Weak Signal Detection Based on Improved Double-Coupled System and Section Variance Method

In this paper, a weak signal detection method based on improved double-coupled system and section variance method is proposed. We change the coupling mode of Duffing oscillator and Van Der Pol-Duffing oscillator to obtain higher initial sensitivity and better detection performance. In addition, we also put forward the section variance method to discriminate the system state. The degree of dispersion of the points on the system phase diagram section is taken as an index to measure the degree of chaos of the system and make state discrimination. Due to the simple operation, the section variance method can quickly and accurately discriminate the system state. In this paper, the weak sinusoidal signal and chirp signal are detected respectively to verify the superiority of the proposed detection method. Simulation results show that the detection method perform well at low SNR.