Digital Lock-in Amplifier Based on Microcontroller  

作　　者：陶安利 徐国栋 骆科学 张钢领 

机构地区：[1]Shandong University of Science and Technology,College of Information and Electrical Engineering

出　　处：《Journal of Measurement Science and Instrumentation》2010年第3期285-288,共4页测试科学与仪器（英文版）

摘　　要：A method of implementing high cost-effective and highly integrated digital lock-in amplifier with microcontroller is discussed. And the digital lock-in amplifier is more suitable for meastwing lowfrequency weak signal. Digital signal sequence is obtained through sampling signal measured over an integer number of signal periods, but digital reference sequence is acquired through mathematical operation, then digital phase sensitive detection can be implemented by calculating the cross-correlation function of digital signal sequence and digital reference sequence. In addition, the frequency response and phase character of the digital lock-in amplifier is analyzed. Finally, the designed digital lock-in amplifier is achieved. Expermental results show that the digital lock-in amplifier can be used for measuring weak signal with low ignal-to-noise ratio.

关 键 词：digital lock-in amplifier SNR MICROCONTROLLER 

分 类 号：TN722[电子电信—电路与系统]