Digital Lock-In Detector for Ultra-Low Level Noise Spectrum Analysis

摘要

A personal computer based digital lock-in detector was developed and used in ultra-low level noise spectrum analysis. The digital lock-in detector was integrated with a digital spectrum analyzer based on an Apple IIe computer to form a complete noise spectrum analysis system. This system is capable of analyzing noise signals much lower than internal amplifier noise. Keywords: Noise measurements, Digital lock in detector, 1/f noise, Microcomputers.