Minimal partial realization by descriptor systems Original Research Article

In this paper a generalization of Kalmanʹs partial realization theory is developed using partial realizations defined by descriptor systems. The use of singular system realizations in contrast to regular linear systems enables us to circumvent certain technical difficulties inherent in the standard approach to partial realizations. An existence and uniqueness result for minimal partial descriptor realizations is proven and a simple rank formula for the McMillan degree is derived.