时序合成孔径雷达干涉测量的多级化解算

A Multi-level Approach for Multi-temporal Interferometric Synthetic Aperture Radar

摘要:

利用2007~2010年C波段ENVISAT， 2010~2015年X波段TerraSAR-X以及2016~2018年C波段Sentinel-1A数据，基于时序合成孔径雷达干涉测量（MT-InSAR）技术对上海磁悬浮及其周边区域进行沉降监测，绘制了该区域的沉降速率图.综合考虑点密度以及空间分布，提出一种优化的多级化高相干点网络的数据处理方法，在保证测量精度的前提下，有效地提高了可用相干点的数目.对比不同波段的数据，分析了距离以及方位向图像分辨率对相干点数目的影响.试验表明，磁悬浮轨道上的相干点数目与距离向分辨率密切相关.利用实测水准数据，验证了MT-InSAR测量结果的可靠性.结果表明，磁悬浮周边存在多个沉降明显的区域，而磁悬浮轨道一直保持稳定.

Abstract:

Multi-temporal interferometric synthetic aperture radar (MT-InSAR) technology was applied to process C-band ENVISAT data from 2007 to 2010, X-band TerraSAR-X from 2010 to 2015 and C-band Sentinel-1A from 2016 to 2018 to monitor ground subsidence along the Shanghai maglev zone and velocity maps were plotted. An optimal multi-level network with high coherent points considering both point density and distribution was used to increase the number of coherent points with high precision efficiently. Comparing the data with different wavebands, the relationship between the image resolution along azimuth and range direction and the number of coherent points was analyzed. The experiments have shown that the coherent points along the maglev track are closely related to the range resolution. In addition, the velocity map obtained by MT-InSAR was evaluated using the levelling data. The result shows the maglev track is stable although there are several subsiding troughs near the maglev track.