Ultra-Wide Band Frequency Selective Surface: design and experimental verification of performances for wide incident angle

In the established UWB frequency range, for spatial filtering purposes a frequency selective surface is presented, simulated results showing a very large stopband between 1.78-14.32 GHz. Thus, strong polarization insensitivity is obtained with the structure and 45° angular stability for the pair: Transverse Magnetic (TM) and Transverse Electric (TE) incidence, respectively. Electromagnetic simulation was used to evaluate the performances of the structure, considering a 1.6 mm thick FR4 substrate with a 15 mm square-shaped unit cell edge. In an anechoic chamber, tests revealed an excellent match between simulation and experimental data, as well as proper device operation.