A NEW APPROACH TO OPERATIONAL MODAL ANALYSIS BASED ON MULTIVARIABLE TRANSMISSIBILITY FUNCTIONS: REVISITED

The concept of using Scalar Transmissibility functions in Operational Modal Analysis was first introduced several years ago. It was immediately clear that using the input-spectrum independent scalar transmissibility functions for modal analysis could yield multiple significant advantages (such as the absence of any white noise assumption typical for OMA). However the use of these functions was limited in situations where multiple uncorrelated forces excite the structure.
To resolve this one can use the multivariable transmissibility functions that again become input-spectrum independent even when multiple uncorrelated forces excite an operational structure. However it was not immediately clear how one could obtain the modal parameters from these multivariable transmissibility functions.
Our research group recently introduced a technique for obtaining modal parameters from these multivariable transmissibility functions.
In this paper we'll discuss and highlight the most recent advances since the introduction of the aforementioned technique and discuss the current state of the art in the use of transmissibility functions for Operational modal analysis.