Complex Analysis and Operator Theory

, Volume 4, Issue 2, pp 319–390 | Cite as

Well-Posed State/Signal Systems in Continuous Time

  • Mikael KurulaEmail author
  • Olof J. Staffans


We introduce a new class of linear systems, the L p -well-posed state/signal systems in continuous time, we establish the foundations of their theory and we develop some tools for their study. The principal feature of a state/signal system is that the external signals of the system are not a priori divided into inputs and outputs. We relate state/signal systems to the better-known class of well-posed input/state/output systems, showing that state/signal systems are more flexible than input/state/output systems but still have enough structure to provide a meaningful theory. We also give some examples which point to possibilities for further study.


Systems theory State/signal systems Infinite-dimensional systems Well-posed systems System nodes Input/state/output systems 

Mathematics Subject Classification (2000)

Primary 93A05 47A48 Secondary 93B28 94C05 


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Copyright information

© Birkhäuser Verlag Basel/Switzerland 2009

Authors and Affiliations

  1. 1.Department of MathematicsÅbo Akademi UniversityÅboFinland

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