基于间歇混沌的微弱信号特征检测方法

A Method of Weak Signal Character Detection Based on Intermittent Chaos Moving

通过对Duffing振子的间歇混沌运动的分析,发现其相变对与参考信号频差较小的周期弱信号具有敏感性,对白噪声和与参考信号频差较大的周期干扰信号具有免疫力。在此基础上提出了一种检测方法,实现了在强噪声环境下对周期弱信号的频率和幅值的检测,具有很好的信噪比,并将其运用于超声波弱信号检测上,取得了良好的检测结果。

By analyzing the Duffing oscillator intermittent chaos moving, it is found that the Dulling oscillator phase transform is sensitive to the weak signal having the tiny angular frequency difference with the referential signal, and immune against the random noise and the larger interference signal having larger angular frequency difference with the referential signal. A mehod using the Duff- ing chaotic oscillator as the detection system was proposed, which is able to estimate the frequency and amplitude of weak sinusoidal signals, and gains a good SNR. The weak ultrasonic signal including large noise was detected. The result shows that this method is effective and successful.