Research on Two Kinds of Adaptive Synchronization Method for Uncertain Fourth Order Chaotic Systems based on Sigmoid Function and Soft Function Method

Abstract

Synchronization of chaotic systems can be used in the secure communication so it greatly attracted interests of many researchers. The bounded characteristics of chaotic system was used and an uniformed adaptive law was designed to solve system uncertainties which make the whole design very simple. And two kinds of functions was used to take place of traditional sign function, then the chattering problem was greatly improved. A Lyapunov function was chosen to guarantee the stability of the whole design.At last, detailed simulation was done to show the rightness and effectiveness of the proposed method.