基于辅助驱动信号的一类不确定混沌系统的同步及其在保密通讯中的应用

The Synchronization for a Class of Uncertain Chaotic Systems Based on Auxiliary Drive Signals and Its Application to Secure Communication

针对一类不确定混沌系统,在观测器匹配条件不满足的前提下,讨论了基于观测器设计的混沌同步及其基于混沌同步的保密通讯问题.首先基于相对阶的概念,构造了辅助驱动信号,使混沌系统针对该辅助驱动信号满足观测器匹配条件.接着设计能直接消去非线性项和未知干扰影响的降维观测器作为响应系统来达到混沌同步.然后设计高阶高增益滑模观测器估计辅助驱动信号及微分项.将上述方法应用于保密通讯,提出一种信息还原的方法.最后,针对Ro¨ssler混沌系统进行仿真,结果表明了该方法的有效性.

The problems of observer-based chaos synchronization and chaos synchronization based secure communication are considered when the observer matching condition is not satisfied for a class of uncertain chaotic systems. Firstly, an auxiliary drive signal is constructed based on the concept of relative degree, so that the observer matching condition is satisfied with respect to it. Secondly, for chaos synchronization, a kind of reduced-order observer is developed as the response system which can directly eliminate the influence of the non-linear part and the unknown disturbances of the system. Then, a high-order high-gain sliding mode observer is considered to get the estimation of the auxiliary drive signals as well as their derivatives. The proposed method is applied to the secure communication issues and a kind of message information recovery method is developed. Finally, Rtssler chaotic system is used as a simulation example to verify the effectiveness of the proposed method.