【作者】 赵莹；

【导师】 隋立春；

【作者基本信息】 长安大学 ， 摄影测量与遥感， 2009， 硕士

【摘要】 星载合成孔径雷达定位指的是:确定星载合成孔径雷达图像中指定目标在指定坐标系下的坐标。众所周知,无论是军用还是民用,为了在遥感应用的各个领域有效地利用星载合成孔径雷达图像,需要对图像像元进行精确的地理定位;在图像的后处理过程中,为了保证图像的几何校正的精度,以及从遥感影像中提取有效的制图信息,均需要对其进行精确的地理定位。本文首先介绍了合成孔径雷达的基本原理,详细推导了距离-多普勒模型的数学表达式,在分析了距离-多普勒模型在图像定位中作用的基础上,系统地给出了基于星载合成孔径雷达头文件中辅助数据直接定位的原理与方法,并通过实际ERS-1图像产品进行定位的试验,具体研究实现该定位方法的细节,详细阐述了该算法中所有参数的获取方法,给出了具体的计算过程,试验结果表明该算法本身有着较高的精度。最后,分析得出本文定位模型的定位精度主要取决于地球模型的有效性、斜距和多普勒参数测量的准确性以及卫星星历数据的精确度等。指出如果能改进雷达的几何关系,增加地球模型描述的有效性,并且改进星上处理器对星历数的调整精度,则将会进一步提高绝对定位的精度。更多还原

【Abstract】 Spaceborne synthetic aperture radar satellite positioning is using to determine the coordinates of designated targets in spaceborne synthetic aperture radar images under the designated coordinates. It is well known that accurate geographic positioning to the pixels of images is required to apply spaceborne synthetic aperture radar images in various fields of remote sensing effectively. In the post-processing of images, accurate geographic positioning is also required to ensure the geometric accuracy of images, as well as to extract effective mapping information from remote sensing images.In this paper, the basic principles of synthetic aperture radar is introduced first, the mathematical expression of Range-Doppler model is derived in detail. Based on analyzing the effect of Range-Doppler model in positioning of images, the principal and methods of direct positioning using the assistance data in head file of spaceborne synthetic aperture radar. By the positioning experiment of actual ERS-1 image, the detail of the positioning method is studied concretely, and the acquisition methods of all parameters in the algorithm are expatiated in detail. Also the concrete calculation processing is given out. The results of experiment show that the algorithm has a high accuracy. Finally, after analysis, the positioning accuracy of the positioning model in this paper is mainly influenced by effectiveness of the earth model, slant range, and the accuracy of both Doppler parameters measurement and satellite ephemeris data. It is pointed out that the accuracy of absolute positioning could be further improved if the geometric relationship of radar, the effectiveness of earth model and the adjustment accuracy of satellite ephemeris data could be improved.更多还原