Abstract
We have previously developed an Alternating Noise Canceling (ANC) method that can reduce normal mode noise and equi-status noise, but parameter design and working principle are not sufficiently clear. In this paper, we have clarified the method of parameter design and working principle of ANC. The parameters of ANC method in application for instrumentation are switching frequency and cutoff frequency of low pass filter. Then these parameters are determined using a maximum frequency of transmitting signals and a maximum frequency of noises in transmission line. The working principle can be clear by interpreting ANC method as an amplitude modulation by a square-carrier wave and by applying frequency-domain analysis for modulated waves.
