METHOD DETERMINING SPECTRUM OF ELECTRIC SIGNALS Russian patent published in 1999 - IPC

FIELD: measurement technology, spectral analysis of electric signals. SUBSTANCE: method determining spectrum of electric signal y(t) lies in generation of digital reading y[k] of signal after equal time intervals Δt, in formation of interpolating functions between neighboring readings of signal, in determination of approximation function approximating signal and in finding of Fourier image of this function, in making function of signal y(t) of type of in which interpolation time function presents polynomial 0≤t<Δt in first discretization interval , in next interval it is presented by difference of polynomials interpolating analyzed and preceding sections of function of signal as , , , where a_k,i is sum of weight coefficients at tⁱ. In last discretization interval linear polynomial is used after which spectral coefficients are computed by formula . EFFECT: higher accuracy in determination of spectrum and wider region of working frequencies. 2 dwg