Observer-Based Robust Controller Design for a Linear System with Time-Varying Perturbations

In this paper, an observer-based robust controller design problem for the linear uncertain system is considered, where the uncertain system is subject to the norm-bounded and the structured time-varying uncertainties. Using the Riccati approach, full-order and reduced-order observers are obtained to reconstruct the unmeasurable states so that the robust stability of the uncertain system can be guaranteed with the state feedback control law.