相敏检波技术测量微弱信号的原理与方法

TO MEASURE SMALL SIGNAL BY THE TECHNIQUE OF THE COHERENT DETECTION

介绍用相敏检波技术测量直流微弱信号的方法,并在理论上作了较为详细的分析。实验结果表明:其检测灵敏度可达0.5μV,测试精度优于±0.5％。

This paper introduces a kind of technique to measure small direct signal voltage by the coherent detection amplifier, and briefly analyses the measure principle. The experiment results show that the sensitivity is 0. 5 uV, and the accuracy is better than +0. 5%.