An X-band and Ku-band adjustable polarization insensitive AFSS reflector

In this paper, an adjustable active frequency selective surface (AFSS) with polarization insensitive properties is proposed. The designed structure comprises an active impedance layer, a dielectric layer, and a metal backplane layer. The active impedance layer contains “” - shaped structural unit, whose modulating properties are realized by controlling pin diodes. The switchable bandwidth of the proposed structure can achieve an adjustable effect of less than −15dB and covers a much wider frequency band (8.8-11.8GHz and 12.6GHz-18.6GHz) compared with previous adjustable AFSS reflector. Meanwhile, the structure is suitable for the two polarization states of TE and TM due to the symmetry of the unit structure. Finally, the CST simulation is carried out to demonstrate the validation of proposed structure.