Experimental Research of Weak Signal Detection Method Based on the Dual-resonance

Abstract

The coupled bistable system is composed of two single bistable systems by means of nonlinear coupling. One of the bistable systems is controlled system which is subjected by the weak periodic signal, and the other is controlling system which is under the action of control signal. The dual-resonance characteristics of coupled bistable system under the controlling signal action were analyzed. When the frequency of control signal is twice of the weak periodic signal's frequency, the coupled bistable system can exist resonance in controlling system and stochastic resonance in controlled system, and a method based on dual-resonance to enhance stochastic resonance is proposed. A coupled bistable system hardware circuit system was designed based on dual-resonance. Experimental results confirm that there exists dual-resonance in coupled bistable system and the dual-resonance can enhance stochastic resonance greatly. Put the hardware circuit system into the detection of bearing fault signal, the power spectrum of coupling systems' output at the eigen frequency increase greatly, and it can detect weak signal of bearing fault effectively. A novel solution to detect the weak signal Based on the principle of stochastic resonance is provided, and it has a good application prospect.