Robuste quadratische Ljapunov-Funktionen

A method is introduced for the determination of quadratic Ljapunov functions with optimized robustness properties for parameter-dependent, continuous or discrete, time-varying or time-invariant linear systems. As a measure of robustness the maximum size of a parameter area of given shape is defined, for which the quadratic form possesses Ljapunov properties. For the determination of this measure theorems on positive definiteness for parameter-dependent Hermitean matrices are given