一个新的开关超混沌及其DSP实现

为了提高混沌的复杂性,提出了一个开关超混沌系统。该系统包含2个不同的超混沌子系统,其结构和参数在其自身变量的控制下不断地在这两个子系统之间变化,其行为比传统的超混沌更具复杂性。为产生数字超混沌信号,基于DSP芯片研究了该开关超混沌系统的数字化实现问题,在实验中获得了数字化的混沌序列。该系统及其数字化方法可应用于通信、信息加密和计算机等领域之中。     

一个新的超混沌系统及其电路实现

通过对一个光滑三维二次混沌系统上引入一个新的状态反馈控制器,构造出一个新的四维超混沌系统。详细地分析了该系统平衡点的性质、超混沌吸引子相图、Lyapunov指数和分岔图等基本动力学特性。数值模拟结果表明,新的四维系统能随着参数变化呈现出周期态、拟周期态、混沌态和超混沌态等丰富的动力学行为。最后设计了硬件电路实验,也很好的证实了相关结果。     

A switched hyperchaotic system and its FPGA circuitry implementation

This paper introduces a switched hyperchaotic system that changes its behavior randomly from one subsystem to another via two switch functions, and its characteristics of symmetry, dissipation, equilibrium, bifurcation diagram, basic dynamics have been analyzed. The hardware implementation of the system is based on Field Programmable Gate Array (FPGA). It is shown that the experimental results are identical with numerical simulations, and the chaotic trajectories are much more complex.     

Multi-scroll hyperchaotic system based on colpitts model and its circuit implementation

Based on the framework of Colpitts oscillator, a four-dimensional multi-scroll hyperchaotic system is proposed, which generates (2M+1)×(2N+1)-scroll chaotic and hyperchaotic attractors. The key strategy is to increase the number of index-2 equilibrium points by introducing two unit saw-tooth functions to extend and modify the Colpitts oscillator model. By using bifurcation diagram and phase portrait, the dynamical characteristics of the multi-scroll hyperchaotic system are briefly studied. Moreover, micro-controller based circuit realization is introduced and the experimental results demonstrate that 7×5-scroll chaotic and hyperchaotic attractors can be obtained in the digital circuit.     

超混沌复系统的自适应广义组合复同步及参数辨识

该文针对含未知参数的异结构超混沌复系统,基于自适应控制及Lyapunov稳定性理论,提出一种新的自适应广义组合复同步方法 (GCCS)。首先给出广义组合复同步的定义,将驱动-响应系统的同步问题转化为误差系统零解的稳定性问题;然后从理论上设计了非线性反馈同步控制器及参数辨识更新律,并引入误差反馈增益,以控制同步的收敛速度;最后以超混沌复Lorenz系统、超混沌复Chen系统、超混沌复L系统的广义组合复同步与参数估计为例,从数值仿真角度验证了所提方法的正确性和有效性。     

A study on hyperchaotic system implemented by SETMOS

In this paper, we proposed a hardware implementation method for generating a sandwich hyperchaotic attractor. Based on the negative differential conductance (NDR) characteristic of hybrid single-electron transistor and complimentary metal-oxide-semiconductor (SETMOS) architecture, Saito hysteresis chaos generator (SHCG) was constructed using a cellular neural network (CNN). Complex dynamical behaviors of the hyperchaotic system were investigated by means of bifurcation diagram, Lyapunov exponent spectrum, Poincaré mapping and power spectrum. Numerical simulations verify the theoretical analysis and design method and show that the implemented hyperchaotic circuit works very well.     

一个新的超混沌系统设计与实现

在三阶Qi系统的基础上,构造了一个具有两个较大正的Lyapunov指数和较大参数范围新的超混沌系统,分析了该系统的平衡点及稳定性,Lyapunov指数谱和分形维数,超混沌吸引子的相图等特性,并利无量纲状态方程的模块化设计方法实现了该系统,实验结果与仿真结果完全一致。     

超混沌序列对DS-UWB多址性能的改善

利用Roessler超混沌系统构造了一种新的超混沌序列,分析了序列的相关特性,并将其应用于直接序列超宽带（DS—UWB）系统中,以提高它的误码性能。建立了DS-UWB通信系统的模型,以超混沌序列作地址码对高斯白噪声信道中多用户DS—UWB系统误码率进行了分析,并将其与m序列作地址码时的相应性能进行了比较。由分析和仿真可知,构造的新的超混沌序列能较好地改善DS-UWB的多址性能。     

扰动下一类超混沌系统的同步及其在保密通信中的应用

本文基于状态观测器方法,在扰动存在的情况下,对一类超混沌系统的同步及其在保密通信中的应用问题进行了研究。研究表明,本文所给的方法克服了扰动对系统同步所造成的影响,使得系统保持着良好的同步。另外,本文考虑的超混沌系统,对保密通信系统有着较高的保密性,因此本文的方法在实际中更加可行。     

一个超混沌系统及其投影同步

 通过在Lorenz系统中加入两个控制器构造出一个五维超混沌系统,系统的超混沌特性通过Lyapunov指数得到验证,对系统的平衡点和耗散性进行了分析.基于线性系统的稳定性准则,利用线性分离方法实现了该超混沌系统的投影同步.     

超混沌电路的广义同步

该文研究了超混沌电路的广义同步,理论分析表明:只要构造出恰当的矩阵和一个与之相对易的矩阵,就可以实现驱动系统与响应系统的广义超混沌同步。文章并以一个四维超混沌振荡电路为例,给出了广义同步的数值模拟结果。     

一种超混沌PN序列的设计与实现

为了产生性能良好的伪噪声（PN）序列,基于一个新的超混沌系统,文中提出了一种超混沌PN序列的设计与实现方法,在对连续超混沌系统离散、量化的基础上,利用FPGA芯片实现了这种超混沌PN序列。通过一个串口通信模块电路采集了输出序列的全部样本并进行了序列性能分析,分析表明这种超混沌PN序列具有优良的随机特性和自相关特性,可用于扩频通信和信息加密之中。     

超混沌电路的参数调制控制研究

本文采用系统参数开关调制策略，研究了一个4D分段线性超混振荡器的控制问题，通过改变外部控制参数如调制幅度，可以把超混沌振荡器控制到不同的周期轨道，这种控制超混沌的方法为把超混沌振荡器应用于特殊的信号发生器或信号变换器提供了一种可能途径。     

一个超混沌Lorenz系统设计与FPGA电路实现

采用增加并改变系统非线性特性的方法对Lorenz系统进行变形,在此基础上,通过在三阶Lorenz系统中引入一个外加的状态变量构造了一个新的超混沌系统;对系统的一些基本特性,如耗散性、平衡点、稳定性进行了详细分析,系统超混沌的存在性通过Lyapunov指数谱得到了验证。还设计了一个数字电路进行实验,从电路实验中观察到了各种超混沌吸引子。     

基于Lorenz超混沌系统模糊渐近同步的保密通信系统

研究了一种基于Lorenz超混沌系统渐近同步的保密通信系统设计方法。首先采用T-S模糊模型对Lorenz超混沌系统进行精确描述,进而基于模糊混沌同步理论,利用Lorenz超混沌系统设计信号发射器和接收器,实现混沌保密通信。最后利用Matlab软件进行仿真研究。     

A hyperchaotic memristor oscillator with fuzzy based chaos control and LQR based chaos synchronization

Chaotic and hyperchaotic systems with interesting behaviors have been of interest in the recent years. In this paper we introduce a hyperchaotic memristor oscillator which shows both stable and unstable fixed points. Such systems have been less investigated in the literatures. It should also to be noted that the proposed hyperchaotic system has only one nonlinearity which is a flux controlled memristor. Depending on the control parameter, the system displays different behaviors and coexisting attractors. A linear quadratic regulator based synchronization of the proposed hyperchaotic system is designed and numerically analyzed. We also design such a fuzzy based PID controller for chaos control in such a memristor oscillator.     

被动调Q人眼安全内腔光学参量振荡器

利用被动调Q内腔光学参量振荡器动力学模型 ,求解了包含内腔光学参量振荡器的被动调Q速率方程 ,讨论了被动调Q内腔光学参量振荡器的动力学过程。实验上实现了被动调Q内腔光学参量振荡器运转 ,获得了脉宽小于 5ns ,能量大于 2 0mJ的 1 5 7μm人眼安全激光输出 ,通过改变OPO谐振腔输出镜的反射率 ,观测到输出单个和多个信号光脉冲现象 ,实验结果与理论分析相吻合。     

两个超混沌系统自动切换电路的设计和仿真

在一个四维二次超混沌系统的基础上,通过改变其中一个状态变量构造成一个新的超混沌系统,并且通过模拟开关自动切换状态变量,实现原超混沌系统和新的超混沌系统的自动循环切换。对新的超混沌系统的Lyapunov指数和分岔图进行了分析,通过数值仿真得到了相图;设计了一个模拟电子电路,电路仿真实验可以观察到两个超混沌系统自动切换的相图。仿真结果表明,该设计达到了较理想的效果。     

Controlling a unified chaotic system to hyperchaotic

This brief presents a simple technique using a sinusoidal parameter perturbation control input to drive a unified chaotic system to hyperchaotic. The original chaotic system is a three-dimensional autonomous system that has a broad spectrum of chaotic behaviors with the Lorenz and the Chen systems as two extremes of the spectrum. The control input is a simple sinusoidal function cos(/spl omega/t) with a constant parameter /spl omega/. The hyperchaotic system is not only demonstrated by computer simulations but also verified with bifurcation analysis and implemented via an electronic circuit.     

Bifurcation analysis of switched dynamical systems with periodically moving borders

This paper describes a method for analyzing the bifurcation phenomena in switched dynamical systems whose switching borders are varying periodically with time. The type of systems under study covers most of power electronics circuits where two or more dynamical systems are cyclically switched according to the interaction of the state variables and some periodically moving borders. In particular, the complex bifurcation behavior of a voltage feedback buck converter is studied in detail. The analytical method developed in this paper allows bifurcation scenarios to be clearly revealed in any chosen parameter space.