智能仪表PCB集成化RFID标签天线设计优化

Design and optimization of the tag antenna based on PCB integrated RFID in the smart meter

针对智能仪表信息追溯过程中,悬挂、贴附式射频识别(RFID)标签天线所带来的易脱落、性能下降等问题,提出一种智能仪表PCB集成化RFID标签天线。不同于传统RFID标签天线的附着方式,将标签天线直接蚀刻在智能仪表的PCB板上。为改善RFID标签天线性能,以智能电表作为研究对象,分析频点偏移与阻抗匹配劣化原因,根据理论指导确定标签天线优化方案并实验验证方案可行性;同时借鉴已有设计经验,进一步增强标签天线性能。设计优化结果表明,处于智能电表内的标签天线在860 MHz^960 MHz的工作频段内S11<-15 dB,阻抗匹配性能好;在920 MHz的频点上端口阻抗为16.87+j207.78Ω,增益达到2.71 dB,满足追溯过程中增益及方向性要求。

With regard to easy dropping and performance degradation caused by hanging and pasting radio frequency identification(RFID)tag antennas in the process of tracing information of the smart meter,a tag antenna based on printed circuit board(PCB)integrated RFID in smart meter was proposed.The tag antenna is directly etched on the PCB of the smart meter instead of traditional attachment method.In order to improve RFID tag antenna performance,the smart electric meter was used as research object,the reason of frequency offset and impedance match variation was analyzed,the tag antenna optimization was determined according to the theory and the feasibility of the scheme was verified by experiments;at the same time,the tag antenna performance was enhanced by existing design experience.The results of design and optimization show that S11 of the optimized tag antenna working in the smart electric meter is less than-15 dB in the working band of 860 MHz^960 MHz and impedance matching is excellent;the tag antenna operates in 920 MHz with port impedance of 16.87+j207.78Ω and the gain of 2.71 dB,which meets the gain and the directional requirements in the process of tracing information.