“高分三号”卫星图像干涉测量试验

Image Interferometry Experiment of GF-3 Satellite

由于自然或人工建造引起的形变可能引发灾难,对其进行形变量监测非常必要,合成孔径雷达(SAR)技术与传统监测技术相比,可以实现全天候对地观测,并监测地表的形变。"高分三号"(GF-3)卫星作为中国国首颗SAR卫星,是否具有干涉测量的能力以及精度尚待验证,为此文章利用GF-3卫星SAR数据对河南省登封市周边地区进行二轨差分干涉处理,获取了该地区的地表形变图。结果表明地表相对沉降量为±0.03m,验证了GF-3卫星作为SAR卫星具有了干涉测量(InSAR)的能力。针对GF-3卫星数据由于轨道误差引起的平行条纹导致相位解缠效果不好的问题,提出利用SRTM(Shuttle Radar Topograpty Mision)DEM高程作为所选样本点的高程,选取5个地面控制点,消除了由于轨道误差引起的平行条纹,提高了反演的形变量精度;GF-3卫星与技术成熟的"哨兵一号"卫星同一测区数据对比,形变信息大致相同。GF-3卫星作为一颗SAR新星具有干涉测量的能力,同时精度上也满足监测的需求。

It is necessary to monitor deformation caused by natural or man-made structures which may even cause disasters.Compared with traditional monitoring technologies,synthetic aperture radar(SAR)technology is capable of monitoring surface deformation with all-weather observation.Considering the capability of GF-3 satellite,China's first SAR satellite,on interference measurement and its accuracy haven’t yet verified,the SAR data in Dengfeng district,Henan province,is used to construct the surface deformation map by 2 rail differential interference processing.The results of surface relative settlement is about±0.03m,which shows the capability of SAR interferometry(InSAR)on GF-3 satellite.As the phase untangling effect of GF-3 satellite data may be caused by parallel stripes induced by orbit error,a method using SRTM DEM elevation as the selected sample points and selecting 5 ground control points is proposed to eliminate these stripes and improve the inversion precision of deformation variables.The deformation information is similar to that from the data of Sentry 1 with developed technology.Therefore,as a new member of SAR satellites,GF-3 satellite has the capability of interferometry measurement with enough accuracy meeting the monitoring requirements.