Abstract:

Due to their intrinsic randomness, sensitivity to initial values and broadband spectrum, chaotic systems have been used to implement secure communication. To improve security and enhance anti-interference ability, a four-dimensional hyperchaotic system with unknown parameter is designed based on the classical Lorenz chaotic system. A single signal control is proposed based on sliding mode adaptive control to synchronize hyperchaotic systems with the same structure. When synchronization is achieved, the hidden signal can be restored effectively at the receiving end. Numeric simulation shows effectiveness of the proposed technique.

Key words: secure communication, hyperchaotic system, Lorenz system, sliding mode control, adaptive synchronization