基于轨道参数和SAR回波数据的多普勒调频率快速估计

多普勒调频率是SAR方位向压缩的关键参数之一.调频率的失配会带来严重的方位向散焦,从而影响成像质量.基于减灾、防灾目的,需要对SAR数据快速成像,从而相应要求对多普勒调频率进行快速估计处理.根据多普勒调频率快速估计需求,提出了一种基于轨道参数法和Map Drift算法估计多普勒调频率的综合反演算法,利用多普勒调频率与距离的关系,简化整个估计流程,从而提高估计速度.同时给出了一种块数据筛选的方法,用于选择综合反演法中所采用的块数据.实验结果表明,综合反演法能够在满足成像质量要求的基础上,快速估计出多普勒调频率.

Fast Approach of Doppler Rate Estimation Based on Geometry and SAR Echo Data

Doppler frequency rate is one of the key parameters in the azimuth processing of SAR data. Once mismatched, it will cause serious defocusing in azimuth dimension and then result in the degradations of image quality. On the other hand, fast estimation for Doppler frequency rate is necessary for the sake of disaster mitigation. To meet the need of fast estimation of Doppler frequency rate, an approach based on geometry and SAR echo data is put forward in this article, which can simplify the estimation processing according to the relationship between the Doppler frequency rate and range. Besides, the selection strategy for block data used to estimate the Doppler frequency rate is discussed. In the end, corresponding results have been given.