A Bandpass Frequency Selective Surface Using Ring Slots for Dual-Band Applications

A Frequency Selective Surface (FSS) with dual-band bandpass response at 2.4 GHz and 5.2 GHz is proposed in this paper. The proposed FSS unit cell consists of two circular ring slots loaded with metallic splits for the purpose of fine tuning of the transmission poles. The FSS exhibits −3 dB bandwidths of 0.68 GHz and 0.63 GHz in the first and second passbands respectively. The FSS exhibits lower insertion loss of around 0.25 dB in both the passbands. A detail study of effect of the split gap on the response of the dual-band FSS is also presented in the paper. The FSS is suitable for various applications in the ISM band.