Design of Dual-Polarized Frequency Selective Structure With Quasi-Elliptic Bandpass Response

This letter is concerned with the design of a dual-polarized frequency selective structure (FSS) consisting of a two-dimensional periodic array of dielectric-filled concentric waveguides. The operating principle and design guidelines of this dual-polarized structure are explained. A design example is provided, which shows a good agreement between simulated and measured results. It is demonstrated that the proposed FSS exhibits quasi-elliptical frequency response under dual polarizations, and its filtering performance is insensitive to the incident angle of incoming plane waves.