Estimation of modal parameters using bilinear joint time–frequency distributions

In this paper, a new method is proposed for modal parameter estimation using time–frequency representations. Smoothed Pseudo Wigner–Ville distribution which is a member of the Cohen's class distributions is used to decouple vibration modes completely in order to study each mode separately. This distribution reduces cross-terms which are troublesome in Wigner–Ville distribution and retains the resolution as well. The method was applied to highly damped systems, and results were superior to those obtained via other conventional methods.