### 基于短时傅里叶变换的Duffing振子微弱信号检测

1. 1. 空军工程大学 理学院, 西安 710051;
2. 西安通信学院, 西安 710106;
3. 西安邮电大学 电子工程学院, 西安 710061
• 收稿日期:2014-10-17 修回日期:2015-01-07 出版日期:2015-10-15 发布日期:2015-01-13
• 通讯作者: 牛德智, Tel.: 029-84786706 E-mail: niudezhi_001@163.com E-mail:niudezhi_001@163.com
• 作者简介:牛德智 男, 博士, 讲师。主要研究方向: 通信系统与雷达信息处理。 Tel: 029-84786706 E-mail: niudezhi_001@163.com;陈长兴 男, 博士, 教授, 博士生导师。主要研究方向: 信号与信息处理, 现代通信理论, 信息系统建模与仿真。 Tel: 029-84786706 E-mail: xachenchangxing@126.com
• 基金资助:

陕西省自然科学基础研究计划项目 (2014JM8344)

### Weak signal detection with Duffing oscillator based on short time Fourier transform

NIU Dezhi1,2, CHEN Changxing1, CHEN Ting3, REN Xiaoyue1, WANG Zhuo1, CHENGMENG Jiangchuan1, JIANG Jin1

1. 1. Science College, Air Force Engineering University, Xi'an 710051, China;
2. Xi'an Communications Institute, Xi'an 710106, China;
3. School of Electronic Engineering, Xi'an University of Posts & Telecommunications, Xi'an 710061, China
• Received:2014-10-17 Revised:2015-01-07 Online:2015-10-15 Published:2015-01-13
• Supported by:

Project supported by the Natural Science Foundation of Shaanxi Province (2014JM8344)

Abstract:

Time frequency characteristic of three statuses such as chaos, intermittent chaos and great period appearing in signal detection process with Duffing oscillator is studied and a frequency signal detection method based on new detection statistics is proposed. By analyzing on system output sequence in different statuses with short time Fourier transform (STFT), it is found that contour line of amplitude and three-dimensional time frequency distribution could represent differences of three statuses and recognize the three statuses utterly. Considering being easily operated on the detection statistics, amplitude-time characteristic in three-dimensional time frequency distribution is made as a foundation to weigh different statuses. Further, maximum of average value of number in amplitude-time characteristic corresponding to each frequency is set to final detection statistic, whose computation could be realized by fast Fourier transform (FFT) so that there will be high time effectiveness. On the basis of it, frequency control unit is brought in Duffing oscillator and scheme of any frequency signal detection is given. The key point of the scheme is to find the maximum among all detection statistics and makes its matching frequency as one port of unknown signal frequency range. Then the other port is the matching frequency of secondary maximum among other two detection statistics adjacent to the maximum. After experiment, the range of detection statistics of each status is given. Thus, according to the range, any frequency signal detection by Duffing oscillator is realized, which shows feasibility of the method and provides one new thought for studying signal detection problem with Duffing oscillator.