基于相位空间相关性分析的PSInSAR技术在地面沉降监测中的研究与实践  

A Study and Practice of Land Subsidence Monitoring with PSInSAR Based on Phase Spatial Correlation Analysis

作　　者：刘欢欢[1] 范景辉[2] 陈建平[3] 郭小方[2] 

机构地区：[1]中国地质博物馆,北京100034 [2]中国国土资源航空物探遥感中心,北京100083 [3]中国地质大学北京市国土资源信息开发研究实验室,北京100083

出　　处：《地理与地理信息科学》2012年第3期15-19,F0002,共6页Geography and Geo-Information Science

基　　金：国家公益性基金项目"地质灾害雷达干涉测量预警系统的研究与设计"(200811053)

摘　　要：PSInSAR技术克服了图像失相干和大气影响等限制因素,扩展了DInSAR在提取大面积微小形变上的应用,但基于亮度离散度和先验形变模型的PSInSAR有一定的局限性。基于相位空间相关性分析的PSInSAR技术通过分析相位各个组分的空间相关性,完成PS的选择和形变信息提取,可以在没有亮散射体的情况下选取PS点和提取各种地表形变信息,且不受先验的形变时间模型限制,可应用于各种形变研究。该文以天津地区地面沉降监测实践为例,描述了该方法的关键技术和工作流程,利用14幅ENVISAT SAR数据,得到了较好的监测结果。PSInSAR （Permanent Scatter InSAR） is possible to avoid many of the limitations of conventional DInSAR by only an- alyzing certain pixels which behave like point scatters and retain some degree of correlations. But in almost all of these algo- rithms,an initial set of PS pixels is selected by amplitude variation,and this kind of method may fail in non-urban areas because the relationship between amplitude dispersion and phase stability will break down for low SNR scatters. Besides, approximate temporal models are required to refine PS, estimate and remove nuisance terms. In this paper, an algorithm is introduced, by ana- lyzing the spatial correlation of interferogram phase;a network of stable pixels can be gotten in almost all terrain without prior knowledge of temporal variations in the deformation. As the new method is not restricted by deformation model, we can get the deformation information for each data-acquisition time, which improves the time resolution and has a significant guide to the a- nalysis of the deformation laws and causes. The authors will also state the work-flow afterward, that is, noise estimation, phase unwrapping and deformation information extraction. In this paper, by using 14 ENVISAT ASAR SLCs covering from Oct 2003 to Dec 2005 for Tianjin area,SRTM DEM and DEOS precise orbits,this method is applied to monitor the substance in Tianjin test area. After the interferogram series formation, PS identify and selection, and deformation estimation, the PS temporally de- formation sequence and yearly, spatially discrete deformation velocity in LOS are got. Kriging interpolation is at last applied to get a continuous deformation sense. And the result proves that the method is effective.

关 键 词：相位空间相关性 PSINSAR 地面沉降 

分 类 号：P642.26[天文地球—工程地质学]