C-band和L-band雷达干涉数据西部冰川区域相干性对比分析

A COMPARATIVE STUDY OF COHERENCE PATTERNS OF C-BAND AND L-BAND INTERFEROMETRIC SAR IN WESTERN GLACIER AREAS

干涉雷达相干性问题是制约利用干涉方法提取中国内陆冰川相关参数的重要原因。本文在理论分析干涉空间失相干因素的基础上,从垂直基线、地面坡度和波长3个方面对比了雷达干涉数据在内陆冰川表面的干涉特性。以中国西部典型的内陆冰川(冬克玛底冰川)为研究区域,采用C-band的ENVISAT/ASAR和L-band的ALOS/PALSAR数据,对比分析二者在冰川区域相干性的差别,并给出了量化结果。研究表明,相比于C-band雷达干涉数据,L-band雷达干涉数据在内陆冰川区域具有更强的抗失相干的能力,更适合于内陆冰川相关参数的提取。

Decorrelation is one of the key restrictive factors when the InSAR technique is used to derive the parameters of inland glaciers in China.This paper has compared the coherence patterns between different perpendicular baselines,terrain slopes and wavelengths from both the theoretical and the experimental results based on analyzing the factors leading to the interferometric spatial decorrelation.Taking the Dongkemadi Glacier of western China as the study area,the authors analyzed the different coherence patterns of the Dongkemadi Glacier by using C-band ENVISAT/ASAR and L-band ALOS/PALSAR data.The quantitative result is also given.The results indicate that the capability of the coherence by ALOS/PALSAR repeat-pass pairs is higher than that of the coherence by ENVISAT/ASAR pairs.The L-band ALOS/PALSAR data are more fit for extracting the parameters of the inland glacier.