Discrete fast Fourier transform (FFT) has been widely applied to signal spectral analysis and can figure out the entire bandwidth spectrum of a signal.

The identification of plant samples using Fourier transform infrared spectrometer with OMNI collector is simple, convenient, fast and accurate.

The power spectra curve as a function of the mode number of outer or inner profiles are also calculated by the application of fast Fourier transform to the circumferential profile data.