To summarize, zero-padding is used for
- padding out to the next higher power of 2 so a Cooley-Tukey FFT can be used with any window length,
- improving the quality of spectral displays, and
- oversampling spectral peaks so that some simple final interpolation will be accurate.
Some examples of interpolated spectral display by means of zero-padding may be seen in §3.4.
Kaiser Window Beta Parameter
Index Ranges for Zero-Phase Zero-Padding