Adaptive controller design for full state hybrid projective synchronization of
uncertain hyperchaotic systems
Cong-xu Zhu
School of Information Science and Engineering
Central South University
Changsha, 410083, China
e-mail: zhucx@csu.edu.cn
Ke-hui Sun
School of Physics Science and Technology
Central South University
Changsha 410083, China
e-mail: kehui@csu.edu.cn
Abstract—In this paper, a simple adaptive control scheme is
developed to study the full state hybrid projective
synchronization (FSHPS) behavior between two identical
hyperchaotic systems with unknown parameters. The adaptive
FSHPS controllers are designed based on Lyapunov stability
theorem and an analytic expression of the controllers with the
adaptive laws of parameters are presented. The adaptive
controllers can be simplified ulteriorly such that it is not
necessary to exert controllers on all the variables to achieve
complete synchronization. The experimental results show that
parameters identification and FSHPS of two hyperchaotic
systems can be realized simultaneously. The proposed methods
have certain significance for reducing the cost and complexity
for controller implementation.
Keywords-Hyperchaotic system; adaptive control; parameter
identification; full state hybrid projective synchronization.
I. INTRODUCTION
Synchronization of one system with another is a very
important process in the control of complex physical,
chemical and biological systems. It can be applied to many
areas such as secure communication, chemical reactions,
biological systems, and information processing [1-3].
Therefore, many researchers have focused on this topic and
proposed various patterns of chaos synchronization from
different perspectives, such as complete synchronization [4],
phase synchronization [5], lag synchronization [6] and anti-
synchronization [7], etc. In 1999, Mainieri and Rehacek
proposed chaos projective synchronization, i.e. the
dynamical response systems can be synchronized to a scaling
factor [8]. Projective synchronization is unification of
different types of synchronization phenomenon, for example,
complete synchronization and anti-phase synchronization are
the special cases of generalized projective synchronization
respectively. In 2005, Wen et al. [9] presented a full state
projective synchronization (FSPS) between two dynamical
systems. In 2005, Hu et al. [10] presented a new form of
chaos synchronization, termed as full state hybrid projective
synchronization(FSHPS). The novelty feature of this
synchronization phenomenon is that the scaling factors can
be arbitrarily designed to different state variables by means
of control. Chu et al. [11] studied FSHPS problem between
two identical chaotic or hyperchaotic systems. But the
method presented in Ref. [10] and [11] can only deal with
the chaotic (hyperchaotic) systems with known parameters.
However, in practical engineering situations, parameters can
not be exactly known in priori and may change from time to
time. Therefore, there is a vital need to effectively full state
hybrid projective synchronize two chaotic or hyperchaotic
systems with unknown parameters. This is especially
important in theoretical research as well as practical
applications. In Ref. [12] Hu et al. studied the adaptive
FSHPS between Lorenz and Genesio chaotic systems,
hyperchaotic Chen and Lü systems, generalized Lorenz
system and Lorenz system, Lorenz system and hyperchaotic
Lü system. In Ref. [13] Wang et al. considered the adaptive
FSHPS between two identical unified chaotic systems. But in
Ref. [12] and [13] the authors fail to present identification of
parameters. In Ref. [14], Hu et al. investigated the problems
of parameters identification and the adaptive FSHPS
between two identical chaotic (hyperchaotic) systems with
full unknown parameters in drive systems, but the controller
is too complex.
To sum up, most of the previous researches on adaptive
FSHPS in chaotic systems were mostly focused on classical
chaotic systems. Furthermore, the controllers in these
existing FSHPS schemes are usually complex and difficult to
put into practice. In practical applications, the controllers to
realize synchronization must be simple, efficient and easy to
implement.
Motivated by the above discussion, in this paper, we
continue to investigate the FSHPS for a kind of chaotic
system. By constructing the idea of stabilizing sub-systems
respectively, the controller can be simplified, FSHPS
between two identical hyperchaotic systems with unknown
parameters can be realized, and parameters identification can
be achieved. Illustrative example is given to show the
effectiveness of this approach.
II.
GENERAL FORMULAE OF THE ADAPTIVE FSHPS
SCHEME
Suppose the drive and response systems are given in the
following forms, respectively:
2012 Fifth International Workshop on Chaos-fractals Theories and Applications
978-0-7695-4835-7/12 $26.00 © 2012 IEEE
DOI 10.1109/IWCFTA.2012.62
258
2012 Fifth International Workshop on Chaos-fractals Theories and Applications
978-0-7695-4835-7/12 $26.00 © 2012 IEEE
DOI 10.1109/IWCFTA.2012.62
267
2012 Fifth International Workshop on Chaos-fractals Theories and Applications
978-0-7695-4835-7/12 $26.00 © 2012 IEEE
DOI 10.1109/IWCFTA.2012.62
263