作者

Yufeng Wu, Guangcai Sun, Xiang-Gen Xia, Mengdao Xing, Zheng Bao

发表日期

2012/11/10

期刊

IEEE Geoscience and remote sensing letters

卷号

10

期号

4

页码范围

741-745

出版商

IEEE

简介

Doppler rate is an important parameter in synthetic aperture radar (SAR) signal processing since it affects the SAR image focusing. There are many approaches to estimate the Doppler rate from SAR data; however, some approaches are not appropriate for spotlight SAR, which is focused with the two-step algorithm, since, after azimuth preprocessing, the signal is aliased in the azimuth time domain. Although the shift-and-correlation (SAC) algorithm may be suitable for such signals, it is proposed for the stripmap imaging mode; and when it is used to estimate the Doppler rate for spotlight SAR, some problems, such as the high computational load from zero padding and the constraint of the focus depth, may occur. In this letter, an improved Doppler rate estimation approach, which is called the Keystone-SAC algorithm, is proposed. An iterative scheme is presented to estimate the ambiguity number, and a special case …

学术搜索中的文章

Y Wu, G Sun, XG Xia, M Xing, Z Bao - IEEE Geoscience and remote sensing letters, 2012