Résumé:
Since the main characteristics of chaos, such as sensitivity to initial conditions, randomness, unpredictability and complexity can be attached with the well-known confusion and diffusion properties of cryptography, there has been tremendous interest world-wide in the possibility of using chaos in communication systems. Therefore, it is of significant interest to design suitable chaotic systems for secure, cost-effective and robust communications.
The first contribution of this thesis is to design a new chaotic system with high complexity and large bandwidth compared with the existing chaotic systems. The second contribution is to develop a new n-dimensional multistable hyperchaotic system with (n>7) and multiple coexisting attractors. The third contribution is to construct new n-dimensional hyperchaotic systems with (n>7) and (n-2) positive Lyapunov exponents. The last contribution is to construct a new delayed discrete-time hyperchaotic system and propose a new approach for delay estimation and information recovery for delayed discrete-time chaos-based secure communication.
