Some properties of the frequency domain description of boundary control systems

Abstract

In this paper we make use of the semigroup approach to study a boundary control system with possibly unbounded output operator. Input and output functions take values in finite dimensional spaces. We define the class of “modally canonical systems” and we show that a system of this class, which satisfies suitable conditions, can equivalently be described by the “system operator matrix” as well as by the transfer function. The implications of the canonicity assumption on the structure of the system are examined.