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对改进恒Lyapunov指数谱混沌系统的广义投影同步进行了研究.用主动控制同步法设计合适的非线性反馈控制器,通过单向耦合,实现恒指数谱混沌系统的同结构广义投影同步与异结构广义投影同步.在指出广义投影同步体系中比例因子调节作用的同时,也分析了改进恒指数谱混沌系统的全局线性调幅参数对同步体系中两个系统的作用.基于模块与复用的设计思想,详细分析并构建了广义投影同步体系中的驱动系统、控制系统与响应系统.数值仿真与电路实验仿真一致显示:调节比例因子能够获得任意比例于原驱动混沌系统输出的混沌信号;调节全局线性调幅参数,能够同时线性调整同步体系中两个系统输出的状态变量的幅值,而不影响两个系统之间的广义投影同步.
关键词:
改进恒Lyapunov指数谱混沌系统
广义投影同步
比例因子
全局线性调幅参数 相似文献
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In an experimental investigation of the response of a chaotic system to a chaotic driving force, we have observed synchronization of chaos of the response system in the forms of generalized synchronization, phase synchronization, and lag synchronization to the driving signal. In this paper we compare the features of these forms of synchronized chaos and study their relations and physical origins. We found that different forms of chaotic synchronization could be interpreted as different stages of nonlinear interaction between the coupled chaotic systems. (c) 1998 American Institute of Physics. 相似文献
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Stefański A 《Chaos (Woodbury, N.Y.)》2008,18(1):013106
This paper is focused on the problem of complete synchronization in arrays of externally driven identical or slightly different oscillators. These oscillators are coupled by common driving which makes an occurrence of generalized synchronization between a driving signal and response oscillators possible. Therefore, the phenomenon of generalized synchronization is also analyzed here. The research is concentrated on the cases of an irregular (chaotic or stochastic) driving signal acting on continuous-time (Duffing systems) and discrete-time (Henon maps) response oscillators. As a tool for quantifying the robustness of the synchronized state, response (conditional) Lyapunov exponents are applied. The most significant result presented in this paper is a novel method of estimation of the largest response Lyapunov exponent. This approach is based on the complete synchronization of two twin response subsystems via additional master-slave coupling between them. Examples of the method application and its comparison with the classical algorithm for calculation of Lyapunov exponents are widely demonstrated. Finally, the idea of effective response Lyapunov exponents, which allows us to quantify the synchronizability in case of slightly different response oscillators, is introduced. 相似文献
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提出了一种基于广义混沌映射切换的混沌同步保密通信方式.这种通信方式首先构建产生多种混沌序列的广义混沌映射模型,然后在不同时段根据切换策略产生不同混沌序列,在发送端,将信号与混沌载波之和取模运算后再嵌入混沌映射的输入端进行迭代运算以实现调制;在接收端,根据切换协议,用同一个相应的广义混沌映射模型从接收信号中提取混沌载波并进而恢复信息信号.研究结果表明:这种基于广义混沌映射切换的混沌同步通信方式比基于单一混沌系统的保密通信方式具有更强的抗干扰能力,保密性能更好,且实现简单.
关键词:
混沌
混沌映射切换
同步
保密通信 相似文献
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J.M.V. Grzybowski E.E.N. Macau T. Yoneyama 《The European physical journal. Special topics》2014,223(8):1447-1463
Pairs of delay-coupled chaotic systems were shown to be able to achieve isochronal synchronization under bidirectional coupling and self-feedback. Such identical-in-time behavior was demonstrated to be stable under a set of conditions and to support simultaneous bidirectional communication between pairs of chaotic oscillators coupled with time-delay. More recently, it was shown that isochronal synchronization can emerge in networks with several hundreds of oscillators, which allows its exploitation for communication in distributed systems. In this paper, we introduce a conceptual framework for the application of isochronal synchronization to TDMA communication in networks of delay-coupled chaotic oscillators. On the basis of the stable and identical-in-time behavior of delay-coupled chaotic systems, the chaotic dynamics of distributed oscillators is used to support and sustain coordinate communication among nodes over the network. On the basis of the unique features of chaotic systems in isochronal synchronization, the chaotic signals are used to timestamp clock readings at the physical layer such that logical clock synchronization among the nodes (a prerequisite for TDMA) can be exploited using the same basic structure. The result is a standalone network communication scheme that can be advantageously applied in the context of ad-hoc networks or alike, especially short-ranged ones that yield low values of time-delay. As explored to its depths in practical implementations, this conceptual framework is argued to have potential to provide gain in simplicity, security and efficiency in communication schemes for autonomous/standalone network applications. 相似文献
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Heng-Hui Chen 《Physics letters. A》2008,372(11):1841-1850
This Letter introduces linear balanced feedback control scheme to design controller for the synchronization of two identical chaotic systems based on Lyapunov stability theory and constrained extreme approach. The technique is applied to synchronizing two identical four-scroll chaotic systems and guiding balanced feedback gains design. In accordance with the result of the analysis, an adaptive control scheme is proposed for chaos synchronization when the parametric variations of the response system are uncertain. The feasibility and effectiveness of the proposed synchronization scheme are verified via numerical simulations. 相似文献
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In this Letter, based on robust control, we provide a general theoretical result on stochastic linear generalized synchronization (GS) of chaotic systems. Given a driving system with noise perturbations and a linear synchronization function, a response system is developed easily according to the scheme derived here. By introducing the Lyapunov stability theory and linear matrix inequalities (LMIs), the condition for synchronization is proved to be effective. Finally, the Lorenz system is taken for illustration and verification. 相似文献
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The synchronization problem for a general class of uncertain chaotic systems is addressed. The underlying systems may be perturbed by unknown time-varying parameters, unstructured uncertainties, and external disturbances. Meanwhile, the time-varying parameters and disturbances are neither required to be periodic nor to have known bounds. Assuming the disturbances are L(2) signals, an adaptive control incorporated with H(∞) control technique is employed to construct a robust adaptive synchronization algorithm. Then, removing such assumption, a novel adaptive-based method is developed to achieve the goal of synchronization. In order to demonstrate the effectiveness of the proposed algorithms, such methods are applied to solve the synchronization problem of uncertain chaotic Chua's circuits. 相似文献
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提出多量子阱激光器混沌“主-从-响应”式结构同步系统,研究其并联同步在光学逻辑门中的应用. 利用一个注入多量子阱激光器混沌系统注入驱动实现了两个响应多量子阱激光系统的混沌并联同步,同时还获得了“主-从”式结构的混沌同步. 基于响应子系统的混沌并联同步思想,提出了全光逻辑门的基本理论模型并定义了计算原则与方法. 利用光的外部调制方法对两个驱动光进行调制与控制,让两个响应子系统实现同步与非同步,使系统获得了并具有全光逻辑门函数功能与特点,并成功地进行了数字逻辑计算. 具体提出了全光XNOR、NOR、NOT等逻辑门及逻辑计算方法,数值模拟结果证明了系统方案的可行性.
关键词:
混沌
同步
逻辑门
多量子激光器 相似文献
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We examine synchronization of identical chaotic systems coupled in a drive/response manner. A rigorous criterion is presented which, if satisfied, guarantees that synchronization to the driving trajectory is linearly stable to perturbations. An easy to use approximate criterion for estimating linear stability is also presented. One major advantage of these criteria is that, for simple systems, many of the calculations needed to implement them can be performed analytically. Geometrical interpretations of the criterion are discussed, as well as how they may be used to investigate synchronization between mutual coupled systems and the stability of invariant manifolds within a dynamical system. Finally, the relationship between our criterion and results from control theory are discussed. Analytical and numerical results from tests of these criteria on four different dynamical systems are presented. (c) 1997 American Institute of Physics. 相似文献
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改进恒Lyapunov指数谱混沌系统的特殊的分段线性结构及其全局线性调幅参数与倒相参数的存在性,赋予了其同步体系新的可实现性与可调节性.依据广义同步的原理,构造合适的驱动系统与响应系统,可以实现恒Lyapunov指数谱混沌系统的广义同步;改变响应系统的参数,可实现完全同步与广义投影同步;改进恒Lyapunov指数谱混沌系统的全局线性调幅参数能对驱动与响应系统的状态变量幅值实施同步升降控制,倒相参数能对某一特定状态变量实施同步倒相控制.这种同步体系无需专门的控制器,结构简单,易于实现.文章最后设计了同步体系的实现电路,实验仿真结果证明了混沌同步方法的可行性,也验证了恒指数谱混沌系统特殊参数对同步体系状态变量幅值与相位的调控作用. 相似文献
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随机源对于信息理论安全的密钥分发至关重要,本文提出了一种基于单向注入垂直腔面发射激光器系统的密钥分发方案.首先基于单向注入的方式产生无时延特征的激光混沌信号,并通过单向注入驱动两个从激光器产生带宽增强的混沌同步信号.然后经过采样、量化以及异或等后处理,生成密钥流.数值仿真结果表明,在单阈值情况下,合法用户之间的误比特率低至1%左右,合法用户与窃听者之间的误比特率都高于10%;在双阈值情况下,误比特率可以低至10-6.最后,对生成的密钥流进行了NIST随机性测试.该方案有效地增强了密钥分发的安全性. 相似文献
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This paper presents a synchronization method, motivated from the constructive
controllability analysis, for two identical chaotic systems. This technique is
applied to achieve perfect synchronization for Lorenz systems and coupled dynamo
systems. It turns out that states of the drive system and the response system are
synchronized within finite time, and the reaching time is independent of initial
conditions, which can be specified in advance. In addition to the simultaneous
synchronization, the response system is synchronized un-simultaneously to the drive
system with different reaching time for each state. The performance of the resulting
system is analytically quantified in the face of initial condition error, and with
numerical experiments the proposed method is demonstrated to perform well. 相似文献