Study On Stochastic Resonance Induced By Dichotomous Noise In Periodic Potential System

Stochastic Resonance(SR) and its telated problems have become an important research subject in nonlinear dynamics for its great prospects in weak signal detection, and the discovery of SR has changed people’s perception of the noise. Periodic potential system is a widely used system. Many engineering systems, electronic circuit, superconducting devices are based on periodic potential system, and dichotomous is a typical model of real noise. This thesis studies the dynamical behaviors and the SR in periodic potential systems driven by dichotomous noise. The main work and conclusions are as follows:1. The SR is studied in the overdamping periodic potential system subject to not correlated additive white noise and multiplicative dichotomous noise. The steady-state probability density function is obtained by using the Fokker-Planck equation. SR is measured with the change of amplitude of the average output signal. It is found that, when the additive white noise intensity and noise autocorrelation are fixed, SR can occur as the increase of multiplicative dichotomous noise intensity, and the intensity of additive white noise has a significant effect on the SR.2. The dynamical behaviors and SR are studied in the underdamping periodic potential system driven by periodic signal and dichotomous noise. And SR is measured by stochastic energetics and signal to noise ratio(SNR). It is found that, the width of the stochastic resonance region will increase as the increase of the correlation time of dichotomous noise and the asymmetry coefficient of system, it is easier to generate SR for the dichotomous noise compared to Gauss white noise. Moreover, the maximum value of the stochastic resonance are different by using the stochastic energetics and SNR.3. The SR is studied in the periodic potential system subject to mixed periodic signal and correlated additive and multiplicative dichotomous noise. We discussed the influence of intensity of additive and multiplicative dichotomous noise, correlation coefficient, and the mixed periodic signal amplitude and phase on the SR. It is found that, when other parameters remain unchanged, the change of additive and multiplicative noise intensity can lead to SR. Therefore, the difference of correlation coefficient of additive and multiplicative dichotomous noise is nearly no influence on SR.