An introduction to FFT and time domian windows

In order to tackle fast Fourier transform (FFT) and time domain windows, a brief tutorial on digital spectrum analysis and FFT-related issues to form special estimates on digitized signals has been discussed. The discussion is intended to give the basic elements of FFT-based spectrum analysis, starting with the properties of the DFT and introducing considerations related to its fast implementation. The default window, the rectangle and its contribution to spectral leakage, as well as designed windows and how they can be used to obtain accurate spectral estimates has been examined as well. The main properties of the windows used in spectrum and network measurements along with information on their secondary attributes has been compared and discussed.