基于线性反馈控制的超混沌系统设计与电路实现

基于最新提出的简化Lorenz混沌系统,采用线性控制策略,设计了一个超混沌系统。利用相图、Lyapunov指数谱、分岔图以及Poincaré截面分析方法,详细地研究了系统参数变化时简化Lorenz超混沌系统的动力学行为,数值仿真结果显示,Lyapunov指数谱与分岔图分析一致。采用分立元件,设计并实现了该系统的模拟电子电路,通过调节电路中的可变电阻,观察到了该系统的极限环、叉式分岔、倍周期分岔、混沌和超混沌,以及由倍周期分岔而进入混沌的道路等动力学现象。数值仿真和电路实验结果表明,该系统具有丰富的动力学特性,且电路实验结果与数值仿真相吻合。     

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。     

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。     

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。     

非线性电路系统动力学的研究进展及展望

介绍了非线性电路系统动力学几十年来的研究状况,重点阐述了几类典型的非线性电路,如蔡氏电路、“Jerk”电路和 DC-DC 变换器的研究进展.概括了非线性电路理论分析、数值模拟以及实验研究的主要方法,对目前非线性电路工作中的存在的一些问题和研究趋势进行了展望.     

文氏桥超混沌电路时滞反馈混沌控制

混沌镇定控制的应用范围很广,所采用的方法很多。本文研究了文氏桥超混沌电路的时滞反馈混沌镇定控制方法,利用模拟时滞反馈控制器将系统状态变量延时后接入原系统,实现了运行状态从超混沌态到单周期态的转变。设计了时滞反馈控制器电路,并进行了平衡点稳定性分析。电路实验结果验证了数值仿真结果,说明了时滞反馈控制器可以有效实现超混沌电路的混沌镇定控制。     

对一个新超混沌电路的研究

本文提出一种新的产生超混沌的电路。该电路非线性器件的选取不同于以往只局限于分段线性电阻的框框，而是采用分段线性负电容作为非线性元件。     

超混沌五阶自治电路的建模与仿真

提出了一个五阶自治混沌电路,基于电路建模与数值计算仿真对其混沌动力学性态和频谱分布特征进行了较详尽的研究。研究结果表明该电路在某些元件参数范围内,能够产生具有两个正性Lyapunov指数的超混沌信号,呈现出复杂的混沌动力学行为,将其用于保密通信,密文的抗破译强度会有较大的提高。     

VCSELs高阶分岔及混沌行为的参数控制

基于自发辐射在微腔激光器中的独特性,利用参数开关调制控制混沌的理论和技术,对VCSELs实施高频大信号深度调制和混沌控制的数值模拟.结果表明,提高自发辐射因子可抑制VCSELs的非线性行为,通过对自发辐射因子的开关调制,可把系统由混沌状态控制到平衡态和nP周期轨道,同时给出了VCSELS各种稳定周期态、分岔数、分岔点位置和混沌带与调控参数之间的定量关系.     

一种超混沌五阶自治电路的分析

在蔡式电路的L臂上增加一个RLC并联回路构造了一个超混沌五阶自治电路，对其进行数学建模和系统的理论分析，并结合数值仿真详细研究了其混沌动力学性态。通过对其相空间吸引子、庞卡莱映射、Lyapunov指数谱的分析表明，电路在参数值改变时，呈现出超混沌态、混沌态和周期态的振荡形式。最后对该电路从Hopf分叉变化到超混沌吸引子过程中的信号频谱进行了计算机模拟，估计其频谱分布范围并给出了电路的频谱分布特征。     

一种EDFA温控电路的分析

根据掺铒光纤放大器(EDFA)模块对泵源温度的严格要求,设计了一种双回路温控系统。该系统可使载体温度迅速达到给定的温度;通过微机的精确测温和对给定值的微调修正,使温控精度达到了±0.03～±0.05℃。     

一个新的四维混沌系统性质分析与电路实现

提出了一个新的四维混沌系统,并对该系统的基本动力学特性进行了分析,得到该系统的Lyapunov指数和Lyapunov维数,为验证这个混沌系统还设计了一个模拟电子电路,观察到了混沌吸引子,与仿真结果相符。     

Simulation study on hyperchaos analysis of reforming system based on single-ring erbium-doped fiber laser

A reforming dynamic system based on the single-ring erbium-doped fiber laser is proposed in this paper. The reforming system has larger Lyapunov exponent and better pseudorandom characteristics according to the simulation results. It is promising in the application of the image encryption and secret communication.     

Integrated Circuit Implementation of a Compact Discrete-Time Chaos Generator

A discrete-time chaos generator implemented with two nonlinear circuit cells has been fabricated in a 0.6 μm CMOS technology. Each cell is creating a function (map) which allows a chaos signal to be generated. Measurements of the chip were performed with a supply voltage of 5 V, up to a frequency of 2.5 MHz. A bifurcation diagram of the circuit and the Lyapunov exponent calculation are presented. The size of the generator layout (without the switches) is 32 × 19 μ m which makes it suitable for applications where many chaos signal generators are required on a single chip. Dan Juncu received the B.S. and M.Sc. degrees in Electrical and Electronics Engineering from the Technical University, Iasi, Romania in 1997 and 1998, respectively, and the Ph.D. degree in Electronics from UMIST, Manchester, UK in 2003. For his Ph.D. he did research on sensor interfaces for gas sensing devices; after that, he worked on RF IC on a new SiGe technology. In 2004 he joined Cambridge Consultants, Cambridge, UK. His current interests are in the area of switched capacitor filtering and computation, and sensor interfacing. Mandana Rafiei-Naeini received the B.Sc. degree in Electrical Engineering (majoring in Electronics) from Islamic Azad University of Tehran, Iran, in 2001 and the M.Sc. degree with distinction in Electronic Instrumentation Systems from University of Manchester in 2004. She is currently studying towards her Ph.D. degree in the School of Electrical and Electronic Engineering at The University of Manchester, working on clinical electrical impedance tomography systems for brain function imaging. She is a student member of IEE and IEEE. Piotr Dudek received his mgr in ż degree in electronic engineering from the Technical University of Gdańsk, Poland in 1997 and the M.Sc. and Ph.D. degrees from the University of Manchester Institute of Science and Technology (UMIST), Manchester, UK, in 1996 and 2000, respectively. He worked as a Research Associate at UMIST until 2002. Currently, he is a Lecturer in Integrated Circuit Engineering at The University of Manchester. His research interests are in analogue and mixed-mode VLSI circuits, smart sensors, machine vision, massively parallel processors, cellular arrays, bio-inspired engineering and spiking neural networks.     

Design and experimental confirmation of a novel switched hyperchaotic system

To generate complex pseudo-noise (PN) sequences for chaos-based communications, this article presents a novel switched hyperchaotic model, which is constructed based on a modified Chen system by introducing a dynamical controller. The system consists of two different hyperchaotic subsystems and can change its behavior randomly via a switching function. Basic dynamical behaviors of the hyperchaotic system are further investigated. Furthermore, the switched system is confirmed by its positive Lyapunov exponents and laboratory measurements by an electronic circuit.     

一种超混沌自动转换系统的设计与分析

在一种超混沌系统的基础上,通过改变系统第三个方程中的非线性项的方法,构造了一个新的超混沌系统,并利用常用开关函数来实现超混沌自动转换系统。通过matlab对超混沌系统进行仿真,产生超混沌吸引子,并对其子系统和转换系统Lyapunov指数进行分析与研究,仿真满足超混沌系统产生必要条件。结果表明所设计的自动转换系统可以实现两个超混沌系统的相互转换。