延迟双稳系统中乘性和加性噪声诱导的随机共振

在双稳系统基础上,基于随机共振(SR)理论,研究非对称双值噪声、方波信号以及乘性和加性噪声驱动的延迟双稳系统中噪声强度、噪声相关时间、方波幅度对系统输出信噪比(SNR)的影响.在绝热极限条件下,利用小延迟近似,得到系统输出信噪比的表达式,给出SNR随噪声强度、噪声相关时间以及方波信号幅度的变化曲线.结果表明,SNR与双值噪声的强度和非对称性、与乘性和加性噪声的强度以及与方波信号的幅度关系都表现出SR现象.SNR随延迟时间、色噪声的相关时间及系统参数的变化而非单调变化.

Stochastic resonance induced by multiplicative and additive noise in time-delayed bistable system

Based on a bistable system, the effect of noise intensity, noise correlation time, the amplitude of a square-wave signal for a time delayed bistable system, driven by an asymmetric dichotomous noise, the square-wave signal, as well as by additive and multiplicative noise, on the system output signal-to-noise ratio (SNR) was analyzed by applying the stochastic resonance (SR) theory. Under the adiabatic limit condition, the expression of the SNR of the system was obtained by using the small delay-time approximation. The curves of the output SNR as a function of the noise strength, noise correlation time, and the amplitude of the square-wave signal were plotted. Results show that the SNR curves present SR phenomenon as a function of the intensity and asymmetry of dichotomous noise, of the strength of the multiplicative and additive noise, as well as of the amplitude of the square wave. In addition, the SNR varies non-monotonously with the delayed-time, with the correlation time of the colored noises and with the system parameters.