OICC Press Signal Processing and Renewable Energy (SPRE) 2588-7335 5 3 2021 09 01 Coexisting Behaviors Analysis and Chaos-Based Secure Communication Scheme by a Novel High-Order Nonlinear Autonomous System 1 22 EN Javad Mostafaee Department of Electrical Engineering, Saveh Branch, Islamic Azad University, Saveh, Iran. Saleh Mobayen Department of Electrical Engineering, University of Zanjan, Zanjan, Iran. Behrouz Vaseghi Department of Electrical Engineering, Abhar Branch, Islamic Azad University, Abhar, Iran Mohammad Vahedi Department of Electrical Engineering, Saveh Branch, Islamic Azad University, Saveh, Iran. Journal Article 2021 09 01 This paper constructs a new 6–D hyper–chaotic system with complex dynamic behaviors for se-cure communication scheme. We analyze the chaotic attractor, bifurcation diagram, equilibrium points, Poincare map, Lyapunov exponent behaviors, and Control parameter. The more nonlinear the autonomous system is and the higher the parametric sensitivity it is, the more performative it will be and the more difficult it will be to decode. We will show that the designed system will have attractive and different behaviors due to very small changes in control parameters, which is a sign of the high sensitivity of the system. Then, with the construction of master-slave systems and the design of a new terminal sliding mode controller, the application of the hyper-chaotic system in synchronization and transmission of secure communications is shown. Finally, using the MATLAB simulation, the results are confirmed for the new hyper–chaotic system