摘要
基于FPGA研制了一种用于微弱信号检测的便携式正交锁相放大器。先由信号处理模块接收待测信号并对其进行可变增益放大与工频噪声滤波,经过A/D转换模块转换后输入FPGA,通过数字锁相环完成对待测信号的相位锁定,提取反馈信号以计算待测信号幅度,实现微弱信号检测。该锁相放大器的幅度测量范围为100 nV^100μV、动态范围达60 dB,相位精度达0.001°。该系统设计为便携式设备,成本低,易维护,可满足野外作业等特殊环境的测量要求,具有广阔的应用前景。
A portable orthogonal phase-locked amplifier for weak signal detection has been developed based on FPGA.First,the signal processing module receives the signal,does variable gain amplification on the signal and puts it through the power frequency noise filtering.The signal is put into the FPGA through A/D conversion module conversion.By the digital phase-locked loop,the amplifier completes the measured signal phase lock,extracts the feedback signal to calculate the measured signal amplitude,and completes weak signal detection.The lock-in amplifier amplitude measurement range is 100 nV^100μV,dynamic range can reach up to 60 dB,phase accuracy can attain 0.001°.The system is designed as a portable device,low cost,easy to maintain,can meet the measurement requirements of the special environment such as fieldwork or etc,and has broad application prospects.
作者
谢桂辉
郑旭初
赵天明
刘子绪
赵娟
Xie Guihui;Zheng Xuchu;Zhao Tianming;Liu Zixu;Zhao Juan(School of Automation,China University of Geosciences,Wuhan 430074,China;Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems,Wuhan 430074,China;School of Mechanical and Electronic Information,China University of Geosciences,Wuhan 430074,China)
出处
《电子技术应用》
2018年第10期78-82,87,共6页
Application of Electronic Technique
作者简介
谢桂辉(1988-),男,博士,讲师,主要研究方向:电路系统设计、FPGA开发;郑旭初(1996-),男,本科,主要研究方向:PCB布局布线;赵天明(1996-),男,本科,主要研究方向:嵌入式程序设计。
