System identification using wavelet analysis

System identification (SID) plays a central role in any activity associated with process operations. With control being done on different levels, different models are required for the same plant each for a different range of dynamics. Besides that most identification methods apply to the linear models, they also do not allow for selecting a frequency range. Wavelet methods have the ability to select the time and frequency windows and are also applicable to the nonlinear processes. The paper presents an approach, in which wavelet transform is used for SID enabling selection of the particular frequency range. Even though, the wavelet transform as a tool is known for a long time and has a number of desirable properties, it is not frequently used in the applications.