fast Fourier transform (FFT) An algorithm (e.g. the Cooley—Tukey method) which enables the Fourier transformation of digitized wave-forms to be accomplished more rapidly by computer than would be possible using direct evaluation of the Fourier integral. FFT usually involves iterative techniques. See also FOURIER ANALYSIS; and FOURIER TRANSFORM.

fast Fourier transform (FFT) An algorithm that computes the discrete Fourier transform accurately and efficiently on digital computers. FFT techniques have wide applicability in linear systems, optics, probability theory, quantum physics, antennas, and signal analysis.