Robust reduced-order state estimation for the complex network with multiple time-varying delays

This paper is concerned with the problem of state estimation for a class of discrete-time networks with multiple time-varying delays and disturbances, and we aim to design a robust reduced-order state estimator to estimate the states of the network. Different from the construction method of full-order state estimator used widely in the complex network, we only need to estimate the unmeasured part of states in the case of the rest are measurable in the real network. By employing the Lyapunov-Krasovskii functional and H_∞ control approach, delay-dependent criteria are established that ensure the existence of the desired estimator gains, and the explicit expression of such estimator gains is presented in terms of linear matrix inequalities(LMIs). A numerical example is provided to illustrate the effectiveness of the proposed estimator design scheme.