A new observer-based synchronization scheme for private communication

Applying the sliding mode observer strategy, this paper proposes a new observer-based synchronization scheme in the drive-response framework. If a chaotic system (the driving system) satisfies strictly positive real condition, a sliding mode observer (the response system) can be constructed to synchronize the driving system globally. Further, the hidden message can be approximately recovered by the equivalent control signal in the sense of least mean square. Theoretical analysis and numerical simulation show the effectiveness of the proposed scheme.