This article features a video on an FFT plot. It has been implemented in real-time, just by connecting and calibrating the blocks in the block-diagram. The video shows well how the FFT amplitude moves to the right, when the person approaches and to the left when the person moves away from the source.
If you want to learn more about the theory behind these FFT Plots, please read the in-depth article by our friend and co-author Eddie Hughes.
This feature is part of the package FreeScopes Basic II (3D-Scope, CFAR (2d), RCS, FFT (2d), Windows functions, Spectrogram, etc.). It builds on, and requires the basic set of features FreeScopes Basic I (A-Scopes, B-Scopes, STC, CFAR (1d), FFT (1d), IQ data blocks, MIT, etc.).