机载视频合成孔径雷达成像技术研究

Study of Airborne Video Synthetic Aperture Radar

机载视频合成孔径雷达(ViSAR)工作在太赫兹波段,具有5 Hz以上的无孔径交叠成像帧率。其采用一发四收系统架构,具备合成孔径雷达(SAR)成像、地面动目标检测(GMTI)和干涉合成孔径雷达(InSAR)测高等功能,兼具光学传感器成像速度快以及微波雷达环境与气候适应性好等优势。论文介绍了机载视频合成孔径雷达研究进展,实验表明,其成像分辨率优于0.2 m,合成孔径时间可缩短至0.2 s。利用阴影信息可以对运动目标(如卡车等)进行检测,结合传统的GMTI与InSAR技术,实现对复杂运动目标的成像、跟踪和定位。

Airborne video synthetic aperture radar(ViSAR) works at terahertz frequency,whose imaging frame rate with no aperture overlap is more than 5 Hz, so the airborne ViSAR has both the advantages of high imaging speed of optical sensor and superior environmental adaptability of microwave radar. It adopted architectures with one transmitter and four receivers, which endowed the radar with multiple functions, such as synthetic aperture radar(SAR)imaging, ground motive target indication(GMTI) and interferometric synthetic aperture radar(InSAR)altimetry. This paper introduces the study progress of the airborne ViSAR, the experiments show that the resolution of radar is better than 0.2 m, and within the synthetic aperture time of 0.2 s, normal moving targets(such as tank and armored vehicle) only move a short distance, and would leave clear shadows on the ground, which are good for targets detection. Combining traditional GMTI and InSAR technologies, the airborne ViSAR could realize arbitrary moving targets imaging and tracking, and provide precise guidance for weapon systems.