This document allows you to perform online Fourier filtering using an example of a signal consisting of two parts simulating pre-emergency and emergency modes. The pre-emergency mode is modeled by a sinusoidal signal, the emergency mode is modeled by a sinusoidal signal and an exponent. You can also perform online Fourier filtering for an arbitrary waveform from a waveform in the COMTRADE 1991 or 1999 format. You can see the essence of the Fourier transform here. Instructions for using the Fourier filter are given here.
Please choose source of signal:
Model signal
Oscillogram