欠阻尼二阶线性系统中的随机共振及其抑噪应用

Stochastic Resonance of the Under-Damped Second-Order Linear System and Its Application in Noise Repression

在乘性噪声背景下,研究欠阻尼二阶线性系统中的随机共振及其抑噪应用.当二阶线性系统的阻尼系数和固有频率均受高斯白噪声干扰下,欠阻尼二阶线性系统中存在随机共振现象.研究表明,该系统的平均输出幅度增益呈现非单调变化,不仅在一定条件下大于无噪声时的增益,而且调节适当的系统参数和噪声强度能够提高幅度增益.因而只要使系统处于共振区域,就会使夹杂在噪声中的被测信号突现出来,从而实现弱信号的检测.因而,采用可视化仿真软件SIMULINK对此进行了实例模拟.仿真证实该方法检测弱信号的可行性和有效性.

This article detailedly studied stochastic resonance of the under-damped second-order linear system and its application in noise repression in the background of multiplicative noise.When damping coefficient and intrinsic frequency of the system are subject to Gaussian white noise,under-damped second-order linear system has the phenomenon of stochastic resonance.Research shows that the system presents the average output amplitude gain（OAG） under certain conditions. It not only is greater than when there is no noise second-order linear system,but also by adjusting the system parameters and noise intensity the output amplitude gain can be improved.So as long as the system is in the resonance region weak signal detection of under-damped second-order linear systems in the noise background can be achieved.Therefore,the article used visual simulation software SIMULINK to simulate some examples.The simulation confirmed that this method could detect the weak signal feasibly and effectively.