Research on Weak Signal Detection by Adding Noise to Cascaded Stochastic Resonance Step by Step

In view of the fact that after excitated by weak signal under background of noise the action of transition between potential wells of bistable system cannot occur or occasionally happen, this paper puts forward a method of weak signal detection by adding noise to cascaded stochastic resonance step by step. In this method the output signal of the former bistable system whose transition between potential wells occasionally occurs is converted into a local oscillation within an unilateral potential well step by step, then DC component is removed, a moderate intensity of Gaussian color noise is stacked and then by utilizing energy transfer functions of bistable system, gradually the signal is enabled to overcome the critical value of the latter bistable system and transition of frequency synchronization between potential wells is produced for signals to be tested. The simulation results of weak sinusoidal signal and periodic impact signals detected under the background of noise show the feasibility of this method.