基于磁性线圈和SAW谐振器的温测系统设计  

Design of Temperature Measurement System Based on Magnetic Coil and SAW Resonator

作　　者：刘晓群[1] 张琛昊 雷川 高博[2] LIU Xiaoqun;ZHANG Chenhao;LEI Chuan;GAO Bo(College of Engineering and Technology, Chengdu University of Technology, Leshan 614000,China;College of Physics, Sichuan University, Chengdu 610064,China)

机构地区：[1]成都理工大学工程技术学院,四川乐山614000 [2]四川大学物理学院,四川成都610064

出　　处：《压电与声光》2021年第2期165-169,共5页Piezoelectrics & Acoustooptics

基　　金：国家自然科学基金资助项目(81370350);成都理工大学校级课题基金资助项目(C122018027)。

摘　　要：利用2个带磁芯的磁性线圈天线和1个声表面波(SAW)谐振式传感器,开发了无线、无芯片地下传感器系统。首先,SAW由磁性天线的250 MHz交流电沿压电基片生成,其中,磁性线圈天线采用铜线圈绕制的大直径Ni0.8Fe0.2核心,利用传感器的叉指换能器,将通过传感器上的反射条返回的SAW能量转换为磁通量;然后,通过磁性天线发送至读取器,观察SAW传感器的中心频率随温度的变化,以进行实时温度监测。结果表明,在较大的读出距离下,该文提出的传感器系统对不同的地下温度变化、土壤类型具有鲁棒性。测得的敏感度为0.31 MHz/℃,线性度为0.95,具有较好的实用性。A wireless,chipless underground sensor system is developed by using two magnetic coil antennas with magnetic cores and one SAW resonant sensor.Firstly,SAW is generated by 250 MHz AC of magnetic antenna along piezoelectric substrate,in which,the magnetic coil antenna adopts a large diameter Ni0.8Fe0.2 core made of copper coil,and the SAW energy returned from the reflective strip on the sensor is converted into magnetic flux using the interdigital transducer of the sensor.Then,it is sent to the reader through the magnetic antenna to observe the change of the center frequency of SAW sensor with the temperature for real-time temperature monitoring.At a large readout distance,the proposed sensor system is robust to different underground temperature changes and soil types.The measured sensitivity is 0.31 MHz/℃,and the linearity is 0.95,which has good practicability.

关 键 词：压电基片 声表面波 传感器 读取器 温度监测 

分 类 号：TN65[电子电信—电路与系统] TP212[自动化与计算机技术—检测技术与自动化装置]