Study On The Weak Signal Detection Approaches Based On Duffing Chaotic System

Weak signal detection (WSD) is one of the important content in the area of information process, it is an important approach for human to get the useful information. Weak signal measurement has widely applied in radar, sonar technology, vibration measurement, trouble diagnosis, communication, physics, system identification and other fields. With the development of science technology, the needs of WSD becoming increasingly urgent. WSD is an important way to improve advanced technology, to explore and find natural law. It have great significance for the promotion in the relative area. The weak signal have the very small amplitude, very low signal noise ratio(SNR), the signal to be measured is often covered by noise. The traditional signal detection method can't satisfy the WSD. The chaotic theory brought the new breakthrough to WSD, the accurate of the WSD was improved.This article introduced the characteristic and the definition of chaotic theory, and the theory about chaotic attractor. Discussed the kinetic characteristic of Duffing vibrator in detail. Studied on the chaos discrimination and the chaos criteria. With the deep research on Duffing chaotic system, we present a new method of WSD based on Duffing chaotic system and the correlation method, completed the detection of the signal amplitude. Improved the model of Duffing system, decreased the SNR threshold of Duffing criteria WSD system. Present a method to detect the frequency of the signal to be measured based on the Optimal theory. The results of the experiments showed that the method we presented in this article have much better efficiency than the traditional way, it have certain application value.