A Low-Profile Broadband Bandpass Frequency Selective Surface With Two Rapid Band Edges for 5G Near-Field Applications

• Published in: IEEE transactions on electromagnetic compatibility 2017-04, Vol.59 (2), p.670-676
• Main Authors: Li, Da, Li, Tian-Wu, Hao, Ran, Chen, Hong-Sheng, Yin, Wen-Yan, Yu, Hui-Chun, Li, Er-Ping
• Format: Article
• Language: English
• Subjects: 5G communication; 5G mobile communication; Bandpass; Bandwidths; Broadband; Circuits; Computer simulation; Electromagnetic interference; Equivalent circuits; Filtering theory; Frequency selective surfaces; Frequency selective surfaces (FSSs); Integrated circuit modeling; near-field electromagnetic interference (EMI); Shielding; shielding effectiveness; Substrates; Thin films
• ISSN: 0018-9375; 1558-187X
• DOI: 10.1109/TEMC.2016.2634279

A low-profile broadband bandpass frequency selective surface (FSS) with two rapid band edges is proposed in this paper for 5G near-field applications. The overall structure consists of three metallic layers, separated by two thin substrates with a thickness of 0.07λ. In addition, some centro-symmetric miniaturized slots are introduced in the middle metallic layer to further improve its stability and reduce its physical dimensions. A corresponding equivalent circuit model (ECM) is also proposed to better analyze the principles of the proposed FSS. Finally, an FSS prototype working at the center frequency of 27.5 GHz with a relative -3 dB bandwidth of 20.5% is fabricated and measured. More than 25 dB shielding effectiveness can be obtained out of the passband for a bandwidth of 1.46 GHz in this experiment. Both 3-D full-wave simulations and ECM results are in good agreement with the experimental results, having a maximum deviation of only 2.257% in the transmission zeros and poles. These results demonstrate that the proposed FSS is a good candidate for 5G near-field EMI shielding.