A Short Note on Output Controllability

Abstract

In this paper we consider output controllability for linear time-invariant systems. In a recent paper by Danhane, Loh{\'e}ac and Jungers it has been pointed out that although output controllability is a classical notion in control theory, only a Kalman-type characterization was available in the literature. In their work that authors consider time-varying linear systems. In this short note we provide a Hautus-type characterization of output controllability for time-invariant linear systems which is more comprehensive and reduces to state controllability in case the output matrix is the identity matrix.