Disturbance decoupled observer design for linear time-invariant systems: Amatrix pencil approach

In this paper we give a new analysis of the observer design problem for lin ear time-invariant systems with partly unknown inputs. We use a matrix penc il approach that is based on a condensed form under orthogonal transformati ons. The solvability conditions that we obtain can be verified and the desi red observer can be constructed by a numerically stable method.