Stochastic Resonance Mechanisms In Several Nonlinear Systems

Stochastic resonance is one of the novel methods among many signal processing methods.It makes reasonable use of noise,makes noise play an active role in the signal detection process,amplifies the characteristics of the signal,and greatly facilitates signal detection and fault diagnosis.Since stochastic resonance was proposed,it has been widely used in various fields,and related research is also of great significance.This paper mainly studies the stochastic resonance mechanism in nonlinear systems excited by chirp signals and nonlinear systems driven by unilateral attenuated impulse signals.The main contents are as follows:Chapter 1,briefly introduces the research background of this paper and the current domestic and foreign research status of the research object and introduces the research content,innovation points and preliminary knowledge.Chapter 2,monostable systems and multistable systems excited by chirp signals are established.Discuss the influence of system potential function changes on stochastic resonance,compare and analyze the stochastic resonance phenomena in the two systems,and further study the stochastic resonance changes in the two types of systems under the change of chirp signal parameters and multiple chirp signals.Chapter 3,based on the particle swarm optimization algorithm and its variant algorithms,the algorithm for inducing stochastic resonance of two types of systems with adaptive parameters is studied.Chapter 4,a second-order underdamped system excited by a chirp signal is established,and the influence of different system parameters and signal parameters on the stochastic resonance phenomenon of the system is studied.Chapter 5,a fractional order system driven by a unilateral attenuated impulse signal is established,and the stochastic resonance behaviour and its variation with parameters are discussed from a theoretical point of view.The results of numerical experiments demonstrate the amplification effect of stochastic resonance on signal faults.Chapter 6,summarizes the article and looks forward to future research.