Full order observer design for linear systems with unknown inputs

This paper deals with the design of full order observers for linear systems with unknown inputs. Two different approaches are developed using straightforward matrix operations and providing practical design. Specially, it will be noted that when no mention is made on the existence conditions by the first approach [71, the existence conditions are well formulated by the second one [8]. Furthermore, the developments are simple and direct compared to other approaches given in the literature. Design, advantages and drawbacks of the two approaches are illustrated by the same numerical example.