Sentinel-1A卫星TOPS模式数据的SBAS时序分析方法——以黄河三角洲地区为例

SBAS time series analysis technique based on Sentinel-1A TOPS SAR images:A case study of Yellow River Delta

Sentinel-1A是目前在轨运行的新一代SAR卫星,其TOPS成像模式具有宽幅成像的特点,能够实现大范围地表形变监测,目前国内外鲜有基于渐进扫描(terrain observation by progressive scans,TOPS)模式影像的小基线集(short baseline subset,SBAS)处理研究成果发表。以黄河三角洲地区作为研究区,选取了2015年5月—2016年4月27景Sentinel-1A TOPS模式影像,组成了94对干涉影像对,使用ECMWF气象数据估算大气延迟,实现大范围大气相位校正;然后采用SBAS时序分析方法提取了研究区地表累积形变量及形变速率图。研究结果表明,该地区近年来仍存在持续沉降,在广饶镇齐成工业园、广饶盐场及南宅科村周边等地区存在明显的沉降漏斗,沉降监测结果与该研究区已有文献所述沉降规律吻合,证明了TOPS模式SBAS时序分析方法应用于形变监测的可行性和有效性。

Sentinel-1 A is a new generation SAR satellite on orbit. Its TOPS imaging mode is wide imaging mode,which can realize large-scale surface deformation monitoring. There are very rare researches on SBAS processing based on TOPS model images published in China and abroad at present. With the Yellow River Delta as the study area,27 Sentinel-1 A TOPS mode images from May 2015 to April 2016 were selected to generate 94 pairs of interferograms. Then,ECMWF meteorological data were used to estimate the atmospheric delay,which could achieve a wide range of atmospheric phase correction. Finally,the deformation and deformation velocity of the study area were extracted by SBAS timing analysis method. The results show that there is still a continuous settlement in recent years,and there is a significant sedimentation funnel in the vicinity of Qicheng industrial park,Guangrao saltworks and Nanzhaike Village in Guangrao Town. The results of settlement monitoring are consistent with the settlement rules described in the study area,and this proves the feasibility and effectiveness of TOPS model SBAS timing analysis method applied to deformation monitoring.