Quantifying Maximum Achievable Accuracy of Identified Modal Parameters from Noise Contaminated Free Vibration Data

This paper derives exact results for the maximum achievable accuracy when estimating modal parameters from free vibration signals contaminated by Gaussian white noise. These limits are found through the Cramer-Rao lower bound. The paper compares the exact findings with previous approximate results found in the literature. Comparisons are drawn with results from stochastic simulations of a Fourier domain approach for estimation of natural frequency and damping in single degree of freedom system.