Estimator-based Control of Networked Systems with Packet-dropouts

This paper is concerned with the stabilization problem for networked control systems (NCSs) with packet-dropouts and delays. A state estimator is incorporated into the controller node, and the controller uses the estimated states when packet-dropouts occur. By using such a estimator-based controller, the closed-loop NCS is modelled as a discrete-time switched systems with both stable and unstable subsystems. Then, a sufficient condition for the exponential stability of the closed-loop NCS is derived by using the average dwell-time method. The obtained stability condition establishes the quantitative relation between the packet-dropout rate and the stability of the closed-loop NCS. Furthermore, design procedures are also presented for the packet-dropout-dependent stabilizing controllers and estimators. Finally, an illustrative example is given to demonstrate the effectiveness of the proposed results.