Reduced order linear functional observers for large scale linear discrete-time control systems

For the last five decades, there has been great interest in the control literature in deriving reduced order models for large-scale linear control systems. Such reduced order models have great applications in science, engineering and industry. In this paper, we have studied the problem of designing linear functional observers for large-scale linear discrete-time control systems and derived some new results, viz. necessary and sufficient conditions for the reduced order linear functional observer for discrete-time linear control systems. We have also established a separation principle for implementation of an observer-based feedback stabilization scheme. A simple algorithm has been provided for the ready implementation of the proposed linear functional observer. A numerical example using MATLAB has been provided to illustrate the new design procedure.