Smooth Adaptive Sliding Mode Observers in Uncertain Chaotic Communication

We study the performance of adaptive sliding mode observers (ASMO) in chaotic synchronization and communication in the presence of uncertainties. The proposed robust adaptive observer-based synchronization is used for cryptography based on non-linear chaotic masking modulation (NCM). Uncertainties are intentionally injected into the chaotic dynamical system to achieve higher security and we use robust sliding mode observer design methods for the uncertain non-linear dynamics. In addition, a relaxed matching condition and a boundary layer smooth gain are introduced to realize the robust observer design more feasibly. A brief study in introducing an alternative augmented ASMO-based chaotic communication configuration will be discussed. Finally, a Lorenz system is employed as an illustrative example to demonstrate the effectiveness and feasibility of the proposed cryptosystem.