Engineering generalized synchronization in chaotic oscillators (original) (raw)

Generalized synchronization of chaotic oscillators

2006

The behavior of two unidirectionally coupled chaotic oscillators near the boundary of their generalized synchronization is analyzed. Using the modified system method, the position of this boundary on the plane of control parameters is considered and the physical mechanisms leading to the establishment of the generalized synchronization regime are elucidated.

Control of partial synchronization in chaotic oscillators

Pramana, 2015

A design of coupling is proposed to control partial synchronization in two chaotic oscillators in a driver-response mode. A control of synchrony between one response variables is made possible (a transition from a complete synchronization to antisynchronization via amplitude death and vice versa without loss of synchrony) keeping the other pairs of variables undisturbed in their pre-desired states of coherence. Further, one of the response variables can be controlled so as to follow the dynamics of an external signal (periodic or chaotic) while keeping the coherent status of other variables unchanged. The stability of synchronization is established using the Hurwitz matrix criterion. Numerical example of an ecological foodweb model is presented. The control scheme is demonstrated in an electronic circuit of the Sprott system.

Transitions from partial to complete generalized synchronizations in bidirectionally coupled chaotic oscillators

Physical review. E, Statistical, nonlinear, and soft matter physics, 2002

Generalized synchronization in an array of mutually (bidirectionally) coupled nonidentical chaotic oscillators is studied. Coupled Lorenz oscillators and coupled Lorenz-Rossler oscillators are adopted as our working models. With increasing the coupling strengths, the system experiences a cascade of transitions from the partial to the global generalized synchronizations, i.e., different oscillators are gradually entrained through a clustering process. This scenario of transitions reveals an intrinsic self-organized order in groups of interacting units, which generalizes the idea of generalized synchronizations in drive-response systems.

Enhancing synchronization in chaotic oscillators by induced heterogeneity

The European Physical Journal Special Topics

We report enhancing of complete synchronization in identical chaotic oscillators when their interaction is mediated by a mismatched oscillator. The identical oscillators now interact indirectly through the intermediate relay oscillator. The induced heterogeneity in the intermediate oscillator plays a constructive role in reducing the critical coupling for a transition to complete synchronization. A common lag synchronization emerges between the mismatched relay oscillator and its neighboring identical oscillators that leads to this enhancing effect. We present examples of one-dimensional open array, a ring, a star network and a two-dimensional lattice of dynamical systems to demonstrate how this enhancing effect occurs. The paradigmatic Rössler oscillator is used as a dynamical unit, in our numerical experiment, for different networks to reveal the enhancing phenomenon.

Targeting and Control of Synchronization in Chaotic Oscillators

International Journal of Bifurcation and Chaos, 2012

A method of targeting synchronization and its control is reported in chaotic oscillators. A design of appropriate coupling is proposed using an open-plus-closed-loop (OPCL) scheme based on Hurwitz stability to realize a desired state of synchrony between the oscillators. A general theory of the coupling definition is described for unidirectional as well as bidirectional mode. In a synchronization state, a chaotic attractor can be scaled up or down in size relative to another attractor. Additionally, a technique of controlling synchronization is introduced that allows a smooth transition from complete synchronization to antisynchronization or vice versa, by varying a parameter inserted in the coupling definition without loss of stability during the transition. A smooth scaling of the size of the attractor is also implemented. Numerical examples are given using a Sprott system. Physical realization of the OPCL coupling under bidirectional mode and control of synchronization under unid...

Fundamentals of synchronization in chaotic systems, concepts, and applications

1997

The field of chaotic synchronization has grown considerably since its advent in 1990. Several subdisciplines and ''cottage industries'' have emerged that have taken on bona fide lives of their own. Our purpose in this paper is to collect results from these various areas in a review article format with a tutorial emphasis. Fundamentals of chaotic synchronization are reviewed first with emphases on the geometry of synchronization and stability criteria. Several widely used coupling configurations are examined and, when available, experimental demonstrations of their success ͑generally with chaotic circuit systems͒ are described. Particular focus is given to the recent notion of synchronous substitution-a method to synchronize chaotic systems using a larger class of scalar chaotic coupling signals than previously thought possible. Connections between this technique and well-known control theory results are also outlined. Extensions of the technique are presented that allow so-called hyperchaotic systems ͑systems with more than one positive Lyapunov exponent͒ to be synchronized. Several proposals for ''secure'' communication schemes have been advanced; major ones are reviewed and their strengths and weaknesses are touched upon. Arrays of coupled chaotic systems have received a great deal of attention lately and have spawned a host of interesting and, in some cases, counterintuitive phenomena including bursting above synchronization thresholds, destabilizing transitions as coupling increases ͑short-wavelength bifurcations͒, and riddled basins. In addition, a general mathematical framework for analyzing the stability of arrays with arbitrary coupling configurations is outlined. Finally, the topic of generalized synchronization is discussed, along with data analysis techniques that can be used to decide whether two systems satisfy the mathematical requirements of generalized synchronization. © 1997 American Institute of Physics. ͓S1054-1500͑97͒02904-2͔

Chaotic synchronization of two complex nonlinear oscillators

Chaos Solitons & Fractals, 2009

Synchronization is an important phenomenon commonly observed in nature. It is also often artificially induced because it is desirable for a variety of applications in physics, applied sciences and engineering. In a recent paper [Mahmoud GM, Mohamed AA, Aly SA. Strange attractors and chaos control in periodically forced complex Duffing's oscillators. Physica A 2001;292:193-206], a system of periodically forced complex Duffing's oscillators was introduced and shown to display chaotic behavior and possess strange attractors. Such complex oscillators appear in many problems of physics and engineering, as, for example, nonlinear optics, deep-water wave theory, plasma physics and bimolecular dynamics. Their connection to solutions of the nonlinear Schrödinger equation has also been pointed out.