A Novel Switched Chaotic Model

The fact that chaotic systems are implemented with finite precisions in digital computers leads to dynamical degradation of the original systems. The most well known problem of the degradation is the existence of short cycle length, which can reduce the security of the designed chaotic ciphers. To solve the dynamical degradation problem, this paper introduces a novel switched chaotic system. The system consists of two different subsystems and can change its structure timely and randomly from one to another, using a switching function. This is equivalent to random perturbations for system variables and parameters, and the random perturbations operate automatically under the control of its own state variables, no needing extra random-like controlling signals. The proposed chaotic system should be very useful for the consideration of reducing negative influence of dynamical degradation in practical design of various digital PR sequences.