一种复合微动空间目标窄带成像方法

提出一种复合微动空间目标窄带成像方法。由于窄带雷达在目标检测和跟踪等方面的优势,窄带雷达被广泛用于空间目标探测中。对空间微动目标,微动产生时变多普勒调制,蕴含了目标的重要结构信息,通过对时频图像应用逆约旦变换方法可获取目标各散射点的位置,实现窄带成像。窄带成像降低了对雷达带宽的要求,在空间目标探测上具有优势。然而,在实际探测场景中,目标运动表现为微动和平动的复合叠加,使窄带成像方法失效。在建立复合微动空间目标雷达回波模型的基础上,分析目标的时变多普勒调制特性,提出一种复合微动窄带成像方法,该方法首先基于时频相关系数估计微动周期,利用多普勒相消方法去除平动影响,估计目标平动参数,进而实现平动补偿,最后基于逆约旦变换方法实现窄带成像。所提方法不受目标平动影响,能有效实现复合微动空间目标的窄带成像。

Narrow band imaging method for compound micro motion space target

A narrow band imaging method for space target with compound micro motion is proposed. Due to the advantages of narrow band radar in target detection and tracking, narrow band radar is widely used in space target detection. For space target with micro motion, there is time varying Doppler modulation induced by micro motion, which contains the important structural information of the target. By applying the inverse Radon transform (IRT) method on the time frequency image, the position of scattering centers of the target can be obtained and the narrow band imaging can be achieved. Narrow band imaging reduces the requirement of radar bandwidth and has advantages in space target detection. However, in the real detection scene, the target motion is composed of micro motion and translation, which makes the narrow band imaging method invalid. In this paper, based on the radar echo model of space target with compound micro motion, the time varying Doppler modulation characteristics of the target are analyzed, and a narrow band imaging method for compound micro motion is proposed. Firstly, the micro motion period is estimated based on the time frequency correlation coefficient. Then the translational influence is removed by the Doppler cancellation method, the target translational parameters are estimated, and then the translational compensation is achieved. Finally, the narrow band imaging is achieved based on the IRT. The proposed method is not affected by the target translation, and can effectively achieve the narrow band imaging for space target with compound micro motion.