Loaded frequency selective surfaces using substrate integrated waveguide technology

In this paper, A novel miniaturized bandpass loaded frequency selective surface (LFSS) using substrate integrated waveguide (SIW) technique is presented. A S-band bandpass FSS is designed, in which each periodic cell consists of a square loop resonator loaded with four ceramic chip capacitors. The proposed LFSS provides high transmission at 2.45 GHz, and also provides very good stability to oblique incidence. Further more, there is no other frequency resonance up to 15 GHz except 2.45 GHz. The split- field update finite difference time domain (FDTD) method is used for the analysis of the unit cell of the FSS at different oblique incidence of plane waves to predict the FSS performance. By using SIW technique, the undesired coupling between FSS unit cells is eliminated, the FSS size can be miniaturized to any size by tuning the loaded lumped elements. Besides, a single resonance within a wide rang of passband can be easily achieved. It is attractive especially in low frequency FSS design.