基于混沌和随机共振的微弱信号检测  

Weak signal detection based on chaos and stochastic resonance

作　　者：高仕龙[1,2] 钟苏川[2] 韦鹍[2] 马洪[2] 

机构地区：[1]乐山师范学院数学与信息科学学院,乐山614000 [2]四川大学数学学院,成都610064

出　　处：《物理学报》2012年第18期45-51,47-48+46+49-51,共7页Acta Physica Sinica

基　　金：国家自然科学基金支持项目(批准号:11171238);中国博士后科学基金(批准号:201104693)资助的课题~~

摘　　要：推导了分数阶线性振子系统响应的一阶稳态矩的频率不变性和相移特性,并通过理论分析得出,在随机共振机制下,分数阶线性振子对系统响应一阶稳态矩的幅值具有放大作用.构造Duffing混沌振子检测器,利用混沌系统对参数摄动的敏感性以及对噪声的免疫能力实现弱信号检测.数值模拟证实,该方法可以有效地从噪声背景中将微弱正弦信号检测出来,并且相对传统的混沌检测方法能显著降低信噪比检测门限.The frequency invariance and phase shift of the first-order steady state moment of system response are deduced for fractional order linear oscillator. Moreover, through the theoretical analysis, the amplification effect of fractional order linear system on the amplitude of first-order steady state moment is verified in stochastic resonance mechanism. Duffing detector is used to realize weak signal detection based on parameter perturbation sensitivity and noise immunity of chaos. Numerical simulations show that this scheme can effectively extract the weak sinusoidal signal from the strong colored noise background and significantly reduce the signal-to-noise ratio threshold in comparison with traditional chaotic detection method.

关 键 词：弱信号检测 随机共振 混沌 分数阶 

分 类 号：TN911.23[电子电信—通信与信息系统]