提出了一种无需外部数据的新同震形变偏移量计算流程。以2003年伊朗巴姆里氏6.6级地震为例,利用两景震前无形变数据证明了新方法的精度较传统方法提高了0.224个像素。利用震前震后两景数据计算了方位向同震形变场,与Okada模型模拟得到的方位向同震形变进行了比较。
The traditional methods for estimating pixel offsets of two SAR images use the orbit offsets of several points to fit the orbit offsets of the whole image by using the least squares rule,and then removes them from the total offsets.However,the procedures of data processing are quite complicated.What's more,without GCPS,this method contained many kinds of error sources which lead to low precision.To overcome these limits,this paper presents a new simple data processing chain for calculating co-seismic offsets which need no GPS data.In order to compare the precision of two methods,we take the Ms6.6 Bam earthquake occurred in 2003 as an example.First,we processed two SAR images acquired before earthquake with the traditional and the new pixel offset methods respectively.The results show an improvement of 0.224 pixels in precision for the new method.Second,we applied the new and the traditional method to process two images acquired before and after the earthquake.The results indicate that the new method has a higher efficiency and precision.