Chin. Phys. B Vol. 21, No. 3 (2012) 030503
Adaptive projective synchronization of different chaotic
systems with nonlinearity inputs
∗
Niu Yu-Jun(Ú)
a)†
, Wang Xing-Yuan(,)
b)
, and Pei Bing-Nan(]H)
a)
a)
School of Information Engineering, Dalian University, Dalian 116622, China
b)
School of Electronic & Information Engineering, Dalian University of Technology, Dalian 116024, China
(Received 3 August 2011; revised manuscript received 25 September 2011)
We investigate the projective synchronization of different chaotic systems with nonlinearity inputs. Based on the
adaptive technique, sliding mode control method and pole assignment technique, a novel adaptive projective synchro-
nization scheme is proposed to ensure the drive system and the response system with nonlinearity inputs can be rapidly
synchronized up to the given scaling factor.
Keywords: projective synchronization, adaptive technique, sliding mode control, nonlinearity input
PACS: 05.45.Gg, 05.45.Xt, 05.45.Vx DOI: 10.1088/1674-1056/21/3/030503
1. Introduction
In 1990, Pecora and Carroll presented the con-
cept of ”chaotic synchronization” for the first time
[1]
and introduced a method to synchronize two identi-
cal chaotic systems with different initial conditions.
[2]
Nowadays chaotic synchronization has been inten-
sively studied.
[3−9]
Different types of chaotic synchro-
nization methods have been achieved, such as com-
plete synchronization, generalized synchronization,
phase synchronization, and lag synchronization.
[10−15]
In coupled partially linear systems, Mainieri and Re-
hacek reported that the two identical systems (drive
and response) could be synchronized up to a scaling
factor. This type of chaotic synchronization is referred
to as projective synchronization.
[16]
In applications
to secure communications, projective synchronization
can be used to extend binary digital to M-nary digi-
tal communication for achieving fast communication,
so projective synchronization has raised great concern
and been further studied.
[17−29]
For example, Xu and
Li
[17,18]
have presented the stability criterion of pro-
jective synchronization of three-dimensional chaotic
systems, the judge criterion of projective synchroniza-
tion of any dimensional continuous chaotic systems
and the necessary condition of projective synchroniza-
tion of any dimensional discrete chaotic system; the
projective synchronization technique has been applied
to chaotic secure communications.
[19−21]
Recently, by
Lyapunov stability theory, the adaptive control law
and the parameter update law have been derived
to make the states of two different chaotic systems
asymptotically synchronized up to a desired scaling
function.
[22]
Zhang and Lu
[28]
also extended the con-
cept of projective synchronization to the one of full
state hybrid projective synchronization in two differ-
ent chaotic systems. Hung et al.
[29]
have designed
the adaptive sliding mode controller to achieve the
projective synchronization of Chua’s systems with a
dead-zone in the control input. However, in the stud-
ies mentioned above and many other existing projec-
tive synchronization studies, the projective synchro-
nization of different chaotic systems and nonlinearity
input are not considered simultaneously.
In practical situations, in systems such as laser
array, biological systems and cognitive processes, it is
hardly the case that every component can be assumed
to be identical. In addition, in recent years, more
and more applications of chaos synchronization in se-
cure communications make it much more important
to achieve the projective synchronization of the two
different chaotic systems. In addition, in practical ap-
plications, owing to physical limitations, there always
exist nonlinear effects in the control actuators.
[30]
Ne-
glecting the effect of input nonlinearities usually re-
sults in degeneration of system performance.
∗
Project supported by the National Natural Science Foundation of China (Grant Nos. 60971107 and 60973152) and the Natural
Science Foundation of Liaoning Province, China (Grant No. 20082165).
†
Corresponding author. E-mail: yujun
−
niu@163.com
© 2012 Chinese Physical Society and IOP Publishing Ltd
http://iopscience.iop.org/cpb
http://cpb.iphy.ac.cn
030503-1