Research On Stochastic Resonance Equation Of Weak Beams Nonlinear Enhancement

Stochastic resonance has wide application in processing the signal which is overwhelmed by the noise, but how to design the reasonable nonlinear system and the pump based on different studied signals is critical on using stochastic resonance successful. In this paper, we obtain a new stochastic resonance equation on the stochastic resonance system in photorefractive ring cavity. The main achievements are as follow:1. In this paper, we have obtained the theoretical solutions or approximate theoretical solutions of two-wave mixing equation with fanning beams.In the previous work, it is usually to use the numerical solution on the two-wave mixing equation with fanning beams, as the same to the designing optimal parameter of nonlinear system. In this paper, we obtained the theoretical solutions of the pump, signal and fanning beams in the differential equation which has not absorption coefficient. Also, the approximate theoretical solution of the differential equation which has absorption coefficient has been studied. According to the theoretical solutions above, we can determine the optimal design of the system parameters.2. Improve the traditional stochastic resonance equation in the photorefractive ring cavity.Using the theoretical solutions above, we set up the new stochastic resonance equation in the photorefractive ring cavity and determine the optimal design of the system parameters. Comparing to the exiting stochastic resonance equation, the new one is more close to the true circumstance.3. We have simulated the application of the stochastic resonance equation on strengthening weak signals and verified the capability of system to increase the signal-to-noise(SNR) and the cross-correlation. The results demonstrate that this method could extract signals when signal is covering by noise, and the SNR gain could achieve about 10 dB and signal strength could be 6-7 times of the original signal strength.