High gain observer synchronization for a class of time-delay chaotic systems. Application to secure communications.

This work investigates high gain observer design to synchronize a time-delay chaotic system. It is shown that the underlying class of nonlinear systems can be put into the canonical observable form, and thus high gain observer design framework can be extended to chaotic synchronization problem. Our approach is motivated by its simplicity of implementation: the observer gain synthesis relies on the explicit resolution of a time-invariant algebraic Lyapunov equation, which leads to a single parameter design. The proposed synchronization scheme is validated in a real-time experimental setup, based on Analog/Digital dSpace electronic device. At the end of the paper an information transmission process is provided, based on the previous synchronization scheme.