一种Duffing弱信号检测新方法及仿真研究

研究了利用混沌相变进行弱信号检测的理论及仿真试验.对基于Duffing振子初值敏感性检测弱信号的方法分析后指出，过渡过程会影响检测性能，提出一种改进的弱信号检测方法.对仿真输入噪声生成和仿真步长选择进行研究后建立了仿真模型，在典型噪声背景下检测弱正弦信号.实验结果表明：所提出的方法有较好检测性能；混沌临界态的Duffing系统对噪声敏感导致相变方法难以精确确定最小检测幅值.指出了这类方法的局限性. 关键词： 混沌 信号检测 周期信号 白噪声

A new method of weak signal detection using Duffing oscillator and its simulation research

The theory and simulation technique of weak signal detection using chaos state phase change is researched in this paper. The method of weak signal detection by using the Duffing oscillator's initial conditions sensitivity was firstly analyzed， the existing transition process would affect the detection capability. Then an improved method was presented. In order to compare these two methods， the input pseudo-noise expression and the calculating step selection in simulation were researched， and the simulation models were established. The new method was shown to have better capability through analyzing the signal detection experimental results under the condition of typical noise intensity background. The experiments showed that the Duffing oscillator in special critical chaos state is also sensitive to noise， which leads to the difficulty in exactly deciding the minimal detection limit by phase change， and the limitation of the phase change method was discussed.