应用分数傅立叶变换方法的水下目标特征提取

针对基于传统时频分析方法的水下目标特征提取方法的缺陷,引入了一种新的时频分析方法——分数阶傅立叶变换（FRFT）方法用于处理水下目标特征提取问题。仿真信号和实际试验数据的处理结果表明,当主动声纳的发射信号为线性调频信号时,分数阶傅立叶变换方法可以使目标的回波能量在分数阶域的对应区域聚集,使目标和混响的分数阶傅立叶变换在分数阶域上不仅呈现明显不同的特征,而且较其他时频分析方法具有抗混响的优点。

Characteristic extraction of underwater targets by using fractional Fourier transform

A new method of time-frequency analysis,Fractional Fourier Transform (FRFT),is proposed for the target characteristics extraction.Shown by the results of simulation and experimental data with the chirp signal being transmitted,FRFT can concentrate the energy of target echo into the corresponding fractional domain which results in the properties of the fractional Fourier spectrum of target echo quite different from that of the reverberation,and contribute higher recognition accuracy than other time-frequency...