Contribution to the conception of chaotic systems for secure data transmission

Abstract

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.