Low Profile Ultrathin Wide-Passband Polarization-insensitive Frequency Selective Surface with wide angular stability

In this paper, a low profile, ultrathin, wide passband, polarization insensitive, wide angular stable frequency selective surface (FSS) is proposed. The structure is realized on a two-sided copper on Roger’s RT 5880 substrate with 0.51 mm thickness. The top layer design consists of a combination of slotted circle with quad arcs along with cross bars at the center with diagonal tilts at the corner. On the bottom layer, an elliptical-shaped patch is placed at the center. This elliptical patch at the bottom layer of FSS helps to realize the wide pass-band response. The pass-band bandwidth ranges from 8.45 to 9.45 GHz centered at 8.96 GHz. The proposed FSS is polarization insensitive. The structure provides angular stability till 45° of incident angle for Transverse Electric (TE) and Transverse Magnetic (TM) modes of operation. The prototype of FSS is fabricated with an array of 10 x 10 unit cells. The simulated and measured results are found to be in good agreement.