吉林大学学报（信息科学版）2012，Vol.30Issue(1)：5-11,7.
基于自动频率跟踪的虚拟数字锁相放大器
Virtual Digital Lock-in Amplifier Based on Automatic Frequency Tracking
摘要
Abstract
In order to avoid the crosstalk between the measured signal and the reference signal, and the noise introduced during the transmission of the signal in traditional design, a virtual (DLIA: Digital Lock-In Amplifier) based on Lab VIEW platform is designed. An automatic frequency tracking module is used in this design, and the mismatch between the frequencies of the measured signal and the reference signal is greatly reduced. By optimizing the output signal, an excellent waveform was observed, based on the traditional quadrature phase sensitive detection algorithm. The experimental results show that the SNR(Signal to Noise Ratio) of the measured signal is less than - 20 dB, the minimum detectable amplitude is up to 10 μV, and the relative error of the frequency-locking by the automatic frequency tracking module and that of the measured signal's amplitude are less than 0. 02% and 0. 05%, respectively. That there is good measuring stability of the designed virtual DLIA with automatic frequency tracking module.关键词
信号检测/数字锁相放大器/自动频率跟踪/虚拟仪器Key words
signal detection/ digital lock-in amplifier (DLIA)/ automatic frequency tracking/ virtual instrument分类
信息技术与安全科学引用本文复制引用
赵玲,田小建,梁磊,郑传涛,王一丁..基于自动频率跟踪的虚拟数字锁相放大器[J].吉林大学学报（信息科学版）,2012,30(1):5-11,7.基金项目
国家高技术研究发展计划(863计划)基金资助项目(2009AA032442) （863计划）
