基于S-Method分布的微多普勒特征分析

Analysis of micro-Doppler features based on S-Method

微多普勒特征是雷达目标所具有的独特特征之一,对目标的分类、识别具有特殊的意义。研究高精度时频分析方法在分析目标微动特性中的作用,可以为后续目标识别提供很好的支撑。S-Method分布作为一种新型的时频分析方法,它基于短时傅里叶变换来实现,减少了分析过程中的运算量,同时能较好地解决交叉项问题。首先对弹道导弹弹头的微动模型进行建模,推导得到微动模型的理论微多普勒频率,然后采用S-Method分布对回波信号进行时频分析仿真实验,获得弹头目标章动的高精度的时间-微多普勒频率图。通过比较其在分析过程中的时频分辨率、交叉项,具体阐述S-Method分布在时频分析中的优势。因此可以将S-Method分布应用于雷达目标微多普勒分析中,分析实时变化的微多普勒频率特征。

Micro-Doppler features is one of the unique features of radar target and it has the special significance for target classification and recognition.Researching on the method of time-frequency analysis in analyzing micromotionfeatures can provide good support for subsequent recognition.S-Method distribution as a new method of timefrequency analysis,based on short-time Fourier transform,reducing the amount of analysis in the process of operation,and is able to solve the cross term problem.Firstly,to model the micro-motion model of ballistic missile warheads,derived micro-Doppler frequency of micro-motion model,then using S-Method distribution on time-frequency analysis of echo signal simulation,obtained the warhead target high-precision time-micro-Doppler frequency graphs.By comparing the time-frequency resolution and cross term in its analysis,S-Method distribution advantage in the time-frequency analysis was explained in detail.So S-Method distribution can be applied to analysemicro-Doppler frequency characteristics of real time changes.