小信号幅度测量中的差分同步解调技术

A differential synchronous demodulation technique for small-signal amplitude measurement

本文介绍一种用于测量小信号幅度的电路 ,被测信号范围为微伏级到几毫伏。电路设计方法适用于将数模混合型正弦波发生器作为信号源的测量仪器。文中主要讨论两方面问题 。

This paper presents a circuit for measuring the amplitude of small signals in a range from microvolts to some dozens of millivolts.The design method of the circuit is applicable to some measuring instruments where a hybrid D/A sinewave generator is used as a signal source.The paper is focused on two points for discussion,i.e. the accurate demodulation of the difference of two sinewave signals and the common mode correction of meassurement.