弱信号锁相放大CD552-R3电路  

CD552-R3 Lock-in Amplifier Circuit for Weak Signal

作　　者：何明霞[1] 曲秋红[1] 李萌[1] 王文霞[1] 

机构地区：[1]天津大学精密仪器与光电子工程学院,天津大学太赫兹波中心,天津300072

出　　处：《传感技术学报》2010年第10期1454-1457,共4页Chinese Journal of Sensors and Actuators

基　　金：国家自然基金资助项目(60977064);天津市科技支撑计划重点项目资助(09ZCKFGX01500);天津市应用基础项目资助(10JCYBJC01400)

摘　　要：锁相放大电路是微弱信号检测的重要方法。基于CD552-R3相敏检波芯片设计了一种锁相放大电路,应用于大背景噪声下微弱信号的检测。采用信号发生器产生的标准信号和染噪信号,对该锁相放大电路进行了鉴幅和鉴相性能测试,并在不同强度噪声下对弱信号进行检测。测试结果表明:研制的锁相放大电路输出线性度高于0.9999,具有良好的鉴幅和鉴相特性,能将信噪比为-36dB的毫伏级信号提取出来,可用于大背景噪声下微弱信号的检测。Lock-in amplifier（LIA）technique is one of important metheds for weak signal detection.A novel LIA circuit based on CD552-R3 phase sensitive detector is designed for the weak signal detection under strong background noise.The performance test on amplitude discrimination,phase discrimination and signal detection under noise of different levels has been completed with standard and noise-mixed signals given by Multifunction Signal Generator.The result shows that the CD552-R3 LIA circuit has good performance amplitude discrimination and phase discrimination.Its linearity input-output is above 0.9999,it can obtain Millivolt level signals under strong background noise,and the signal noise ratio reaches-36 dB.It means the LIA circuit can get weak signal under a noise background easily.

关 键 词：噪声 弱信号 相敏检波 锁相放大 CD552-R3 

分 类 号：TP271[自动化与计算机技术—检测技术与自动化装置]