Interconnections of Input/Output Behaviors

Complex systems are often obtained by interconnecting more elementary input/output behaviors. For example, every state-space system with proper transfer matrix can be constructed by interconnecting elementary building blocks, namely, adders, multipliers, and integrators (continuous time) or delay elements (discrete time). Basic types of interconnections are the series or cascade connection, the parallel connection, and the feedback interconnection. The latter is fundamental for the construction of stabilizing compensators and for controller design in Chap. 10.