低信噪比下典型雷达信号调制类型识别  

Modulation Types Recognition of Typical Radar Signal under Low Signal-to-Noise Ratio

作　　者：石涵宇 司伟建[1] 夏新凡 SHI Hanyu;SI Weijian;XIA Xinfan(College of Information and Communication Engineering,Harbin Engineering University,Harbin 150001,Heilongjiang,China;Shanghai Radio Equipment Research Institute,Shanghai 201109,China)

机构地区：[1]哈尔滨工程大学信息与通信工程学院,黑龙江哈尔滨150001 [2]上海无线电设备研究所,上海201109

出　　处：《制导与引信》2023年第4期9-16,共8页Guidance & Fuze

基　　金：航空科学基金(2019010P6001)。

摘　　要：针对低信噪比雷达信号调制类型识别概率低的问题,提出了一种基于分数阶傅里叶变换(fractional Fourier transform,FRFT)频谱四阶原点矩的低信噪比雷达信号调制类型识别方法。该方法首先对输入的雷达信号进行分数阶傅里叶变换,求得分数阶傅里叶频谱四阶原点矩;然后根据分数阶傅里叶频谱四阶原点矩归一化幅度包络,判断其包络中峰值点对应的变换阶数,对雷达信号进行粗识别;最后计算幅度包络的峰态值,通过设置的峰态阈值,比较峰态值大小,判断信号调制类型,实现类内信号调制类型的细识别。仿真实验验证了所提识别方法的有效性。In order to solve the problem of low recognition probability for modulation type of low signal-to-noise ratio radar signal,a modulation type recognition method for low signal-to-noise ratio radar signal based on fourth-order origin moment of fractional Fourier transform(FRFT)spectrum was proposed.Firstly,the input radar signal was fractional Fourier transformed to get the fourth-order origin moment of the fractional Fourier transform spectrum.Then,according to the fourth-order normalized amplitude envelope of fractional Fourier transform spectrum,the radar signal was roughly recognized by judging the transformation order corresponding to the peak point.Next,the kurtosis value of the amplitude envelope was calculated.By setting the kurtosis threshold value,the kurtosis value was compared,the signal modulation type was determined,and the fine recognition of the signal modulation type within the class was achieved.The effectiveness of the proposed method is verified by computer simulation.

关 键 词：调制类型识别 分数阶傅里叶变换 四阶原点矩 变换阶数 峰态值 

分 类 号：TN957.51[电子电信—信号与信息处理]