On the interpretation of the time-varying eigenvalues

In order to analyse the behaviour in small-signal regime of certain classes of dynamic nonlinear circuits, dynamic linear time-varying (LTV) models must be considered. In an attempt to simplify the analysis of these models, time-varying eigenvalues may be used. In this article, a simple interpretation of those quantities will be given. Time-varying eigenvalues give information on the growth rate of each of the normal solutions of a LTV system in such a way that their dynamics are effectively decoupled from each other. Some arguments are given to support this idea.