月基SAR对地观测时空特性研究

Research on Spatio-Temporal Characteristics of Moon-Based SAR Earth Observation

月基雷达能对地表目标进行长时间大尺度范围的观测。根据美国喷气推进实验室(Jet Propulsion Laboratory,JPL)星历数据,分析了月基合成孔径雷达微波(Synthetic Aperture Radar,SAR)平台在不同场景时对地球在时间上和空间上观测性能的差异,结合实际地月相对运动的空间关系完成了月基SAR回波的仿真。结果表明:通过月基SAR平台,可以找到位于地表的零多普勒面交线,并以此为基础实现较长时间、较大地面范围的周期性观测,用SAR回波仿真验证了其可行性。通过研究月基SAR的观测,可以为后续研究诸如地表潮汐运动、极区海冰回弹提供基础。

With the rapid development of lunar exploration,the concept of moon-based observation of earth has received more and more attention.The synthetic aperture radar(SAR)deployed on the moon for earth observation can obtain continuous observations of large areas on earth surface,and realize a single wide-area observation mode which makes up for the deficiency of space-borne SAR.Based on the JPL ephemeris data,in this paper the observation difference of moon-based SAR in different scenarios such as time domain and space domain was analyzed,and the simulation of SAR echo was completed using the actual earth-moon spatial relationship.The results show that the moon-based SAR can always find the intersection line of zero Doppler plane on earth surface,and long-term,large-scale periodic observations can be achieved.The SAR echo simulation verifies its feasibility.The study of moon-based SAR observations can provide a basis for follow-up studies such as surface tidal movement and polar sea ice rebound.