Output regulation of general discrete-time linear systems with saturation nonlinearities

This paper studies the classical problem of output regulation for linear discrete-time systems subject to actuator saturation and extends the recent results on continuous-time systems to discrete-time systems. The asymptotically regulatable region, the set of all initial conditions of the plant and the exosystem for which the asymptotic output regulation is possible, is characterized in terms of the null controllable region of the anti-stable subsystem of the plant. Feedback laws are constructed that achieve regulation on the asymptotically regulatable region. Copyright # 2002 John Wiley & Sons, Ltd.