H∞ control of networked control systems with packet disordering

This study is concerned with H _infin control of networked control systems with long delay and packet disordering. A new mathematical model of networked control systems, fully describing the phenomenon of packet disordering and effectively eliminating the impact of packet disordering on the performance of the systems, is proposed. Different from the existing methods, this model is converted into a parameter-uncertain discrete-time system with multi-step delay based on matrix theory. Furthermore, an improved Lyapunov-Krasovskii functional is proposed to derive less conservative H _infin stabilisation criteria. By solving a minimisation problem based on linear matrix inequalities, an H _infin controller is obtained. Finally, numerical examples are given to illustrate the effectiveness of the proposed method.