参数扰动下的混沌同步控制及其保密通信方案

研究了变参数混沌系统的同步控制问题及其保密通信方案设计.主要创新点可归结如下:第一,提出了利用混沌系统状态变量来构造变参数系统参数扰动项的思想,研究了混沌系统参数在另一组混沌序列持续扰动下的同步控制问题.混沌系统对参数具有敏感依赖性,当混沌系统的参数被另一组混沌序列持续扰动时,系统将产生更加难以预测的混沌行为.第二,对加密后的信息信号再进行一次非线性叠来生成加密端与解密端之间的通信信号,而不是直接以加密信号作为通信信号,使得实际传输的通信信号具有更复杂的形式从而难以被破译.此外,该方案只需向接收系统发送一路信号,且同步控制器简单,实用性较强.数值模拟和理论分析表明该方案具有良好的通信、保密特性和较广的适用范围.

Chaotic synchronization with parameter perturbation and its secure communication scheme

The synchronization of chaotic system with variable parameters is investigated; the corresponding secure communication scheme is also proposed. The main innovations can be listed as follows. First, the parameter perturbation items adopted in this paper are not periodical signals but chaotic signals. This process can make a chaotic system present more complicated dynamical behavior. Secondly, a unidirectional couple controller is designed to realize the present synchronization. On the other aspect, a nonlinear superposition procedure is introduced to generate the transmitted signal. In many existing chaos-based secure communication schemes, the encrypted signal plays the role of the transmitted signal directly. However, in this paper, the transmitted signal is obtained by adding the encrypted signal with several chaotic signals. This procedure enhances the security of the algorithm. Besides, only one signal is needed to be transmitted in this algorithm and the controller is also simple; this means that the proposed algorithm is feasible and practical. Numerical simulations and theoretical analysis show that this algorithm is secure, efficient and generally applicable.