A frequency-switchable multifunctional metasurface polarization converter via mechanical reconfiguration

Abstract This paper presents a dual-layer metasurface polarization converter with frequency-switchable and multifunctional capabilities through mechanical reconfiguration, operating in parts of the C to Ku bands. The designed structure supports both cross-polarization (CP) conversion and linear-to-circular polarization (LTCP) conversion under two operational modes: with and without a detachable metal backplate. Through mechanical reconfiguration, the device enables flexible switching between different polarization functions in non-overlapping frequency bands. When the backplate is attached, CP conversion is achieved in the 8.2–8.8 GHz and 14.2–16.6 GHz ranges, while LTCP conversion occurs in multiple bands, including 9.1–9.3 GHz, 10.4–13.2 GHz, and 17.2–17.5 GHz, Without the backplate, CP conversion is realized in the 12.9–13.9 GHz range, and LTCP conversion in the 11.6–12.4 GHz and 14.8–17.5 GHz ranges. The converter exhibits a high polarization conversion ratio (>90%), a low axial ratio (<3 dB), and stable performance under oblique incidence up to 30°. By avoiding active components such as PIN diodes and functional materials, the design offers advantages in cost, power handling, and structural simplicity, making it suitable for modular and large-scale applications in modern electromagnetic systems.