Multiband Metasurface Based Polarization Converter for Linear and Circular Polarization Conversion

This study presents a multifunctional metasurface capable of achieving polarization conversion across narrow and wide frequency bands. The proposed polarization converter comprises a diagonal strip, a V-shaped resonator, and an Eshaped resonator, fabricated on a 1.6 mm thick FR-4 substrate. The design demonstrates orthogonal polarization conversion in the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$8.45-8.55 \text{GHz}$</tex> range with a maximum polarization conversion ratio (PCR) of 97.5%, as well as wideband orthogonal polarization conversion in the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$11.5-12 \text{GHz}$</tex> and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$16.5-17.73 \text{GHz}$</tex> bands, achieving PCRs exceeding 90 % and 95 %, respectively. Additionally, the metasurface converts linearly polarized waves to left-hand circular polarization within the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$9.5-10 \text{GHz}$</tex> frequency range. Beyond polarization conversion, the structure functions as a metareflector, preserving the handedness of circularly polarized waves upon reflection. This metasurface holds significant potential for applications in satellite communications, radar systems, and 5 G networks due to its multifunctional capabilities with compact design.