The paper concerns techniques of modal model quality improvement at the stage of data pre-processing for the purposes of identification process. Basic concepts of problem formulation (matrix conditioning) improvement by the use of the Tikhonov regularization method are presented as well as examples of method application to solution estimation of the Fredholm integral equation of the first kind and to transfer function matrix noise reduction. In the second part of the paper the authors proposed the method for transfer function estimation on the basis of data measured by the use of impulse test on big industrial systems for which classical methods fail for the reason of low coherence between exciting force and system response. Two examples of method application are presented.
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