摘要
混沌因其天然具有类随机性、初值敏感性等复杂动力学特性被广泛应用于信息安全及其保密通信领域中。整数阶低维混沌系统存在着安全隐患，而分数阶时滞系统难以被常规攻击手段攻破且拥有更大的密钥空间，在保密通信领域中有着更广阔的应用空间和实用价值，因此构造分数阶时滞混沌系统是提高保密通信系统安全性的有效途径。Hopfield神经网络在一定条件下能够直接生成具有良好扩散效应的混沌矩阵，本文以一类分数阶时滞Hopfield神经网络为模型，研究其复杂的动力学特性包括混沌现象以及同步问题，同时将其应用于保密通信方案中。
首先，提出一类新的分数阶时滞Hopfield神经网络并分析其复杂动力学行为。理论上证明了系统平衡点的唯一性。在无延时下，利用分数阶稳定性定理给出了分数阶阶次与系统稳定性的关系；在延时参数变化时，发现系统通往混沌的道路为阵发性混沌道路，通过相图、分岔图、最大Lyapunov指数、排列熵对其加以验证。
然后，基于状态观测器理论，研究一类分数阶时滞神经网络的广义投影同步问题。基于分数阶稳定性定理和极点配置技术给出了反馈增益矩阵的设计方法，并以分数阶时滞Hopfield神经网络为例进行数值仿真实验，验证了同步方案的可行性和正确性。
最后，基于状态观测器同步方案，给出了一种混沌掩盖保密通信框架。其中信源信号经过预处理之后直接参与到混沌信号的产生中，通过理论分析和数值仿真实验验证了该框架的可行性。仿真分析了反馈增益矩阵参数失配下的同步以及加解密过程。给出了我们的混沌系统与其他一些用于加密的混沌系统的复杂度对比。最后指出了该框架相对于传统混沌掩盖通信方案的优点所在。
关键词：混沌系统混沌保密通信分数阶时滞系统Hopfield神经网络广义投影同步关于除夕的诗句
ABSTRACT
Chaotic quences are widely ud in information curity and cure communication fields due to their inherent complex dynamics such as quasi-randomness and initial value nsitivity. The integer-order low-dimensional chaotic system has curity risks, and the fractional-order time-delay system is difficult to be attacked by conventional attack methods and has a larger key space. It has wider application space and practical value in the field of cure communication, so constructing the chaotic system with order delay is an effective way to improve the curity of cure communication systems. Hopfield neural network can directly generate chaotic matrix with good diffusion effect under certain conditions, this thesis us a class of fractional-order time Hopfield neural network as
a model to study its complex dynamic characteristics including chaotic phenomena and synchronization problems. It is ud in cure communication schemes.
Firstly, a new class of fractional-order Hopfield neural networks is propod and its complex dynamic behavior is analyzed. Theoretically proved the uniqueness of the system equilibrium point. Under the no-delay, the relationship between the fractional order and the stability of the system is given by the fractional stability theorem. When the delay parameters change, the road leading to chaos is found to be a paroxysm chaotic road. , the bifurcation diagram, the largest Lyapunov exponent, and the permutation entropy are ud to verify it.
五行汤做法与功效Then, bad on state obrver theory, the generalized projection synchronization problem for a class of fractional-order delay neural networks is studied. The design method of feedback gain matrix is given bad on fractional stability theorem and pole placement technique. The numerical simulation experiment is carried out by taking Hopfield neural network with fractional delay as an example. The feasibility and correctness of the synchronization scheme are verified.
Finally, bad on the state obrver synchronization scheme, a chaotic masking cret communicati
on framework is prented. The source signal is directly involved in the generation of chaotic signals after preprocessing. The feasibility of the framework is verified by theoretical analysis and numerical simulation experiments. The synchronization and the encryption and decryption process under the feedback gain matrix parameter mismatch are analyzed. The complexity comparison between our chaotic system and other chaotic systems for encryption is given. Finally, the advantages of the framework over the traditional chaotic cover communication scheme are pointed out.
Key words: Chaotic system Chaotic cure communication Fractional delayed system Hopfield neural network Generalized projective synchronization
目录
摘要................................................................................................................. . II 1 绪论. (1)
1.1研究背景及意义 (1)
1.2国内外研究现状 (3)
职业决策选择
1.3本文主要工作内容及结构 (9)
2 基础理论及方法 (11)
2.1引言 (11)
2.2分数阶微积分的定义 (11)
2.3分数阶微分方程数值仿真算法 (12)
北京旅游攻略3日游2.4分数阶微分系统的稳定性定理 (15)
2.5混沌系统的分析与判定方法 (17)
途中寒食
2.6本章小结 (22)
3 一类分数阶时滞HOPFIELD神经网络动力学特性分析 (23)
3.1引言 (23)
3.2系统模型描述 (24)
3.3系统动力学行为分析 (25)
渣男的标准3.4本章小结 (35)
亚洲十页4 一类分数阶时滞神经网络的广义投影同步及其保密通信 (37)
4.1引言 (37)
4.2分数阶时滞神经网络的广义投影同步 (38)
4.3混沌保密通信 (42)
4.4本章小结 (52)
5 总结与展望 (53)
5.1全文总结 (53)
形容年纪大的成语
5.2课题展望 (54)
致谢 (56)
参考文献 (57)
附录1 攻读硕士学位期间发表的论文 (64)
附录2 攻读硕士学位期间参与的课题研究情况 (65)
