Dual-Band High Selective Frequency Selective Surface Design and Analysis

Abstract

In this paper, a second-order, dual-band, band-pass frequency selective surface (FSS) with high selectivity is presented by cascading three-layers of periodic metallic arrays. The unit cell in both two exterior layers is composed of gridded-double square loops (G-DSLs) while the element in the middle layer is consisting of wire grid. The three layers are separated by two thin F4B-2 substrates with dielectric constant of 2.65 + 0.02i. The proposed FSS can provide multi-transmission poles and multi-transmission zeros. There are two transmission poles in each pass-band. The two pass-bands are separated by two transmission zeros. On the upper side of the second pass-band, other two transmission zeros are generated also. These transmission zeros lead to a wide out of band rejection and a fast fall off response on both sides of each pass-band. The simulation is implemented using full wave electromagnetic simulator CST Microwave Studio, the central frequencies of the two pass-bands are 12.7 and 17.4 GHz. In addition, the designed principle is described using equivalent circuit model (ECM). Furthermore, the prototype of the FSS is fabricated and measured. Both simulated and measured results demonstrated that the proposed FSS has the merits of incident angle stability from 0° to 60° for both TE and TM polarizations.