Fully Metallic Frequency Selective Surface Design via Electromagnetics Coupling Matrix

This work presents the design of fully metallic frequency selective surface (FSS) cascade filters through the use of a recently proposed electromagnetics coupling matrix approach. The filtering structure consists of a cascade of unit cells with resonators in z direction, and a periodic repetition of the structure in the x−y direction. The fully metallic cascade unit cell can be analyzed as a coupled resonator electromagnetic (EM) circuit, where evanescent fields are pushed forward by properly designed EM resonators. This coupled resonator FSS structure is especially suitable for an EM coupling matrix characterization, where all the EM couplings among resonators can be easily identified, providing valuable design information in the different parameters for the final performance of the FSS.