乘性噪声作用下线性系统的随机共振及其抑噪应用

Stochastic resonance of linear system with multiplicative noise and its application repress noise

在二阶线性系统的阻尼系数和固有频率同时受一类乘性噪声干扰下,详细研究利用欠阻尼二阶线性系统中的随机共振消除此类噪声。研究表明,当二阶线性系统的固有频率和被测信号均受乘性高斯白噪声干扰下,欠阻尼二阶线性系统中存在随机共振现象,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,从而实现信号的检测。采用可视化仿真软件SIMULINK对此进行了实例模拟。仿真证实了该方法消除乘性噪声的可行性和有效性。

This article studied the use of stochastic resonance of the under-damped second-order linear system to reduce the multiplicative noise.Research shows that when intrinsic frequency and input signal of the system are subject to multiplicative Gaussian white noise,under-damped second-order linear system shows the phenomenon of stochastic resonance.The average output amplitude gain（OAG） is non-linear and under certain conditions the value is greater than that of no noise second-order linear system,and proper adjustment of the system parameters and noise intensity can improve the output amplitude gain.So as long as the system is in the resonance region,weak signal detection of under-damped second-order linear systems can be fulfiled in the noise background.The article used visual simulation software SIMULINK to simulate some examples.Simulation confirmed that this method resolveds multiplicative noise feasibly and effectively.