采用过采样方法提高SAR图像相干性,使研究区域的干涉条纹更加清晰.以唐山矿区为例,采用过采样方法获得了6对矿区沉降干涉图,并计算了该区域的地面沉降时间序列.结果表明,唐山部分矿区在2004年11月到2005年4月间存在快速的沉降,最大沉降速率达到2 398 mm/a.
The authors use oversampling method to improve the coherence of SAR images, which makes the fringes of the studied area clearer.By using this method, the authors process 6 pairs of interferograms and derive the time series of mining subsidence.The results show that some mines in Tangshan have been subsiding rapidly from November 2004 to April 2005 with the maximum rate of 2 398 mm/yr.