TECHNIQUE OF SPECTRAL ANALYSIS OF PERIODIC MULTIFREQUENCY SIGNALS Russian patent published in 2004 - IPC

FIELD: measurement technology, information processing systems, determination of spectral composition of periodic signal. SUBSTANCE: reference sinusoidal signal b₀(t_j) shifted many times by phase with reference to analyzed periodic multifrequency signal a(t_j) is formed in compliance with invention. Both signals are presented in the form of readings of momentary values for same time moments t_j = t₁,t₂,...,t_N, where N is number of divisions in period T. Then points a(b₀) of joint decision under various angular frequencies ω₀ of reference signal and phases ϕ₀ of reference signal are found, volt-ampere characteristics are constructed and their area F_BAXmin is established. Conclusion on presence of harmonic component with angular frequency ω_K and phase ϕ_K in analyzed signal a(t_j) is drawn proceeding from condition F_BAX = 0. Thereafter maximal area of volt-ampere characteristic F_BAXmaxK with ϕ_K±90^° is determined and amplitude of K-th spectral component is found by formula and judgment on spectral composition of analyzed signal a(t_j). is made by values ω_K,ϕ_K and A_mk. EFFECT: improved efficiency of determination of spectral composition of periodic multifrequency signal carrying components of any frequency. 1 dwg, 1 tbl