Research on multi-frequency weak signals detection method based on bistable vibrational resonance

摘要

Considering the nonlinear bistable vibrational resonance(VR) system, the mean signal-noise-ratio gain(MSNRI) is taken as performance index and VR phenomenon subjected to the action of high and low frequency signals is studied under α stable noise. Then the action laws between the amplitude B and frequency Ω of a high frequency drive signal on the resonant output effect is explored. Finally, the multi-high frequency weak signals detection(w_i 1Hz) with a stable noise can be realized combing with the method of twice sampling. Results show that in bistable VR system, when a (or β) is given different values, the curve of MSNRI-B has multiple peaks with B increasing for a determined Ω, and the intervals of B which can induce VRs are multiple. Similarly, the same conclusion can be obtained from the curve of MSNRI-Ω for a determined B. Besides, the resonance intervals of B and Ω don't change with a or β. The above conclusions lay a foundation for realizing multi-frequency weak signals detection of the industrial sites using bistable VR theory, which have potential applications in sign.al processing.