An efficient and low-profile metasurface-based polarization converter with linear and circular polarization efficiencies for X- and Ku-Band applications

Abstract

In this study, a metasurface-based linear and circular polarization converter operating on the reflection mode is proposed for X- and Ku-band microwave applications. The proposed converter offers an optimum performance with a polarization conversion ratio (PCR) and polarization matching ratio (PMR) greater than 93 in the bandwidth for a linearly polarized in the y-direction and right-handed circular polarized (RHCP) incident waves. Besides, the design performs over 80 PCR performance up to under oblique incidence. Moreover, the proposed converter is capable of left-handed circular polarization conversion between 7.42 and 7.68 GHz for a y-polarized incident wave. The design offers a relative bandwidth (RBW) of 71.36. The converter design is constructed with metal termination, an easily accessible FR-4 substrate and a simple design metasurface. Surface currents of the polarization converter at resonance frequencies of 8.77, 12.88 and were examined to understand its working mechanism. In addition, when the proposed design is rearranged with the appropriate geometry, the monostatic RCS reduction value in the 8.0–17.7 range is observed to be higher than 10 dB. CST program (a commercial 3D electromagnetic simulator) was used in simulations. The simulated device was fabricated with a traditional board fabrication technique. Simulation results were verified with free space measurements calibrated by the thru-reflect-line calibration procedure. The performance and efficiency of the proposed polarization converter were compared with other converters in the literature.