Detection of Weak Signal in Strong Noise Based on NBS Chaos System

Abstract

Based on the principle of chaos suppression with the piecewise periodic perturbation, detection of weak periodic signals in strong noise is realized with controlled NBS (Novel butterfly-shaped) model. First, according to the parametric equivalent relationship obtained using segment control mechanism, the parameter range is determined in different periodic states of the chaotic system. Second, combined with Lyapunov exponent criterion, the critical values of detection parameters are determined, which lead to a sudden change of the system dynamical behavior from chaotic state to periodic 3. Finally, the numerical simulation and the measured signals experiment are performed. The results show that the method reacts sensitively for weak signals, possesses the better inhibitory action on the noise, and can effectively improve the signal-to-noise ratio.