摘要
噪声背景中周期信号的循环平稳性是信号处理中一个重要的特征。本文利用随机循环平稳过程的有关理论研究复杂随机动态系统中的随机共振现象。依据系统输出的一维准稳态概率密度近似理论,本文推导了系统输出二维跃迁概率密度、稳态自相关函数和系统输出信噪比的公式。输出信噪比随着输入噪声强度增加而呈现的随机共振现象,理论分析和数值试验结果非常吻合。此理论为随机共振理论的一种非绝热描述,不仅能够解释经典随机共振现象,而且能够描述驻留随机共振现象,对于复杂随机动态系统的信息处理机制具有重要理论指导意义。
The property of cyclostationarity is recognized to be of great importance to the signal processing community, This paper intends to show how the theory of stochastic cyclostationary processes can be used to study stochastic resonance in random dynamical systems. A two-dimensional transition probability and the stationary autocorrelation function are deduced from our previous work of a quasi-stationary probability density function. The output signal-to-noise ratio is then analytically represented as a non-monotonic function of input noise intensity. The theoretical results agree well with the numerical data, This theory is a kind of non-adiabatic description of stochastic resonance phenomena, including conventional stochastic resonance and residual stochastic resonance. Since the studying region of noise intensity is not restricted within weak region that is far smaller than unity, this theory of stochastic resonance may be of heuristic interest for exploring information processing mechanisms in complex random systems,
出处
《复杂系统与复杂性科学》
EI
CSCD
2007年第1期43-48,共6页
Complex Systems and Complexity Science
基金
教育部博士点联合资助基金(20051065002)
国家自然科学基金(60602040)
关键词
复杂随机系统
循环平稳性
随机共振
跃迁概率密度
稳态自相关函数
非绝热描述
complex random system
cyclostationarity
stochastic resonance
transition probability density
stationary autocorrelation function
non-adlabatlc description
