A method for accurate estimation of the low frequency and the Fourier spectrum angle for real time analysis of dynamic systems

摘要

A method for estimating a low frequency and a spectrum phase for a real-time analysis of a dynamic system is provided to accurately estimate the low frequency and a phase of a Fourier spectrum by fitting a peak value and a left/right spectrum calculated in discrete Fourier transformation with an exponential attenuation function. A peak frequency and a peak value of a low frequency band for analyzing the dynamic system is calculated from the Fourier spectrum(S130). The frequency and the left/right spectrum of the Fourier transformation are selected by corresponding to the peak value(S140). The selected spectrum is fitted by using the exponential attenuation function(S160). The peak value is selected from the fitted spectrum. A frequency corresponding to the peak value is selected as the accurate frequency and the spectrum phase corresponding to the accurate frequency is selected as the accurate phase(S170). A selection result is stored and outputted(S180).