Frequency and Amplitude Identification of Weak Signal Based on the Limit System of Smooth and Discontinuous Oscillator

Abstract In this paper, a new method is proposed to identify the frequency and amplitude of weak signals by using non-smooth system. The variable scale limit system smooth discontinuous (SD) oscillator without considering phase adopted as identification By stochastic subharmonic-like Melnikov method, an analytical expression chaotic threshold under Gaussian white noise given. Based on diagram Poincaré section diagram, influence intensity recognition studied. According scale-convex-peak signal be detected can accurately identified. Using numerical simulation, measured identified according bifurcation reference signal. optimal value range parameters determined. Through example early fault wheelset bearing high-speed train, location determined, which verifies effectiveness above method. results show that submerged in strong noise, it has wider application higher accuracy than continuous