Linear functional observers for systems with delays in state variables

Abstract

This paper is concerned with the design of linear functional state observers for systems with delays in state variables. In particular, the necessary and sufficient conditions for the existence of the rth-order observers are given. Sufficient conditions for the stability dependent of delays and stability independent of delays are derived using linear matrix-in-equality formulation. A systematic design method of these observers is presented. Numerical examples are given to illustrate this method.