高性能微型RFID阅读器天线的设计与优化

Design and Optimization of High Performance Micro RFID Reader Antenna

为提高射频识别系统的应用范围和传输性能,设计了工作频率在13.56 MHz微型标签天线,该天线采用电感耦合方式进行信息传输,利用三维高频电磁仿真软件(High Frequency Structure Simulator,HFSS)设计出了微型射频识别天线的模型并进行了优化仿真,通过参数化扫描方式对天线的结构、介质板厚度、线间距以及线圈的匝数进行了可视化分析和比较,在模型的基础上完成了天线阻抗匹配。仿真结果表明,设计的微型天线在工作频率13.56 MHz时具有良好的辐射性能,其回波损耗值(S11)达到-58.18 dB,且天线的耦合性能优异,理论传输距离可达30 cm以上。对微型RFID阅读器天线的测试结果表明,该天线工作在13 MHz~15 MHz频段上时明显优于同环境、同类型的其他设计方案,实测回波损耗最小值达到-37 dB。其中在工作频率13.56 MHz时的回波损耗约为-27 dB。设计的微型标签天线在物流运输、图书管理以及可穿戴设备等方面具有广阔的应用前景。

In order to improve the application range and transmission performance of the RF identification system,a miniature tag antenna with an operating frequency of 13.56 MHz is designed,which adopts inductive coupling for information transmission,and a model of the miniature RF identification antenna is designed by using the 3D high frequency structure simulator(HFSS).The antenna structure,dielec⁃tric plate thickness,line spacing and number of turns of the coil are visualized and compared by parametric scanning,and the antenna im⁃pedance matching is completed on the basis of the model.The simulation results show that the designed miniature antenna has good radia⁃tion performance at the working frequency of 13.56 MHz,its return loss value(S11)reaches-58.18 dB.The antenna has excellent coupling performance,the theoretical transmission distance can reach more than 30 cm.The test results of the miniature RFID reader antenna show that the antenna is significantly better than other designs of the same type under the same environment when working on the 13 MHz-15 MHz frequency band.The measured return loss reaches-37 dB,and the return loss is about-27 dB at 13.56 MHz.The designed micro tag antenna has a broad application prospect in logistics and transportation,book management and wearable devices.