Determination of structural modes via the Prony model: System order and noise induced poles

Abstract

The parameters of multiple degree of freedom structural systems can be identified from their impulse response via the Prony method. Overdetermining the system’s order is shown to improve the identification accuracy in noisy situations, but introduces additional mathematical poles. Described are methods to determine the necessary overdetermination and the true system poles. A novel, efficient perturbation method, based on the singular value decomposition, is shown to be effective under noisy situations.