An observer theory for time delay systems

A theory of Luenberger type of observers for time-delay systems based on spectral decomposition techniques is developed. The stability, of the observer is rigorously established and the observer equations are reduced to an integro-differential form. The computational aspects are discussed and the difficulty is traced to that of computing eigenvalues of delay differential equations. Formal structural similarities of Kalman filters for delay systems and the observer developed here are indicated.