An windowed frequency domain interpolation algorithms for damped sinusoidal signals

Abstract

An algorithm for the estimation of parameters that characterize a multi-frequency damped sinusoidal signal is presented. At first, the signal is weighted by using the Hanning window before the fast Fourier transform (FFT), then the frequencies, amplitudes, phases and damped factors of the signal are obtained by frequency domain interpolation. It is shown that the purpose of improving the accuracy of parameter estimation is achieved by using the Hanning window which reduces the long-range leakage and by frequency domain interpolation which eliminates the short-range leakage. The sensitivity analysis of changing of the parameters, noise effect and sampling length show that, both the noise effect and spectrum interference are considered, proving the reliability and high accuracy parameter estimation in a number of engineering applications. Otherwise, the characteristics of efficient computational and low memory demands are advantageously adopted for the poor computing resources situations.