A novel FSS structure with high selectivity and excellent angular stability for 5G communication radome

A novel frequency selective surface structure (FSSs) with high selectivity and excellent angular stability is proposed in this paper. To improve the performance of the FSS especially in angular stability, the coupling of capacitive surface and inductive surface is employed to realize the miniaturization of the structural unit around 0.23λ. Furthermore, to enhance the passband of the FSS, a multi-layer FSS structure is adopted to form a 2nd-order filter. In addition, as a bandstop with a high suppression is demanded in the 5G communication, we introduce a “Jerusalem cross“ structure in the inductive surface layer ingeniously to add the LC series resonance which can realize a rapid decline in the passband edge. One significant feature of this FSS design is that the passband and stopband can be controlled by different parts of the structure respectively, which greatly improves the FSS stability. Finally, a novel FSS working at the center frequency of 28.5 GHz with a low-profile broadband and a high rejection stopband is designed. It still has a stable transmission performance, when the incident wave angle changes up to 60°. These results demonstrate that the proposed FSS is a good candidate for 5G communication radome.