Effect of Positive Feedback With Threshold Control on Stochastic Resonance of Bi-Stable Systems

It is important to magnify natural stochastic resonance of nonlinear systems. In this paper, positive feedback is proposed to enhance stochastic resonance of those nonlinear systems whose internal parameters are difficult or impossible to be adjusted. The method can be used to improve the response of these nonlinear systems to external stimulus or strengthen the effect of target manipulation. At first, theoretical analysis based on adiabatic approximation method is presented, and then numerical simulations for both hard potential system and soft potential system are conducted to demonstrate the proposed method. Both theoretical analysis and numerical simulation indicate that stochastic resonance of these systems can be magnified by positive feedback.