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Chua's Circuits (chua + circuit)

Distribution by Scientific Domains

Engineering	100%

Selected Abstracts

Some new algebraic criteria for chaos synchronization of Chua's circuits by linear state error feedback control

INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 3 2006
Xiaofeng Wu
Abstract The research on the sufficient criterion for chaos synchronization of the master,slave Chua's circuits by linear state error feedback control has received much attention and some synchronization criteria for special control matrix were proposed. In this paper, the above synchronization issue is investigated in the situation of general linear state error feedback controller with propagation delay of control signals from the master Chua's circuit. First of all, a master,slave synchronization scheme for Chua's circuits with propagation delay is given and the relevant error system is derived. Using a quadratic Lyapunov function and frequency domain method, three new algebraic synchronization criteria for the synchronization scheme with general control matrix are proven. They are applied to derive the synchronization criteria for simple control matrices. Some examples are given to show the sharpness of these new criteria compared with the known criteria. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Hyperchaotic behaviour of two bi-directionally coupled Chua's circuits

INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 6 2002
Barbara Cannas
Abstract In this paper, a non-linear bi-directional coupling of two Chua's circuits is presented. The coupling is obtained by using polynomial functions that are symmetric with respect to the state variables of the two Chua's circuits. Both a transverse and a tangent system are studied to ensure a global validity of the results in the state space. First, it is shown that the transverse system is an autonomous Chua's circuit, which directly allows the evaluation of the conditions on its chaotic behaviour, i.e. the absence of synchronization between the coupled circuits. Moreover, it is demonstrated that the tangent system is also a Chua's circuit, forced by the transverse system; therefore, its dynamics is ruled by a time-dependent equation. Thus, the calculus of conditional Lyapunov exponents is necessary in order to exclude antisynchronization along the tangent manifold. The properties of the transverse and tangent systems simplify the study of the coupled Chua's circuits and the determination of the conditions on their hyperchaotic behaviour. In particular, it is shown that hyperchaotic behaviour occurs for proper values of the coupling strength between the two Chua's circuits. Finally, numerical examples are given and discussed. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Reconstruction of chaotic signals with application to channel equalization in chaos-based communication systems

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 3 2004
Jiuchao Feng
Abstract A number of schemes have been proposed for communication using chaos over the past years. Regardless of the exact modulation method used, the transmitted signal must go through a physical channel which undesirably introduces distortion to the signal and adds noise to it. The problem is particularly serious when coherent-based demodulation is used because the necessary process of chaos synchronization is difficult to implement in practice. This paper addresses the channel distortion problem and proposes a technique for channel equalization in chaos-based communication systems. The proposed equalization is realized by a modified recurrent neural network (RNN) incorporating a specific training (equalizing) algorithm. Computer simulations are used to demonstrate the performance of the proposed equalizer in chaos-based communication systems. The Hénon map and Chua's circuit are used to generate chaotic signals. It is shown that the proposed RNN-based equalizer outperforms conventional equalizers as well as those based on feedforward neural networks for noisy, distorted linear and non-linear channels. Copyright © 2004 John Wiley & Sons, Ltd. [source]

Hardware implementation of CNN architecture-based test bed for studying synchronization phenomenon in oscillatory and chaotic networks

INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 4 2009
Ákos Tar
Abstract A 3D modular cellular nonlinear network (CNN) architecture-based test bed, with four-neighbor connectivity, used to study synchronization phenomena in oscillatory and chaotic networks is designed. The architecture is implemented as hardware panels including a standalone robust Chua's circuit kit. The details of electronic implementation along with several test cases of connecting Chua's circuits in different topologies are provided. Test cases are adequately supported by oscilloscope traces. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Some new algebraic criteria for chaos synchronization of Chua's circuits by linear state error feedback control

Hyperchaotic behaviour of two bi-directionally coupled Chua's circuits

Controlling Chua's circuits using computational verb controllers

INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 17 2008
R. Tonelli
Abstract In this paper, computational verb controllers were used to control Chua's circuits that were chaotic. The computational verb rule-wise linear models of Chua's circuits were used to approximately segment the dynamics of Chua's circuits into four qualitatively different clusters; namely, the dynamics in the inner region, in the outer region and at boundaries of both regions. Then the stable verb controllers were designed by using linear matrix inequalities. Simulation results are presented to show the soundness of the design method. Copyright © 2008 John Wiley & Sons, Ltd. [source]