Circular metasurface based on SSPP and application on beam width enhancement of slot antenna
A circular metasurface that consists of twelve gradually increasing two-sided metallic grooves and an ultra-thin flexible dielectric film is theoretically and experimentally demonstrated based on the s poof surface plasmon polaritons (SSPPs) in the microwave frequency. The dispersion characteristics of the SSPPs structure are analyzed by the length of grooves study. The circular metasurface provides a way to convert spatial propagating waves to the SSPP waves. For application, we design a novel and attractive waveguide slot antenna loaded with the circular metasurface to enhance the beam width. To demonstrate the design, a metasurface waveguide slot antenna device easily implemented using common printed circuit board fabrication method is fabricated and measured, and measurement agrees well with simulation.