基于短时傅里叶变换的Duffing振子微弱信号检测

发布时间：2018-01-12 04:38

本文关键词：基于短时傅里叶变换的Duffing振子微弱信号检测　出处：《航空学报》2015年10期 　论文类型：期刊论文

【摘要】：研究了Duffing振子信号检测过程中混沌、间歇混沌和大周期状态的时频特征,提出了一种基于检测统计量的任意频率信号检测方法。通过对系统不同状态下的输出序列进行短时傅里叶变换(STFT)发现,等幅线和三维时频分布能够体现出不同状态的显著差异,且可以完全区分出每一种状态。从构造统计量的易实现性出发,用三维时频分布中的幅时曲线作为衡量不同状态的依据,并将不同频率对应的幅时曲线的均值最大量作为检测统计量,该统计量的计算可以借助快速傅里叶变换(FFT)操作提高时效性。在此基础上,引入频率控制单元,给出了任意频率信号的检测方法步骤,方法的关键是将检测统计量最大值处所在的频率作为待测信号频率范围的一个端点,另一个端点为毗邻的两个检测统计量值较大者所在频率点。实验给出了不同状态的检测统计量范围,进而以此范围为判据,实现了振子对任意频率信号的检测,说明了方法的可行性,为Duffing振子信号检测问题的研究提供了一种新的思路。
[Abstract]:The time-frequency characteristics of chaos, intermittent chaos and large period state in Duffing oscillator signal detection are studied. A detection method for arbitrary frequency signals based on detection statistics is proposed. The output sequences in different states of the system are detected by STFT (short time Fourier transform). The equal amplitude line and 3D time-frequency distribution can reflect the significant difference of different states and can completely distinguish each state. The amplitude-time curves in 3-D time-frequency distribution are used as the basis for measuring different states, and the maximum mean value of amplitude-time curves corresponding to different frequencies is taken as the detection statistics. The calculation of the statistic can improve the time-efficiency by using the fast Fourier transform (FFT) operation. On this basis, the frequency control unit is introduced, and the steps of detecting the arbitrary frequency signal are given. The key of the method is to use the frequency at the maximum value of the detection statistic as an endpoint of the frequency range of the signal to be tested. The other end point is the frequency point of two adjacent detection statistics. The range of detection statistics of different states is given in the experiment, and the detection of any frequency signal is realized by using this range as the criterion. The feasibility of the method is illustrated, which provides a new idea for the research of Duffing oscillator signal detection.
【作者单位】：空军工程大学理学院;西安通信学院;西安邮电大学电子工程学院;
【基金】：陕西省自然科学基础研究计划项目(2014JM8344)~~
【分类号】：TN911.23
【正文快照】： 网络出版地址:www.cnki.net/kcms/detail/S1000-6893.2015.0012.html引用格式:Niu D Z,Chen C X,Chen T,et al.Weak signal detection with Duffing oscillator based on short time Fourier transform[J].ActaAeronautica et Astronautica Sinica,2015,36(10):3418-3429.牛德

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