关联噪声驱动的非对称双稳系统的随机共振

运用统一色噪声近似理论和两态模型理论，研究了周期矩形信号和关联的乘性色噪声和加性白噪声驱动的非对称双稳系统的随机共振现象，得到了适合信号任意幅值的信噪比表达式.信噪比是乘性噪声强度、加性噪声强度、乘性噪声自关联时间、噪声耦合强度的非单调函数，所以该双稳系统中出现了随机共振.同时，调节加性噪声强度比调节乘性噪声强度更容易产生随机共振.势阱静态非对称性和噪声之间的耦合强度对信噪比的影响是不同的. 关键词： 非对称双稳系统 随机共振 信噪比 周期矩形信号

Stochastic resonance in an asymmetric bistable system driven by correlated noise

The phenomenon of stochastic resonance (SR) in a bistable system subject to correlated multiplicative colored and additive white noises and a periodic rectangular signal with a constant component is investigated in the unified colored noise approximation and by applying the two-state theory. The expression of the signal-to-noise ratio (SNR) is obtained for arbitrary signal amplitude. The SNR is a non-monotonic function of intensities of multiplicative colored and additive white noises，correlation time of multiplicative colored noise and the strength of the coupling between noises， so SR appears in the bistable system. Meanwhile， it is more effective to control SR through adjusting the additive white noise intensity than adjusting the multiplicative colored noise intensity. Moreover，the effects of potential asymmetry and the strength of the coupling between noises on SNR are opposite.