A 2 b Dual-Band Multifunction Frequency Selective Surface

A novel 2 b dual-band multifunction active frequency selective surface is proposed. The frequency response of the surface is guided by four binary states controlled via direct current supply biasing of two p-i-n diodes. The binary combination states 00 and 11 offer transmission at center frequencies of 2.3 and 5 GHz and shield to bands at 5 and 2.3 GHz for transverse electric/transverse magnetic modes, respectively. The related fractional bandwidths of the lower and upper frequency bands are 127\% and 75\% with insertion losses of 0.5 and 0.2 dB, respectively. The binary state 10 offers transmission at 2.3 GHz frequency and shields to the passbands at 5 GHz frequency when the incident-plane wave is transverse electric (TE)-polarized. The binary state 01 allows transmission at 5 GHz frequency and shields to the passband at 2.3 GHz frequency when the incident plane wave is transverse magnetic (TM)-polarized. The design of the structure is flexible to electromagnetic switching and polarization selection for the two bands with the advantage of low insertion loss in the passbands. The prototype of the structure is fabricated and measured, transmission response at all binary states concurs well with the full-wave simulated transmission response.