Leaky-Wave Radiations with Arbitrarily Customizable Polarizations Based on Spoof Surface Plasmon Polaritons

Spoof surface plasmon polaritons (SSPPs) can be converted to leaky-wave radiations by a spoof surface plasmon (SSP) waveguide with periodically modulated surface impedance, which is also known as a SSPP leaky-wave antenna (LWA). However, most of the reported SSPP LWAs can only radiate electromagnetic (em) waves with linear polarizations parallel to the SSP waveguide due to the limitation of perpendicular grooving structures, and the polarizations of LWA radiations are difficult to arbitrarily design. We propose an efficient method to achieve the leaky-wave radiations with arbitrarily customizable polarizations based on an alternative SSPP LWA, which is made of a periodically modulated SSP waveguide with bilateral 45 degrees-tilted grooves to generate two orthogonally polarized em waves. The grooves on both sides of the SSPP LWA can be designed with proper displacement to provide the required phase difference between two orthogonally polarized radiation waves in order to customize the polarization of the leaky-wave radiations. Both simulation and experimental results are provided to validate the feasibility of tailoring arbitrary polarizations for the radiation waves based on the proposed SSPP LWA.