H∞ filtering for a class of nonlinear systems with interval time-varying delay

In this paper, a delay-dependent H∞ filtering problem is investigated for discrete-time delayed nonlinear systems which include a more general sector nonlinear function instead of employing the commonly used Lipschitz-type function. By using the Lyapunov-Krasovskii functional approach, a less conservative sufficient condition is established for the existence of the desired filter, and then, the corresponding solvability condition guarantee the stability of the filter with a prescribed performance level. Finally, two simulation examples are given to show the effectiveness of the proposed filtering scheme.