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.
- Spectral Estimation (Periodograms)
- Fast Convolutions (Fast Frequency Domain FIR Filters)
- Transform Coding (Used In STC, IRIDUM Vocoders, MPEGS, AC-3)
- Speech Recognition and Speech "Pitch" Modifications
- Speech and Image Enhancement (Spectral Noise Subtraction)
- Adaptive System Identification and Noise Cancellation
- Numerical Computation (solving systems of equations, finite elements, etc)
- 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.
The frequency difference between two adjacent bin centers or lines.
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.
- Further reading:
- Discrete-time Signal Processing, , US Imports & PHIPEs
- Fourier Transform and Its Applications, , McGraw-Hill Book Company Ltd
- Fast Fourier Transform and Its Applications, , Prentice-Hall
- Bruel & Kjaer - Technical Reviews These documents give detailed articles on measurement and signal processing theory.