【作者】 兀旦晖；

【导师】 柯熙政； 刘小河；

【作者基本信息】 西安理工大学 ， 电路与系统， 2004， 硕士

【摘要】 本文主要研究了混沌系统和混沌系统同步保密通信中的若干问题。 混沌是非线性确定系统中由于内禀随机性而产生的外在复杂表现，是一种貌似随机的非随机运动。它的基本特征之一是系统对初始条件的极端敏感性，即初始条件的微小差异会随时间的演化呈指数增长，最终不可接受。其长期行为表现出明显的随机，如不加以控制，根本无法应用。 混沌控制和混沌系统应用于保密通信的研究已成为信息科学界关注和研究的热点问题，虽然已取得了许多成果，但远未达到实际应用的阶段。本文在分析了已有研究成果的基础上，进行了以下方面的研究： 1)针对Lorenz混沌电路，给出电路方程参数与元件值之间的关系，可以从元件数值判断电路是否产生混沌现象；针对目前研究最广泛的Chua电路，利用模拟电感改进了Chua电路，便于电路的工程实现。 2)混沌保密通信中，混沌同步是一项关键技术。本文针对驱动—响应式Chua电路混沌同步系统，提出混沌同步系统的自保持特性，解决了目前在混沌保密通信中，如何在同一信道中同时传输明文信息和混沌同步控制信号，为混沌同步在工程、通信领域的实际应用奠定了基础。 3)对蔡氏电路单向耦合混沌同步系统的失真—频率特性进行了理论分析，并对蔡氏电路的设计原则以及混沌信号的带宽估计进行了讨论。在此基础上提出了两西安理工大学硕士学位论文级调制的混沌掩盖通信方式，用以改善解调信号的保真度。 4)设计了一个用户界面，可对Chua混沌电路的参数、初始条件、特征值、矢量场、运动轨迹等各个环节进行全面、直观的反映，解决了目前研究Chua混沌电路各环一竹的不直观性和计算电路参数的复杂性，可使研究者更进一步方便的研究电路。此软件具有应用与推，’‘价值。更多还原

【Abstract】 This thesis is concerned with some problems of chaotic system and chaotic sychronization secure communication.Chaos is a outer complex behave of nonlinear definite system, produced by the system’s internal random property, a non-random movement while it looks like random. The one of its basic characteristics is that the system is highly sensitive to original condition, that is to say, the system’s output, with the time went by, assumes index increase because of the system’s little difference of original condition, can’t be accepted, it could not be used without being controlled.The study of chaotic control and chaotic secure communication has become a hotspot problem of info-sci field, many achievements have acquired, but it doesn’t much too reach practical application phase. On the base of achieved research production, the following study aspects are carried through in this thesis:1) In allusion to Lorenz chaos circuit, the relation of circuit equation’s parameters to elements’ values is put forward, as a result, that whether the circuit engenders chaotic phenomenon can be easily estimated. With respect to the Chua’s circuit, a simulated inductor is designed, Chua’s circuit is also improved by means of simulated inductor, and then, it becomes very easy to make Chua circuit apply to practical engineering.2) In the field of chaos secure communication, chaos synchronization is a key technology. In view of drive-response Chua’s circuit chaotic synchronization system, chaos synchronization self-maintenance is put forward in this thesis, it solves the present problem of how to stimulatingly transmit useful signal and chaos synchronization control signal in the same one channel, as a result, it establishes the groundwork of putting chaos into practical application of engineering and communication field.3) To theoretically analyze the distortion-frequency characteristic of Chua’s circuit and discuss the chua circuit’s design principle and chua signal’s bandwidth estimation. Depend on its above, a tow-grade modulation chaos masking communication is put forward in order to improve demodulation signal’s fidelity.4) A user’s interface is designed in this paper. Utilizing the interface, all most aspects of chua’s circuit, including circuit’s parameters, initial conditions, eigenvalues, vector field, movement track, and so on, may be fully and directly reflected. On the one hand, it solves existing situation of no-directly perceived nature and complexity in researching all aspects of Chua’s circuit; on the other hand, investigators can still more conveniently study the circuit. As a whole, the software endows with application and extension value.更多还原