An adaptive observer synchronization using chaotic time-delay system for secure communication

Recently, the time delay has considerable attention in the existence of chaos in the nonlinear dynamical systems. In this paper, we therefore develop a new cascade-coupled chaotic synchronization model based on the first-order nonlinear time-delayed chaotic system using the simple Lur'e system to provide more robust secure system. Adaptive observer-based master systems are designed to synchronize with the given chaotic slave systems at the receiver where the dynamical model is subjected to certain time delay values at the slave systems. Two cases of being system parameters match and mismatch are considered. The adaptive observer laws are carefully designed to confirm the convergence of error dynamics. Numerical simulations reveal the effectiveness of the time delay on the recovered message security using the chaotic masking technique. As a result, the information message is able to be recovered correctly with sufficient precision over the noiseless and noisy channels and under predefined time-delay values compared to the existing systems.