GMM和SAW谐振器复合磁传感器设计与分析

Design and Analysis of Composite Magnetic Sensor Consisting of GMM and SAW Resonator

提出了一种新的超磁致伸缩材料(GMM)和声表面波(SAW)谐振器构成的复合磁传感器,将磁场中GMM的应力应变传递到SAW谐振器上,改变其谐振频率,检测谐振频率进行磁场测量。推导了复合磁传感器在磁场中的频率响应及磁场-频率偏移量关系,并对传感器的静态特性进行了测试。分析表明该传感器为低通系统,截止频率约为14.34Hz。实验验证了复合传感器的最高静态灵敏度可达到190Hz/Oe。

A new composite magnetic sensor using giant magnetostrictive material（GMM） and surface acoustic wave（SAW） resonator was presented with theoretical derivation, numerical calculation and experimental validation. The stress and the strain of giant magnetostrictive material induced by magnetic field were transferred to surface acoustic wave resonator and the resonant frequency of resonator varied. Magnetic field strength can be measured through the detection of resonant frequency. Theoretical derivations prove that the magnetic sensor is a low-pass system, with the cut-off frequency of 14. 34 Hz in terms of off-the-shelf device parameters. Experimental results indicate that the static sensitivity of the sensor can reach 190 Hz/Oe.