基于数字锁相放大器的电阻噪声特性研究  

Resistance noise characteristics based on digital lock-in amplifier

作　　者：郑远 姚星星 郭红丽 鲍德松[1] 王业伍[1] ZHENG Yuan;YAO Xing-xing;GUO Hong-li;BAO De-song;WANG Ye-wu(Teaching Center for Physics, Department of Physics, Zhejiang University, Hangzhou 310025, China)

机构地区：[1]浙江大学物理学系物理实验教学中心,浙江杭州310025

出　　处：《物理实验》2021年第10期11-18,共8页Physics Experimentation

基　　金：浙江大学实验技术研究项目(No.SJS202001);浙江省高校实验室工作研究项目(No.YB202135);浙江大学本科教学研究项目(No.zdjg21042)。

摘　　要：基于SR830型锁相放大器,设计了以LabVIEW软件实时通信测量的电阻噪声特性研究实验,验证了热噪声与闪烁噪声的主要特征,评估了实验系统的本底噪声,并从信噪比特点分析了适合测定散弹噪声的实验条件,提供了降低电阻噪声的方法.结合RC低通滤波原理对1~4阶低通滤波器的滤波带宽、带边斜率和阶跃响应等特性做了分析,讨论了2种调节动态储备的方法.通过电阻噪声实验探究了时间常量、陡降和动态储备对测量噪声的影响,提供了优化测量参量的思路.Based on the SR830 lock-in amplifier,the resistance noise experiment measured by LabVIEW software real-time communication was designed.The main characteristics of thermal noise and scintillation noise were verified,and the background noise of the measurement system was evaluated.Based on the characteristics of signal-to-noise ratio,the experimental conditions suitable for measuring shot noise were analyzed,and a method to reduce resistance noise was provided.Combined with the RC low-pass filter principle,the characteristics of the filter bandwidth,bandedge slope and step response of the 1~4th order low-pass filter were analyzed,and two methods of adjusting dynamic reserve were discussed.Through the resistance noise experiment,the influence of time constant,roll-off and dynamic reserve on the measurement noise was explored,and the idea of optimizing the measurement parameters was provided.

关 键 词：锁相放大 电阻噪声 时间常量 陡降 动态储备 LABVIEW 

分 类 号：TN722[电子电信—电路与系统]