融合升降轨PS-InSAR东营市地面沉降监测

Land subsidence monitoring in Dongying with integrated lift rail PS-InSAR

针对PS-InSAR技术存在单一轨道覆盖率低、升降轨道基准难以统一的问题,提出一种融合升降轨数据共同获取地面形变场的方法。利用覆盖东营市的84景Sentinel-1A雷达卫星数据,采用PS-InSAR技术分别获得升轨和降轨下的垂直向形变量,进行升降轨解算结果内部互检。通过抗差最小二乘曲面拟合法统一参考基准,实现升降轨观测序列的数据融合,最终得到地面形变场。实验结果表明:升降轨下同名相干点内部互检相关系数优于0.8;升降轨数据融合中抗差最小二乘拟合法较传统方法点位精度提升3.3 mm;东营市在2018年1月至2019年7月期间地面沉降分布呈现东部沿海大于西部城区的特点,且最大沉降量为-458 mm。

Aiming at the problems of low coverage of a single orbit in the PS-InSAR technology and the difficulty of unifying the orbiting reference,a method of fusing the data of the orbiting together to obtain the ground deformation field is proposed.Using the data of 84 Sentinel-1A radar satellites covering Dongying City,PS-InSAR technology was used to obtain the vertical deflection variables under the ascending and descending orbits.The fitting method unifies the reference datum,realizes the data fusion of the ascending and descending observation sequence,and finally obtains the ground deformation field.The experimental results show that the correlation coefficient of the internal mutual comparison of coherent points of the same name is better than 0.8,and the robust least squares fitting method in the fusion of the ascending and descending data improves the point accuracy by 3.3 mm compared to the traditional method.During the period from January 2018 to July 2019,the distribution characteristics of land subsidence in Dongying City showed the the eastern coastal area was of larger subsidence than that of the western urban area,and the maximum settlement amount was-458 mm.