基于混沌相平面变化的微弱信号检测  

A Weak Signal Detection Approach Based on Change of Chaotic Phase Trace

作　　者：张浩然[1] 侯楚林[2] 

机构地区：[1]海军航空工程学院海军装备部,北京100071 [2]海军工程大学兵器工程系,湖北武汉430033

出　　处：《计算机测量与控制》2010年第12期2718-2720,共3页Computer Measurement &Control

基　　金：国家自然科学基金资助项目(10272113)

摘　　要：针对超低信噪比条件下信号难于检测这一问题,提出了一种基于Duffing振子的微弱信号检测新方法,采用梅尔尼科夫函数给出了系统出现混沌状态的阈值,分析了Duffing振子动力学系统随参数变化的特性,研究了系统在临界参数附近变化时会出现混沌到大周期相变的特征,并根据此特点设计了一种微弱信号检测模型;理论分析和仿真实验都表明,提出的检测方法对任何零均值噪声具有免疫力,对正弦信号参量变化极为敏感,且可以准确检测出信噪比低达-49.5dB的微弱正弦信号。In view of existing questions in detecting signals for the case of ultra-low signal-noise –ratio（SNR）,a new weak signals detection method based on the Duffing oscillator is proposed.The threshold of the detection system is given by using Melnikov function.The characteristic of Duffing oscillators with the changing of dynamics of the system is also analyzed.The method of detection of weak signals in strong noise based on Duffing oscillators is presented by exploiting characteristic of phase changing from chaos state to great periodic state of system nearby critical coefficient.The theoretic analysis and the numerical result confirm the conclusion that the method presented is immune to zero mean square non-Gaussian color noise and very sensitive to weak variation for sine wave parameters.

关 键 词：微弱信号 杜芬振子 梅尔尼科夫函数 阈值 相变 

分 类 号：O322[理学—一般力学与力学基础] TN911.23[理学—力学]