共查询到20条相似文献,搜索用时 135 毫秒
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对Pecora和Carroll的混沌自同步方案的延迟同步误差进行了研究.在计算机上对Lorenz混沌系统伪装的延迟同步误差进行了模拟:给定系统参数,对应不同延迟时间,得出了均方误差与采样步长的关系曲线;给定系统参数和延迟时间,对应不同采样步长,得到了混沌时间序列的误差曲线;给定采样步长,对应不同的系统参数,获得了混沌时间序列的尺度效应和均方误差与采样步长的关系曲线.提出了减小延迟同步误差的一些方法,得到一些对混沌同步和混沌控制应用有意义的结果.
关键词:
混沌同步
时间同步
误差分析 相似文献
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针对一种新型的双路激光混沌复用系统, 建立相应的速率方程模型, 详细分析了两个主激光器的单个参数失配、多个参数同时失配、反馈强度差异以及频率失谐对混沌同步性能的影响, 并对此复用系统的安全性能和频谱性能进行了研究. 研究结果表明: 采用参数失配方案, 通过合理选择两个主激光器的参数, 可以保证两个主激光器之间的同步性能较差而两对主从激光器间实现高品质的混沌同步, 因此满足双路激光混沌复用的条件; 两个主激光器之间的参数失配对它们之间的同步性能影响较大, 然而对配对主从激光器间同步性能的影响并不明显, 进一步说明参数失配方案的有效性和可行性. 另外, 通过自相关函数和频谱分别分析混沌复用信号的时域和频域特征, 发现双路激光混沌复用系统可提供更高的安全性. 相似文献
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The resistively--capacitively--inductively-shunted (RCL-shunted)
Josephson junction (RCLSJJ) shows chaotic behaviour under some
parameter conditions. Here a scheme for controlling chaos in the
RCLSJJ is presented based on the linear feedback theory. Numerical
simulations show that this scheme can be effectively used to control
chaotic states in this junction into stable periodic states.
Moreover, the different stable period states with different period
numbers can be obtained by appropriately adjusting the feedback
intensity and delay time without any pre-knowledge of this system
required. 相似文献
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The resistively-capacitively-inductively-shunted (RCL-shunted) Josephson junction (RCLSJJ) shows chaotic behaviour under some parameter conditions. Here a scheme for controlling chaos in the RCLSJJ is presented based on the linear feedback theory. Numerical simulations show that this scheme can be effectively used to control chaotic states in this junction into stable periodic states. Moreover, the different stable period states with different period numbers can be obtained by appropriately adjusting the feedback intensity and delay time without any pre-knowledge of this system required. 相似文献
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Chaos in the dc and rf current driven Josephson junction is investigated by measurements on a phase-locked loop. The method allows a direct display of the Poincaré map and the bifurcation diagram, as the parameter space is searched. In some regions of the parameter space the Feigenbaum period-doubling route to chaos is observed upon a change of any parameter. 相似文献
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Lai YC Kandangath A Krishnamoorthy S Gaudet JA de Moura AP 《Physical review letters》2005,94(21):214101
We propose a scheme to induce chaos in nonlinear oscillators that either are by themselves incapable of exhibiting chaos or are far away from parameter regions of chaotic behaviors. Our idea is to make use of small, judiciously chosen perturbations in the form of weak periodic signals with time-varying frequency and phase, and to drive the system into a hierarchy of nonlinear resonant states and eventually into chaos. We demonstrate this method by using numerical examples and a laboratory experiment with a Duffing type of electronic circuit driven by a phase-locked loop. The phase-locked loop can track the instantaneous frequency and phase of the Duffing circuit and deliver resonant perturbations to generate robust chaos. 相似文献
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The chaotic behaviours in the p--Ge photoconductor system
are studied by changing the photo-excitation coefficient and the
routes and parameter conditions are given for chaos generation in
this system. A scheme for controlling chaos in the p--Ge
photoconductor is presented by adding an ac bias current. Numerical
simulations show that this scheme can be effectively used to control
chaotic states into stable period states for this system. Moreover,
the different period states with different period numbers can be
obtained by appropriately adjusting the amplitude, frequency, and
initial phase of the additional ac current. 相似文献
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In this paper, we apply an iterative parameter adaption scheme based on chaos synchronization to estimate system parameters of the asymmetric vocal folds from glottal area time series. The original asymmetric vocal-fold system associated with recurrent laryngeal paralysis shows chaotic vibrations with positive Lyapunov exponents. Aperiodic glottal area time series from the original system will be applied as the feedback variable coupling the simulative and the original vocal-fold systems. The parameter adaption technique based on chaos synchronization is employed to manipulate the simulative system parameters. The chaotic vibrations, system parameters, and the bifurcation diagram of the original vocal-fold system can be exactly reproduced in the simulative system, and the two chaotic systems can be synchronized. Furthermore, the effects of noise, sampling rate, and equation difference due to nonlinear spring terms on vocal-fold parameter estimations are investigated. Despite large noise perturbations, large equation differences, and low sampling rate, the parameter adaption scheme can effectively estimate the original vocal-fold system parameters. This study provides a theoretical base to apply chaos synchronization to estimate the vocal-fold system parameters from the glottal area data and show its potential application in laryngeal physiology. 相似文献
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Spatiotemporal communication with synchronized optical chaos 总被引:2,自引:0,他引:2
We propose a model system that allows communication of spatiotemporal information using an optical chaotic carrier waveform. The system is based on broad-area nonlinear optical ring cavities, which exhibit spatiotemporal chaos in a wide parameter range. Message recovery is possible through chaotic synchronization between transmitter and receiver. Numerical simulations demonstrate the feasibility of the proposed scheme, and the benefit of the parallelism of information transfer with optical wave fronts. 相似文献
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Zambrano S Allaria E Brugioni S Leyva I Meucci R Sanjuán MA Arecchi FT 《Chaos (Woodbury, N.Y.)》2006,16(1):013111
A well-known method to suppress chaos in a periodically forced chaotic system is to add a harmonic perturbation. The phase control of chaos scheme uses the phase difference between a small added harmonic perturbation and the main driving to suppress chaos, leading the system to different periodic orbits. Using the Duffing oscillator as a paradigm, we present here an in-depth study of this technique. A thorough numerical exploration has been made focused in the important role played by the phase, from which new interesting patterns in parameter space have appeared. On the other hand, our novel experimental implementation of phase control in an electronic circuit confirms both the well-known features of this method and the new ones detected numerically. All this may help in future implementations of phase control of chaos, which is globally confirmed here to be robust and easy to implement experimentally. 相似文献
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T. Deng H. T. Chen X. D. Lin Y. Y. Xie J. G. Wu G. Q. Xia Z. M. Wu J. G. Chen 《Laser Physics》2012,22(11):1667-1672
In this paper, a bidirectional chaos secret communication system, based on mutually coupled semiconductor lasers (MCSLs) with asymmetrical bias currents, is proposed, and the synchronization characteristics and the communication performances of such a system are numerically investigated. The results show that the stable leader-laggard chaos synchronization can be achieved under relatively large asymmetrical bias current levels. Meantime, the influence of the intrinsic parameter variations of the laser on the synchronization quality is also considered, and the simulation reveals that this system still possesses good robustness to the parameter variations. Moreover, the influences of delay time and mutually coupling strength between the two lasers on chaos communication performance have also been discussed. Finally, unidirectional and bidirectional secret communication performances of such a system are examined under the chaos masking (CMS) encryption scheme, and the security of this system is also discussed. 相似文献
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We investigate the effects of external current noise on a microwave-driven Josephson junction. We show that the circle return map for the superconducting phase difference is stable with respect to the external noise and find that the effects of fluctuations on the route to chaos described with the circle map can be opposite to those for the Feigenbaum period-doubling cascade: increasing noise can here act as a control parameter triggering a periodically oscillating junction chaotic by generating an inflection point in the return (circle) map. This may prove important also for other physical systems, including charge density waves. 相似文献