基于Wigner-Ville平面相关函数的微动特征提取算法

Feature Extraction for Micro-motion Based on Wigner-Ville Correlation Function

以进动、章动等周期性的旋转和振动为主的微动是弹道导弹弹头的重要识别特征,而空间目标上游动部件(天线等)的旋转运动则会导致雷达成像的散焦。因此,旋转周期等微动特征的提取和估计是对上述目标进行成像和识别的基础。文中在旋转散射点的回波模型基础上,针对目标回波是线性调频-正弦调频混合调制信号的特点,提出了基于WignerVille平面相关函数的微动特征提取算法,证明了Wigner-Ville平面的交叉项对参数提取没有影响。通过仿真对比分析验证了算法的有效性。

The technique of feature extraction with the core of estimation of spin period is a base for imaging and identification of warhead and other spinning targets in space. The accuracy of spinning speed estimation would affect directly the results of imaging and identification. Starting from the radar scattering mechanism of spinning target, this paper brings forward a model for the funda- mental frequency echo of rotation scattering points. The echoes are multi-component LSFM signals when the motion of the target is coupling of the translational motion and the rotation. The estimation method based on the correlation function of Wigner-Ville distri- bution is proposed, which has the best energy aggregation. By simulation,it is proved that this proposed algorithm has a higher pre- cision and stability, thus possessing a well application prospect.