一种InSAR大气相位建模与估计方法  

A strategy for modeling and estimating atmospheric phase of SAR interferogram

作　　者：占文俊 李志伟[1,2] 韦建超[1,2] 朱建军[1,2] 汪长城[1,2] 

机构地区：[1]中南大学地球科学与信息物理学院,长沙410083 [2]中南大学有色资源与地质灾害探查湖南省重点实验室,长沙410083

出　　处：《地球物理学报》2015年第7期2320-2329,共10页Chinese Journal of Geophysics

基　　金：国家高技术研究发展计划项目(2012AA121301);国家重点基础研究发展计划(2012CB719903);国家自然科学基金(41222027;41474007;41404013);湖南省杰出青年科学基金(13JJ1006);教育部博士点基金(20130162110015)资助

摘　　要：为了削弱大气延迟对干涉结果的影响以提高InSAR的测量能力,本文在InSAR大气相位特征分析的基础上,研究了一种新的InSAR大气相位建模与估计方法.首先采用稳健估计确定大气垂直分层部分的模型参数,然后利用基于Matern模型的Kriging插值估计大气紊流部分,最后应用估计的大气垂直分层和紊流资料改正InSAR测量结果.利用覆盖河南义马地区的ASAR数据对本文提出的方法进行了验证,结果表明去除大气影响后,InSAR重建的DEM与参考DEM的高程差异的均方误差由19.5m降至5.3m,精度提高了约72%.同时,改正后的干涉图更合理地揭示了义马矿区的沉降漏斗情况,进一步验证了本文方法的有效性.The atmospheric effect is one of the most important limiting factors to Interferometric Synthetic Aperture Radar（InSAR）measurements.It can seriously degrade the quality of InSAR measurements or even render the technology unusable.It is of great importance to develop methods to model and mitigate this effect.A novel method for modeling and estimating the atmospheric phase in SAR interferograms is proposed.The method starts with the spatial and temporal analysis of the characteristics of the atmospheric effects in InSAR.Based on this,it constructs relevant models to describe the stratification and turbulent mixing of atmospheric effects,respectively.Then,it develops the method of robust estimation to determine the model parameters of the stratified atmospheric components,and the method of Matern variogram model-based Kriging interpolation to estimate the parameters of turbulent atmospheric components.Finally,it applies the developed method to estimate and correct the atmospheric effects in InSAR measurements.The proposed method is validated with one ASAR pair over the Yima area in HenanProvince.The results show that after the atmospheric correction,the root mean square error of the differences between the InSAR-reconstructed and the reference DEM reduce from 19.5mto5.3m,representing an improvement by 72%.In addition,after the correction,the sign of the line-of-sigh（LOS）range change in a mining area varies from positive to negative,indicating that subsidence rather than uplift happening in this area.The corrected interferogram much better reveals the development of the＂subsidence bowl＂in the mining area.This paper developed a novel method for modeling and mitigating atmospheric effects in InSAR.The method fully exploits the spatial characteristics of atmospheric effects in InSAR,and considers the stratified and the turbulent mixing atmospheric effects as well.Besides,it adopts the Matern model rather than the traditional variogram model in the turbulent mixing modeling.So it works very well.Future work w

关 键 词：合成孔径雷达干涉 大气相位 建模与估计 稳健估计 Matern模型 

分 类 号：P225[天文地球—大地测量学与测量工程]