Based on the SAR satellite images from 2015 to 2019, this paper proposes a novel wide-area InSAR time series analysis technology for high-precision and continuous monitoring of the surface deformation in the North China Plain. Firstly, standard interferometric processing is carried out on SAR images to obtain the interferogram. Then the parallelized StaMPS method is used to extract all PS pixels in the interferogram and obtain the deformation time series with full resolution. Next the atmospheric noise is estimated and removed using the joint atmospheric correction method, through combination of the atmospheric model correction and common scene stacking. After this processing flow, we successfully obtain a solution of large spatial scale, long-term span, full spatial resolution, and high precision deformation in the North China Plain, and detect the subsidence deformation pattern with a strong signal of up to 100 mm/a in central plain due to groundwater extraction. Compared with existing algorithms, the parallelized StaMPS method saves at least 60% of computing time through real-time distribution among multiple computing nodes. Besides, the joint atmospheric correction method can remove about 74.3% of the atmospheric noise, and its effectiveness is significantly higher than that of using the two correction methods alone. This wide-area InSAR time series analysis technique can effectively realize high-precision continuous monitoring of large-scale surface deformation. 

wide-area InSAR time series analysis technique, parallelized StaMPS method, joint atmospheric correction method, surface deformation, North China Plain

基于2015—2019共4年的合成孔径雷达(SAR)卫星影像, 提出一种广域合成孔径雷达干涉测量(InSAR)时序分析技术, 对华北平原的地表形变进行高精度连续监测。首先对SAR影像进行干涉处理, 得到干涉图。在此基础上, 使用经过并行化改进的永久散射体技术斯坦福改进(StaMPS)方法, 提取干涉图中所有永久散射体(PS)像元, 获取研究区域全分辨率的时序形变信息。之后, 使用大气模型校正法与共景叠加法相结合的联合大气校正方法, 估计并去除形变信息中的大气噪声。经过上述处理流程后, 成功地获取华北平原地表大空间尺度、长时间跨度、全空间分辨率和高精度的形变信息, 进而监测到平原内部由长期地下水开采导致的高达100 mm/a 的大范围强烈沉降信号。相较于既有算法, 并行化StaMPS方法通过在多个计算节点之间的实时分配, 节约至少60%的计算时间, 联合大气校正方法则可以去除约74.3%的大气噪声项, 有效性显著高于两种校正方法的单独使用效果。广域 InSAR时序分析技术可以有效地实现对大范围地表形变的高精度连续监测。