变形工作状态下非等间距柔性NFC标签天线设计  

Design of non-equal spacing flexible NFC tag antenna under deformed working states

作　　者：孙英[1,2] 花赛月 刘乃源 周严[3] 翁玲[1,2] Sun Ying;Hua Saiyue;Liu Naiyuan;Zhou Yan;Weng Ling(Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province,Hebei University of Technology,Tianjin 300130,China;State Key Laboratory of Reliability and Intelligence of Electrical Equipment,Hebei University of Technology,Tianjin 300130,China;College of Science,Tianjin University of Commerce,Tianjin 300134,China)

机构地区：[1]河北工业大学河北省电磁场与电器可靠性重点实验室,天津300130 [2]河北工业大学省部共建电工装备可靠性与智能化国家重点实验室,天津300130 [3]天津商业大学理学院,天津300134

出　　处：《电子测量与仪器学报》2022年第5期57-66,共10页Journal of Electronic Measurement and Instrumentation

基　　金：国家自然科学基金项目(52077052)资助。

摘　　要：柔性NFC标签天线常处于变形工作状态,为解决该工作状态下易出现的频率偏移及偏移引起的工作性能下降问题,提高其在人体无线健康监测应用领域的适用性,本文设计了一款可贴合人体皮肤且性能优良的柔性NFC标签天线。该天线采用镓铟液态金属作为柔性导电材料,与PDMS柔性衬底材料相结合,使其具有良好的可拉伸性和可弯曲性;基于小型化NFC天线设计的原则,提出非等间距结构设计方案,提高其工作带宽,实现NFC标签天线在变形工作状态下依然保持相对稳定的电学参数、谐振频率及通信距离,增强其工作稳定性。通过仿真和实验测试结果表明,外形尺寸为25 mm×25 mm且线间距增长率为200%的非等间距NFC标签天线,在-10 dB以下工作带宽高达0.87 MHz,相较于具有相同面积的等间距天线,工作带宽最大增幅高达52.6%;针对此柔性NFC标签天线应用环境的特殊性,通过不同变形状态下的工作性能稳定性测试显示,30%拉伸工作状态时,天线的中心频率偏移率仅为3.2%;曲率半径为5 mm的弯曲工作状态时,天线的中心频率偏移率仅为2.4%,天线通信距离始终不低于30 mm,在变形工作状态下总体表现出良好的工作稳定性。Since the flexible NFC tag antenna is usually in a deformed working state,in order to solve the problem of frequency offset and the performance degradation caused by the frequency offset in this working state,and to improve its applicability in the application of wireless human health monitoring,a flexible NFC tag antenna with human skin adaptation and excellent performance is designed.The antenna uses gallium indium liquid metal as a flexible conductive material,combined with PDMS flexible substrate material to enhance the stretchability and flexibility of the NFC tag antenna.Based on the principle of miniaturized NFC antenna design,this paper proposes a novel non-equal spacing structural design scheme to increase the working bandwidth of the antenna,maintain relatively stable electrical parameters,resonant frequency as well as communication distance under different deformed states and improve the working stability.The simulation and experimental results show that the working bandwidth below-10 dB of the non-equal spacing NFC tag antenna with an external size of 25 mm×25 mm and a line spacing growth rate of 200% can reach 0.87 MHz.Compared with an equal line spacing antenna with the same area,the maximum increase in working bandwidth is up to 52.6%.Aiming to the particularity of the application environment of this flexible NFC tag antenna,in the stretching working state with a stretching degree of 30% and the bending working state with a curvature radius of 5 mm,the center frequency deviation of the antenna is 3.2% and 2.4%.The antenna communication distance is always no less than 30 mm,and it shows good working stability under deformed working states.

关 键 词：柔性NFC天线 变形工作状态 镓铟合金液态金属 非等间距 

分 类 号：TP202[自动化与计算机技术—检测技术与自动化装置] TH82[自动化与计算机技术—控制科学与工程]