基于数字锁相放大的时栅传感器信号处理研究  

Research of Signal Processing of Time Grating Displacement Sensor Based on Digital Lock-in Amplifier

作　　者：赵婷婷[1] 王先全[1] 姜增晖 王培懿[1] 文成杨[1] 王恋[1] 

机构地区：[1]重庆理工大学时栅传感及先进检测技术重庆市重点实验室

出　　处：《工具技术》2017年第4期87-92,共6页Tool Engineering

基　　金：国家自然科学基金(51275551)

摘　　要：针对时栅位移传感器对信号噪声和插补时钟频率稳定性敏感及需要时钟频率高的问题,提出了一种基于数字锁相放大技术的时栅位移传感器信号处理方法。该方法用STM32F4微处理器同步产生激励信号和采集时栅输出信号,不需采集正交参考信号,将正交参考信号和输出信号送入正交矢量型数字锁相放大器,实现角位移检测。研究了基于数字锁相放大技术的时栅传感器信号处理原理和算法,设计了A/D采集电路和窄带低通数字滤波器。仿真和试验表明:在信号噪声较大条件下,时栅位移传感器的误差控制在±1.1″以内,显著提高了精度。该方法只需采集一路感应信号即可实现传感器角位移检测,优化和简化了电路结构。Aiming at the problem that the grating displacement sensor is sensitive to signal noise and interpolation clock frequency stability and need frequency clock . This paper proposed a method of research of signal processing of time grating displacement sensor based on digital lock-in amplifier technology. The method using STM32F4 microprocessor syn- chronous generates excitation signal and collects output signal of time grating without collecting orthogonal reference signal. The orthogonal reference signal and the output signal into the orthogonal vector digital lock-in amplifier to complete angular displacement detection. Research signal processing theory and algorithms of time grating displacement sensor based on digit~ al lock-in amplifier, design of A/D sampling circuit and narrow band low-pass digital filter. The simulation and experimental results show that：the error of the time displacement can be up to ±1.1＂ under noisy signal conditions, significantly im- proved the accuracy. In addition,this method only collects a way sensing signal to realize angular displacement detection of time grating sensor, optimizing and simplifying the circuit structure.

关 键 词：数字锁相放大器 STM32F4 DDS A/D转换 时栅 信号处理 

分 类 号：TG839[金属学及工艺—公差测量技术] TH822[机械工程—仪器科学与技术]