SAW应变测量中谐振频率提取技术研究  

Research on resonant frequency measurement in SAW strain sensing

作　　者：陈磊[1] 徐春广[1] 周世圆[1] 肖定国[1] 

机构地区：[1]北京理工大学机械与车辆工程学院,北京100081

出　　处：《传感器与微系统》2009年第2期32-34,共3页Transducer and Microsystem Technologies

摘　　要：声表面波(SAW)应变测量中,所要处理的回波信号具有瞬时、中频、窄带的特点,传统的傅立叶变换(FFT)频谱分析法的频率分辨率受信号采样长度的制约,无法满足SAW应变测量的精度要求。通过对SAW谐振器工作原理的分析,采用基于数字下变频技术测量回波信号频率,仿真验证和对实测信号的测量证明了该测量方法的可行性与有效性。The echo signals in SAW strain sensing have characteristics of instantness,intermediate frequency and narrowband. The frequency resolution of the tradition FFT analytical method is restricted by signal sampling length. The resolution can＇ t fit precision in SAW strain sensing. Through analyzing the theory of SAW resonator, digital down conversion is used to mearsure the frequency of echo signal. The feasibility and validity of the method is proved by simulation and experiment.

关 键 词：数字下变频 应变测量 谐振频率测量 MATLAB仿真 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]