A 4-Bit higher Order Tri-Band FSS With Multifunction Property at Two Bands

This research introduces a tri-band frequency selective surface with multifunction performance at two bands. Nine different functional states are achieved with biasing to the four pin diodes. Two closely spaced bands around 2 GHz and 4 GHz furnish shift in electromagnetic behavior and inversion to plane wave polarization. The binary state "0000" contributes transmission to the dual polarized plane wave for both polarizations at pass band of 2 GHz as central frequency and shielding to the wave at pass band around 4 GHz. Conversely, the binary state "1111" contributes inverse electromagnetic behavior at these bands. The binary state "1010" contributes transmission to the TE wave at 2 GHz frequency and furnishes shielding to the 4 GHz band, whereas the binary state "0101 contributes transmission to the TM wave at 4 GHz frequency with shielding at 2 GHz. The binary state "1101 = 1110" allows to transmit the band around 4 GHz for TE wave, whereas the binary state "1011 = 0111" contributes shielding to the two multi-functional bands around 2 GHz and 4 GHz frequencies. The binary state "1011 = 0111" is inversion of the "1101 = 1110" state. The binary state "1000 = 0100" allows to transmit the band around 2 GHz for TE wave, whereas the binary state "0001 = 0010" contributes shielding to the two multi-functional bands around 2 GHz and 4 GHz frequencies. Converse is true for the binary state "0001 = 0010". The binary state "0011" = "1100" shields both the bands at 2 GHz and 4 GHz frequencies for dual polarized plane wave. All the binary states which contributes a pass band at 2 GHz also add an extra pass band around 5.9 GHz which is angularly stable at TE wave excitation only.