基于FPGA的数字锁相放大器设计与实现  

Digital Locked-in Amplifier Design Based on FPGA

作　　者：李硕 江晟 LI Shuo;JIANG Sheng

机构地区：[1]长春理工大学物理学院

出　　处：《计量与测试技术》2025年第1期83-85,89,共4页Metrology & Measurement Technique

摘　　要：在微弱信号检测中,锁相放大器具备较强的检测能力。为了能在其测量系统中集成锁相放大器,本文设计了一种基于FPGA的数字锁相放大器。使用模数转换器设计采集模拟待测信号的前置电路;基于DDS原理产生两路(10~10)kHz的正余弦参考信号;采用CIC与FIR级联设计低通滤波器;基于Qt实现上位机与FPGA的串口通信。结果表明:该锁相放大器具有小型化、抗噪声能力强、可实时处理等优点,可在测量系统中集成并测量微弱信号。In the weak signal detection,the phase-locked amplifier has a strong detection ability.In order to integrate a phase-locked amplifier in its measurement system,a digital phase-locked amplifier based on FPGA is designed in this paper.A/D converter is used to design the pre-circuit to collect and simulate the signal to be measured.Two(10 ~ 10) kHz sine and cosine reference signals are generated based on DDS principle.Low pass filter is designed by cascade of CIC and FIR.The communication between host computer and FPGA is realized based on Qt.The results show that the phase-locked amplifier has the advantages of miniaturization,strong anti-noise ability,real-time processing,etc.,and can be integrated and measured in the measurement system.

关 键 词：锁相放大器 FPGA 微弱信号检测 

分 类 号：TN722[电子电信—电路与系统] TN791