基于正弦调频傅里叶变换的自旋微动群目标分辨

近年来针对孤立目标的微动特征提取技术已较为成熟,但针对群目标的分辨与微动特征提取技术尚有待深入研究。本文以空间自旋微动群目标为例,提出了一种基于正弦调频傅里叶变换的自旋微动群目标分辨方法。首先建立了自旋微动群目标的回波模型,在此基础上采用正弦调频傅里叶变换来提取回波中的微多普勒特征分量。针对正弦调频傅里叶变换在分析多分量正弦调频信号时所特有的交叉项问题,提出了一种有效的交叉项抑制方法。最后,结合交叉项抑制方法,利用正弦调频傅里叶变换处理自旋群目标微动信号,实现了对自旋微动群目标的分辨,并准确地提取出各子目标自旋频率特征。

Resolution of Group Targets with Spinning Micro-Motion Based on Sinusoidal Frequency Modulation Fourier Transform

The target resolution technique based on the extraction of isolated target micro-motion feature has been relatively mature in recent years, but the extraction of group targets micro-motion feature remain to be further studied. A resolution scheme of group targets with spinning micro-motion based on sinusoidal frequency modulation Fourier transform (SFMFT) is proposed in this paper. First, echo model of group targets with spinning micro-motion is established, based on which, SFMFT is applied to extract micro-Doppler component. Then, a suppression method of cross-term in SFMFT when applied on multi-component sinusoidal frequency modulation signal is put forward. Finally, with the proposed cross-term suppression method utilized, after conducting SFMFT on the micro-motion signal of spinning-group targets, group targets with spinning micro-motion are effectively resolved, and the spinning frequency of each sub-target is accurately extracted.