Study On Stochastic Facilitation Of Noise And Its Application

Stochastic facilitation disccribe noise benefits in the nonlinear system. It involves the signal, noise and the nonlinear system. The noise intensity and frequence are given in the circumstance of practical application. While by changing the potential function can change the nonlinear characteristics of the system, the effect of stochastic facilitation caused by noise can be enhanced. The facilitation effects of noise in different nonlinear systems are analyzed by adopting the combination of approximate analytical theory and numerical simulation method The quadratic segmented bistable potential function and the weak signal detection method based on quadratic segmented bistable system stochastic facilitation are put forward.The output characteristic of classic bistable potential function is analyzed. Based on the saturation characteristics of the boundary function caused by high power, the quadratic segmented bistable potential function is proposed. The Kramer’s escape rate and output SNR of the potential function is derived theoretically. The numerical simulation proves it can improve the signal-to-noise ratio of the output signal and power spectrum, and it also can enhance the effect of stochastic facilitation caused by noise. From the angle of dynamics, the influence of the potential field force effect on the facilitation effects of noise is studied.By analyzing the changes of the system output signal amplitude when the different amplitude of the sinusoidal periodic signals act on the quadratic bistable system separately, the unsaturated features of the system have been explained. And the static triggering threshold value of the input signal in the quadratic segmented bistable system is given. The output characteristics in a quadratic segmented bistable system under different noise intensity and a sinusoidal periodic signal with the same amplitude are analyzed. It turns out that the form of the potential function can affect the stochastic facilitation caused by noise.Respectively, the theory of quadratic segmented bistable system stochastic facilitation method is applied to the bearing fault signal detection and the vortex flow signal detection. The experimental results show that the weak signal detection method based on quadratic segmented bistable system stochastic facilitation is effective, and it also can enhance the effect of stochastic facilitation caused by noise.Finally, a weak signal detection oftware based on quadratic segmented bistable system stochastic facilitation have been developed. It takes advantage of MATLAB Scrip node for a mixture of Lab VIEW and MATLAB programming. The detection of vortex signal shows that the software can be applied to the actual weak signal detection.