在振动共振的基础上,研究了非线性单稳随机共振系统在高、低两种不同频率作用下的动力学特性,分析得出高频信号可以使系统产生分岔,而低频信号幅值及单稳系统非对称参数是系统跃迁阈值的影响因素,调节高、低频信号参数可改变势垒高度,诱发单稳随机共振效应.理论分析和数值仿真结果表明,在绝热近似条件下,单稳随机共振系统输出信号的信噪比及功率谱均呈非单调变化,同时通过级联后单稳系统输出的效果更佳,冲击信号仿真分析表明该类型随机共振系统有利于工程实际.
On the basis of vibration resonance, the dynamic characteristics of the non-linear monostable system subject-ed to the action of high and low frequency signals were studied. Analysis indicates that the high frequency signal can cause system bifurcation, and the amplitude of low frequency signal and the asymmetric parameter of monostable system are the influence factors of the threshold of system transition. Adjusting the parameters of high and low frequency signals can change the height of potential barrier, and induce the effect of monostable stochastic resonance. Theoretical analysis and the results of numerical simulation show that under the adiabatic approximate condition, the SNR and PSD of output signal of the monostable system vary non-monotonically. Meanwhile, better output signal of cascaded monostable system can be ob-tained. The simulation of impact signal shows that this kind of stochastic resonance system is useful in engineering applica-tions.