Increase in the accuracy of evaluating spectra of discrete signal realization

An improved algorithm for calculating spectra with the use of a rapid Fourier transform and quadrature equations of the trapezium and Simpson’s methods is considered. The relative error of calculation by comparing the relative deviation of a continuous spectrum of final realization of the signal from spectra, found by means of improved algorithms at a discrete set of frequencies, is analyzed. A more precise initial estimation of a spectrum is obtained using the improved calculation algorithms. __________ Translated from Metrologiya, No. 8. pp. 27–31, August, 2007.