过阻尼非线性系统抑制大频率噪声机理及其弱信号检测研究

Study on the mechanism of restraining large frequency noise and its application of weak signal detection of over-damped nonlinear system

文章应用四阶Runge-Kutta算法对非线性Langevin方程进行分析,研究过阻尼非线性双稳态系统抑制噪声效应机理和大频率弱信号通过非线性双稳态系统的输出特性.数值计算结果表明,在选择适当系统参数的条件下,过阻尼非线性双稳态系统对伴随大频率弱信号的噪声具有强烈的抑制作用,使得输出信号的信噪比明显提高.将该系统用于强噪声背景下的弱信号检测,达到了识别大频率弱信号的目的,具有较高的应用价值.

The mechanism of noise restraint effect of over-damped nonlinear bistable system and the out-put characteristic of large frequency weak signal passing through nonlinear bistable system are studied in this paper by using the fourth order Runge-Kutta algorithm to analyze the nonlinear Langevin equation.The results of numerical calculation show that nonlinear bistable system has the effect of restraining noise going with large frequency weak signal intensively under the situation of choosing system parameters properly,consequently,the signal-to-noise ratio of output signal is improved evidently.The purpose of extracting large frequency weak signal is achieved by applying this system to detect weak signal from heavy noise background,and this system has been of high applying value.