Özet:

Time delays are often instability sources and give rise to undesired oscillation and performance degradation, so it is necessary to consider delay in general congestion control schemes. In this paper, a new system model for wireless sensor networks (WSNs) is established in discrete time, subsystems including delay are presented, and the overall model is achieved by blending these subsystems. For controller synthesis, common quadratic Lyapunov functions and a new approach based on nonquadratic Lyapunov functions are utilized, and a controller is designed to stabilize each subsystem. The controller synthesis results are expressed in terms of linear matrix inequalities. Moreover, the performance of our proposed scheme is considered and the decay rate is guaranteed. Finally, a set of novel congestion control schemes is derived for WSNs, and the resulting closed-loop systems are globally asymptotically stable in case of queue length changes and the consequent delay changes. The simulation results are also presented to illustrate the effectiveness of our proposed method.

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