Multivariable Systems

In the last two decades many papers and books on linear systems with several inputs and several outputs, i.e. multivariable systems, have been published. More and more abstract notations and definitions have been introduced in both frequency domain and state space descriptions and other newly developed formalisms. It is not the aim of this last chapter to review this vast amount of literature. The main motivation for this chapter is the observation that some practically important concepts can be made clear and applicable in a simple language if we restrict ourselves to the discrete-time case. This applies in particular to the theory of finite effect sequences (FES) which is developed and applied in this chapter. Therefore this topic seems to be an appropriate conclusion for a book on sampled-data systems.