Fast Fourier Transform

An algorithm, or digital calculation routine, that efficiently calculates the discrete Fourier transform from the sampled time waveform. In other words it converts, or "transforms" a signal from the time domain into the frequency domain.


Historical Notes

  1. 1965 Tukey and Cooley publish a paper introducing the "Fast Fourier Transform" algorithm.


The individual frequencies at which the amplitudes are calculated, commonly called lines.

Line Spacing

The frequency difference between two adjacent bin centers or lines.

Narrowband Analysis

Another way of saying FFT analysis.


An amplitude weighting of the time signal used with gated continuous signals to give them a slow onset and cut-off in order to reduce the generation of side lobes in their frequency spectrum.

See also: Blackman Window, Bohman Window, Cauchy Window, Discrete Fourier Transform, FFT Analyser, Fourier Transform, Hamming Window, Hanning Window, Kaiser Bessel Window, Leakage, Overlap Processing, Picket Fence Effect, Rectangular Window, Signals, Windowing.

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Subjects: Analysis Mechanical Engineering Noise & Vibration Physics Signal Processing

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