Transfer function phase and truncated impulse response

Abstract

Transfer function (TF) phase can be analyzed from the impulse response in a vibrating system. This letter analyzes the truncated impulse response of such a system and its phase characteristic by using a simple two-pole model. The estimated phase turns out to be highly sensitive to the window length of the truncated impulse response used for phase analysis. The minimum-phase behavior of a TF for example, is changed into a nonminimum-phase characteristic due to the truncation. An exponential window is recommended for the data analysis of vibrating systems in order to reduce the effect of truncation on the phase.