主星带伴随微小卫星编队SAR系统的空间分辨率分析

根据主星带伴随微小卫星编队SAR系统的结构特点,建立了双站SAR系统的几何模型,然后推导分析了距离分辨率和方位向分辨率的解析表达式,最后仿真分析了以ENVISAT作为主星、"干涉车轮"的距离分辨率和方位向分辨率随主星到编队小卫星的距离、相对轨道高度的变化情况,并且与主星SAR的分辨率进行了比较。结果表明:(1)空间分辨率大小随波束入射角的变化基本上与主星一致;(2)空间分辨率随主星与伴随小卫星的距离增大而增大;(3)空间分辨率之差随微小卫星相对椭圆轨道短轴的增加而增加。

Analysis of Spatial Resolution for Spaceborne Parasitic SAR System

Based on the framework of spaceborne parasitic SAR system and considering spaceborne bi-static SAR configuration formed by the existing satellite and each micro-satellite, a geometrical model is established, and formulations of spatial resolution in range and in azimuth are deduced. Finally varieties of the spatial resolution in range and in azimuth along with the angle of incidence, height of the relative orbit and the range between the existing satellite and micro-satellite are simulated and analyzed. The results indicate: (1) the spatial resolution in range and in azimuth are very similar to the existing satellite's; (2) the range between the existing satellite and micro-satellite is longer, the spatial resolution is bigger; (3) the height of the relative orbit is greater, the differences of spatial resolutions of each micro-satellite are bigger.