An observer-based chaotic synchronization scheme for time-delay secure communication systems

In this paper, an observer-based chaotic synchronization is studied for a class of time-delay secure communication systems which are subject to delayed state and nonlinear disturbances. The time-delay is allowed to be time-varying, and the non-linearities are assumed to satisfy global Lipschitz conditions. The problem addressed is to design a synchronization scheme which ensures global synchronization of the response system and the driving system for the admissible time-delay as well as nonlinear disturbances. Specifically, some conditions for the existence of the desired observers are derived, and an explicit expression of desired observers is given in terms of some free parameters. A numerical example is presented to show the applicability of the proposed approach.