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In this article, the design problem of ℓ2–ℓ∞ proportional–integral observer (PIO) is investigated for a class of discrete‐time systems with mixed time‐delays. The mixed time‐delays comprise both the discrete time‐varying delays and infinitely distributed delays. The round–robin protocol (RRP) is employed to schedule the data transmissions from the sensors to the observer so as to mitigate the communication burden and prevent the data collisions. A novel PIO is developed whose observer gain is dependent on the data transmission order as a reflection of the effects induced by the RRP scheduling. By resorting to the token‐dependent Lyapunov functional and the matrix inequality technique, the desired PIO is designed with exponentially stable error dynamics of the state estimation and guaranteed ℓ2–ℓ∞ disturbance attenuation/resistance capacity. Finally, a simulation example is exploited to verify the validity of the proposed observer design method. [ABSTRACT FROM AUTHOR]

Summary: An event‐triggered nonfragile distributed H∞ control problem is considered in this article for a class of uncertain nonlinear networked control systems over sensor networks with random communication packet dropouts and redundant channels. Redundant channel transmission is utilized to model the communication measurement and to improve the reliability and quality of the communication data transmission services. In addition, measurement size reduction technique is applied to reduce the energy consumption. An event based transmission scheme is employed to reduce the network burden and energy consumption during the data communication from the sensor to the estimator. With known conditional probability distribution, the random packet losses are modeled as a Bernoulli distributed white sequences. A new set of sufficient conditions is established by using average dwell time approach to obtain the desired observer‐based distributed nonfragile controller with the H∞ performance requirements. Specifically, the explicit form of an observer‐based feedback parameters can be obtained by solving a set of linear matrix inequalities. Finally, to demonstrate the effectiveness of the proposed observer‐based feedback approach, a numerical example is exploited. [ABSTRACT FROM AUTHOR]

Summary: In this article, the nonfragile H∞ filtering problem is investigated for a class of discrete multirate time‐delayed systems over sensor networks. The probabilistic packet dropout occurs during the information transmissions among the sensor nodes in the sensor network characterized by the Gilbert‐Elliott model. In order to take the multirate sampling into account, the state updating period of the system and the sampling period of the sensors are allowed to be different. The variation of the filter gain is considered to reflect the physical errors with the filter implementation. The aim of this article is to design a set of nonfragile filters such that, in the presence of multirate sampling, time‐delays, and packet dropouts, the filtering error dynamics is exponentially mean‐square stable and also satisfies the H∞ performance requirement. By using the Lyapunov‐Krasovskii functional approach, a sufficient condition is derived, which ensures the exponential mean‐square stability and the H∞ performance requirement of the filtering error dynamics. Then, the filter gains are characterized in terms of the solution to a set of matrix inequalities. Finally, a simulation example is provided to demonstrate the effectiveness of the proposed filtering scheme. [ABSTRACT FROM AUTHOR]

Summary: This work studies the issue of synchronization control for a type of fractional‐order complex networks, in which the adaptive coupling matrix is considered under the directed topology structure. A pinning control strategy, with the free selection of pinning nodes, is adopted for the synchronization goal. Then, by absorbing the information of eigenvectors and adaptive laws for the coupling matrix, a new Lyapunov function is constructed, by which, and with the assistance of Gronwall inequality and network features, the sufficient condition for Mittag‐Leffler synchronization of the fractional‐order network is established. Accordingly, an easy verifiable algebraic criterion is further derived by means of some matrix inequalities. Besides, we also discuss the effect of outer coupling strength on the achievement of network synchronization. Finally, a numerical experiment is performed to show the evidence of the correctness and effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]