States observer design and stability analysis for networked control systems

This paper considers the networked control systems whose network-induced delay is likely longer than a sampling period. The continuous time system model with control time-delay is transformed into the discrete time system model with multiple time-delays. Based on the model, a new type full-dimension states observer is designed. A discrete Lyapunov functional method is proposed for the augmented system consisted of the state vector and the error vector to stability analysis. By the method, the asymptotic stability necessary conditions of the augmented system are given. The simulation results show that the method is effective.