%0 Journal Article
%T IMPROVEMENT OF AUTOFOCUSING TECHNIQUE FOR RANK ONE PHASE ERROR ESTIMATION<br>秩-相位误差估计自聚焦方法的改进
%A Li Liwei
%A Asif Raza
%A Mao Shiyi
%A <br>李立伟
%A Asif Raza
%A 毛士艺
%J 电子与信息学报
%D 1999
%I 
%X This paper presents an improved rank one phase error estimation(ROPE) autofo-cusing technique. Compared with ROPE, the improved algorithm has two distinct advantages: first, its model is more actual, so its property of robustness is better; second, at the begining of its iteration process, the initialized valves are set up approximately. Through approximate analysis, this paper proves that the improved algorithm's estimation of phase error is maximum-likelihood (ML), and, under some special situaitons, its estimation is the same as that of phase gradient autofocus (PGA), which is linear unbiased minimum variance (LUMV) estimation. PGA is a subset of this improved autofocus algorithm. Finally, some simulation results are given.
%K SAR
%K Autofocus algorithm
%K Phase gradient autofocus (PGA)
%K Rank one phase error estimation<br>SAR
%K 自聚焦算法
%K 相位梯度自聚焦(PGA)
%K 秩-相位误差估计
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=5B3AB970F71A803DEACDC0559115BFCF0A068CD97DD29835&cid=1319827C0C74AAE8D654BEA21B7F54D3&jid=EFC0377B03BD8D0EF4BBB548AC5F739A&aid=F1EECC2A4DCD69BA0A2EAD34F964BC25&yid=B914830F5B1D1078&vid=659D3B06EBF534A7&iid=B31275AF3241DB2D&sid=E3691231514F8E11&eid=0358FC3DBCE8E14D&journal_id=1009-5896&journal_name=电子与信息学报&referenced_num=0&reference_num=6