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 0.25 lambda(0) x 0.25 lambda(0), which lambda(0) 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 degrees. 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.