Non-stationary frequency domain system identification using time–frequency representations

Non-linear System Identification Using Frequency Domain Measurement Data

In this paper, an efficient method for identifying non-linear element positions and their physical parameters within a multiple degree of system or structure is presented. The local non-linear stiffness and damping restoring forces are first modeled with polynomial series functions of the relative displacements and velocities, respectively. Second, an iterative equation between excitation and r...

Frequency Domain System Identification

Time-Frequency Domain Characterization of Stationary and Non stationary Signals

Abstract-This paper presents the various methods for the spectral analysis of signals for the stationary as well as non-stationary signals. Due to non-stationary characteristics of the signals, it has been always a challenge to achieve time frequency distribution of such signals. Between the various techniques of signal analysis, this paper uses Fourier transform, Short time Fourier transform, ...

Comparison of Non-Stationary Time Series in the Frequency Domain

In this paper we compare two non-stationary time series using non-parametric procedures. Evolutionary spectra are estimated for the two series. Randomization tests are performed on groups of spectral estimates for both related and independent time series. Simulation studies show that in certain cases the tests perform reasonably well. The tests are applied to observed geological and financial t...

A new frequency domain system identification method

A new frequency domain system identification method based on a multi-frequency input signal is proposed. Frequency contents of the oscillating signal are estimated using a modified Kaczmarz algorithm proposed in this paper. Lyapunov stability analysis is performed for this new Kaczmarz algorithm and transient bounds for estimation error are established. Moreover, a new method for estimation of ...