| 引用本文: | 胡国伟，汪 玲，朱岱寅. 一种联合TDCM和PFA的空间目标大转角ISAR成像方法[J]. 雷达科学与技术, 2024, 22(2): 161-169.[点击复制] |
| HU Guowei, WANG Ling, ZHU Daiyin. A TDCM⁃PFA Based Large⁃Rotation⁃Angle ISAR Imaging Method for Space Targets[J]. Radar Science and Technology, 2024, 22(2): 161-169.[点击复制] |
|
| 摘要: |
| 空间目标态势感知是当前航天技术领域的研究热点，逆合成孔径雷达（Inverse Synthetic Aperture Radar, ISAR）是空间目标感知的一种有效手段。为了得到利于目标鉴别的高分辨二维ISAR图像，需要通过增大积累转角来提高方位向分辨率。但是，随着转角的增大，平动与转动之间的耦合增大，使得传统的先平动补偿、后利用转动成像的两步式成像方法不再适用。本文提出了一种结合时域信号共轭相乘（Time Domain Conjugate Multiplication, TDCM）处理与极坐标格式算法（Polar Format Algorithm, PFA）的成像算法，首先利用雷达回波的二维相干性，通过TDCM处理进行平动粗补偿，然后借助PFA的插值操作校正大转角引起的散射点越分辨单元走动（Motion Through Resolution Cell, MTRC）并估计目标相对转动参数。通过迭代处理，持续对平动和转动参数进行优化，提升运动补偿效果。仿真验证了所提成像算法的有效性，与传统算法相比，成像聚焦性更好。 |
| 关键词: 逆合成孔径雷达 空间目标 大转角 运动补偿 |
| DOI：DOI:10.3969/j.issn.1672-2337.2024.02.006 |
| 分类号:TN959.74 |
| 基金项目:上海航天科技创新基金（No.SAST2021‐026） |
|
| A TDCM⁃PFA Based Large⁃Rotation⁃Angle ISAR Imaging Method for Space Targets |
|
HU Guowei, WANG Ling, ZHU Daiyin
|
|
Key Laboratory of Radar Imaging and Microwave Photonics, Ministry of Education, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China
|
| Abstract: |
| Space target situation awareness is a research hotspot in the field of aerospace technology. Inverse synthetic aperture radar （ISAR） is an effective means of space target awareness. In order to obtain a high resolution 2?D ISAR image which is conducive to target discrimination, it is necessary to improve the azimuth resolution by increasing the accumulated rotation angle. However, with the increase of the rotation angle, the coupling between translation and rotation increases, which makes the traditional two?step imaging method of first translation compensation and then rotation imaging no longer applicable. In this paper, an imaging algorithm combining time domain conjugate multiplication （TDCM） processing with polar format algorithm （PFA） is proposed. Firstly, utilizing the two?dimensional coherence of radar echoes, translational coarse compensation is performed through TDCM processing. Then, the motion through resolution cell （MTRC） caused by the large rotation angle is corrected by the interpolation operation of PFA and the relative rotation parameters of the target are estimated. Through iterative processing, the translational and rotational parameters are continuously optimized to improve the motion compensation effect. Simulation results verify the effectiveness of the proposed imaging algorithm. Compared with the traditional algorithm, the proposed algorithm has better imaging focus. |
| Key words: inverse synthetic aperture radar space target large rotation angle motion compensation |
