REVISED FAST FOURIER TRANSFORM
DOI:
https://doi.org/10.15588/1607-3274-2015-1-9Keywords:
digital signal processing, discrete Fourier transform, fast Fourier transformAbstract
The problem of realisation of the Discrete Fourier Transform in on-line is analysed because of non-efficient consuming a time for a newrecalculation of spectrum samples if one discrete-time signal sample or even some small portion of samples in period are replaced by new
sample or by new samples, respectively. Using Fast Fourier Transform (FFT) procedure it is assumed that some signal samples in the respective period available for processing digitally are updated by a sensor in real time. It is urgent for every new sample that emerges to have a new spectrum. The ordinary recalculation of spectrum samples even with highly efficient Cooley-Tukey FFT algorithm is not suitable due to speedy varying in time real process to be observed. The idea is that FFT procedure should not be recalculated with every new sample, it is needed just to modify it when the new sample emerges and replaces the old one. We retrieve the recursive formulas for FFT algorithms that refer to the spectrum samples modification. In a case of appearing one new sample, the recursive algorithm calculates a new spectrum samples by simple addition of a residual between an old and new samples, multiplied on respective row of Fourier ‘code’ matrix, to a vector of old spectrum samples. An example of 8-point FFT is presented.
References
Deziel J. P. Applied introduction to digital signal processing / J. P. Deziel. – New Jersey : Prentice Hall, Inc., 2000. – 388 p. 2. Gonzalez R. C. Digitale Image Processing / R. C. Gonzalez. – New Jersey : Prentice Hall, Inc., 2007. – 976 p. 3. Oppenheim A. V. Discrete-time signal processing / A. V. Oppenheim, R. W. Shafer. – New Jersey : Prentice Hall, Inc., 2009. – 1120 p. 4. Proakis J. G. Digital signal processing. Principles, algorithms, and applications / J. G. Proakis, D. G. Manolakis. – New Jersey : Prentice Hall, Inc., 2006. – 1004 p. 5. Proakis J. G. Student manual for digital signal processing with Matlab / J. G. Proakis, V.K. Ingle. – New Jersey : Prentice Hall, Inc., 2006. – 264 p. 6. Lyons R. G. Understanding digital signal processing / R. G. Lyons. – New Jersey : Prentice Hall, Inc., 2010. – 984 p. 7. Richardson M. H. Fundamentals of the discrete Fourier transform / M. H. Richardson // Sound & Vibration Magazine. – 1978. – March. – P. 1–8. 8. Smith S. W. Digital signal processing. A practical guide for engineers and scientists / S.W. Smith. – San Diego : California Technical Publishing, 2003. – 640 p. 9. Pupeikis R. Vaizdu apdorojimo Matlab’o terpėje pagrindai / R. Pupeikis. – Vilnius : Technika, 2008. – 107 p. 10. Pupeikis R. Self-tuning minimum variance control of linear systems followed by saturation nonlinearities in a noisy frame / R. Pupeikis / / International Journal of Robust and Nonlinear Control. – 2014. – Vol. 24, № 2. – P. 313–325. DOI: 10.1002/rnc.2888 11. Казлаускас К. Цифровые системы обработки данных. Монография./ К. Казлаускас, Р. Пупейкис. – Вильнюс : Мокслас, 1991. – 220 с. 12. Cooley J. W. An algorithm for the machine calculation of complex Fourier series/ J. W. Cooley, J. Tuke // Mathematics Computation. – 1965. – Vol. 19 – P. 297–301. 13. Brigham E. Fast Fourier transform and its applications / E. Brigham. – New Jersey : Prentice Hall, Inc., 1988. – 446 p.
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