Active Metasurface-Based Wideband Polarization Converter With a Switchable Notch

We introduce a new metasurface-based wideband polarization converter with a switchable notch band. Unlike previous structures, the proposed structure utilizes the properties of p-i-n diodes to offer switchable functionalities between single/dual-frequency bands. Specifically, during the
on-
state of diodes, an incident linearly polarized (LP) plane wave of frequency range 4.87–11.41 GHz is converted into an orthogonally linearly polarized (OLP) wave. Conversely, when the p-i-n diodes are set in their
off-
state, the structure converts the LP plane wave into an OLP wave within two adjacent frequency bands (4.80–7.31 GHz and 9.82–11.43 GHz) separated by a notch region (7.44–7.55 GHz). The notch band is characterized by an LP-full reflection behavior that can be exploited for stealth antenna applications. The working principle of the proposed device and its physical mechanisms are discussed. Finally, a prototype is fabricated and measured and the experimental results confirm the effectiveness of the proposed structure.