with a cut-wire sandwiched by two layers of diagonal split-ring resonator (DSRR). The asymmetric transmission property can be realized by rotating the upper and lower DSRR dislocation, and its physical mechanism can be explicated by the Fabry-Perot-like interference effect. Experimental results are presented and compared to numerical simulations, and they demonstrate that the proposed polarization converter has a significantly polarization conversion ratio over 0.8 in frequency bandwidths 8-11 GHz and 17-21 GHz for the forward and backward incidences. The proposed polarization converter has a great potential to be used as an asymmetric transmission radome or diode-like device in microwave domain.