合成孔径雷达子孔径相位定标方法分析

斜距定标技术是获取高精度SAR(Synthetic Aperture Radar)图像的重要环节之一。传统斜距定标方法通过POS(Position and Orientation System)数据和地面控制点坐标对斜距进行测量，对POS系统的精度有很高的依赖性，且需要获取地面控制点的精确位置信息。为降低斜距定标对POS精度与地面控制点位置精度的要求，该文提出了一种基于子孔径相位的定标方法，通过构建基于SAR子孔径相位的测角模型，利用Cramer-Rao界定量分析其测角精度，并给出了子孔径相位的测距定标模型与精度分析。文章最后分析了子孔径相位定标方法的优势。 

Synthetic Aperture Radar Location Based on Subaperture Phase

The range calibration is one of the most important links in obtaining high precision SAR images. The traditional SAR range calibration method measures the range by the POS data and the coordinates of the ground control point. It has a large dependence on the measurement accuracy of the POS system and needs to obtain the accurate position information of the ground control point. In order to reduce the requirement of slant distance calibration for POS accuracy and position control accuracy of ground control points, a calibration method based on subaperture phase is proposed. The new range calibration based on the phase of subaperture is proposed to get better calibration effect and decrease the strong dependence on POS system. In this paper, we give a model of slant calibration method based on the SAR subaperture phases. The analysis of its Cramer-Rao to test its validity and accuracy is given at the end of the article.