A sub-wavelength polarization sensitive band-stop FSS with wide angular response for X- and Ku-bands

A sub-wavelength second-order band-stop frequency selective surface (FSS) is presented. The single layer FSS has a band reject operating mode for TE- and TM-polarizations incidence. Miniaturization of the FSS unit cell is achieved by coupling two resonators separated by single FR4 substrate. The unit cell size of the proposed FSS is 0.25λ0 × 0.25λ0, which λ0 is the free space wavelength at the center frequency (10 GHz). As experimental results proved, the proposed FSS has a great angle independence up to 60°. An equivalent circuit model is illuminated the operating principle of designed FSS. The validity of FSS is obtained by comparing experimental results and full-wave simulations.