Single-layer frequency selective surface embedded with H-shape slots for stable performances

In this paper, a single-layer bandpass frequency selective surface (FSS) is proposed for L-band applications. The FSS unit cell consists of an improved hexagonal aperture unit embedded with H-shape slots. Simulated results show that the FSS obtains good frequency selective performance. Its relative bandwidth is about 55.7% using -3 dB as the criteria for the transmission coefficient. Moreover, the center frequency of the FSS structure remains stable at different incident angles for both TE and TM polarizations. The FSS retains excellent transmission characteristics even if the incident angle is up to 70 degree.