A R-T-R FSS Structure with Dual-Polarization and High Selectivity in C-Band and X-Band for Radome

A frequency selective surface structure with dual-polarization and high selectivity in C-band and X-band is proposed in this paper. The unit of the structure is cascaded by a layer of double square loop(DSL) structure and a layer of gridded square loop(GSL) structure. The simulation results show that the double-layer structure can generate a reflection-transmission-reflection(R-T-R) type FSS with intermediate passband and two side stopbands. The center frequency of the passband is 6.5GHz and the bandwidth is 1GHz. The stopband on the left is 4GHz-5GHz while the stopband on the right is 8GHz-12GHz. The bandwidth of the transition band between the two stopbands and the passband is about 0.9GHz and 0.7GHz. It has a stable performance when the angle of the incident wave varies from 0° to 40° with both TE and TM polarization from simulation results.