A 2.5D Miniaturized Wide Passband Frequency Selective Surface with High Selectivity

A novel 2.5D miniaturized wide passband FSS is proposed in this paper. Compared with planar FSS, the 2.5D FSS structure can realize double sideband sharp roll off characteristic. Different middle substrate and thickness is chosen to improve impedance matching. More important, L-shaped stubs and miniaturized unit size can achieve angular stability. The proposed wide passband FSS structure is simulated and the results are analyzed. The results show that the structure can have a transmission passband of 7 to 15.8 GHz and the insertion loss is less than 1 dB. The transmission efficiency can achieve 80% to 95% over the operating bandwidth. The FSS filter has good polarization stability and low sensitivity in response to oblique incident angles.