一个广义Hamilton系统的混沌特性及电路实现

Chaotic Behavior of a Generalized Hamiltonian System and Its Circuit Implementation

以广义Hamilton系统为基础,通过增加耗散量和外部输入,形成广义耗散Hamilton系统。通过配置广义耗散Hamilton系统的结构矩阵和外部输入,提出一个简单三维单平衡点系统来说明此类系统存在混沌行为。借助相图、庞加莱截面、Lyapunov指数谱、分形图和功率谱等数值分析方法说明当外部输入逐步增强时该系统存在周期轨道和混沌运动。与一般已知的三维混沌系统相比,该系统的特点为:耗散性与系统的状态变量相关;处于混沌状态时的系统的Lyapunov维数接近3。最后设计了该系统的实验电路,示波器观测到的实验结果进一步验证了该系统确实存在混沌行为。

A kind of generalized Hamiltonian systems with dissipative structure and external input is proposed.By configuring its structure matrix and external input,a simpler three-dimensional dynamical system with only one fixed point is designed to illustrate the existence of chaos.Useful tools,including phase portrait,Poincarésection,Lyapunov exponents,bifurcation diagram and power spectrum,are used for detecting chaotic behavior of the proposed system with the enhancement of DC input.Compared with the known three-dimensional chaotic systems,the proposed system has the following two characteristics:Its dissipativity is related to system state variables and its Lyapunov dimension is closer to 3.Finally,a circuit implementation of the new system is presented and the results recorded on an analogue oscilloscope further verify the existence of chaotic behavior.