地面起伏对成像及雷达景象匹配的影响

Impact of Terrain Undulations on Imaging and Radar Scene Matching

景象匹配是飞行器导航与定位的一种重要手段 ,其中的雷达图像匹配由于具有全天候的特征而受到人们的重视。在分析了实时雷达图像成像方式的基础上 ,具体分析了地面高程起伏对雷达图像构像的影响 ,并进一步推导出在实时雷达图像上 ,图像像点位移与地面高程起伏的具体关系 ;以及为了保证一定的匹配定位精度 ,对于实飞地区地面起伏的定量要求。同时还对导航定位匹配所用的参考基准图受地面高程起伏的影响情况进行了定量的分析 ,并对理论情况和实际图像进行了计算分析与比较 ,最后得出在给定匹配精度的情况下 ,生成参考图时对成像区域内点之间的高差限制要求。

Scene matching is an important means on navigation and location of aeroplane, and radar image matching is thought a lot by reason of all weather. This article analyzed the real radar's imaging styles. Based on the analysis, the paper discussed the effect of height variation on real radar imaging concretely, and deduced the quantitative relationship between the displacement of image points and height variation in radar imaging. In order to assure the scene matching precision, the requirement of the terrain undulations is explained. In the same way, the effect of height variations on the reference images that used in navigation and location is analyzed quantificationally on the paper. The theoretic condition and the actual image are analyzed and compared. Finally the paper explained the limit of height difference on the region of reference image.