StaMPS-MTI技术在地面沉降监测中的应用

摘要

为了提高监测技术的空间采样率,基于永久散射体法(permanent scatters,PS)和短基线集法(small baseline subsets,SBAS)技术,同时考虑PS点、慢失相关滤波相位(slowly-decorrelationg filtered phase,SDFP)点的相位和幅度稳定性,对满足给定阈值的点相位进行加权平均,优化选取斯坦福永久散射体-多时相InSAR (stanford method for persistent scatterers-multi-temporal InSAR,StaMPS-MTI)技术的高相干点集.并使用SBAS技术的形变模型提取研究区的沉降量和沉降速率.在此基础上,分别利用PS、SBAS及StaMPS-MTI技术对北京市局部地区2007～ 2010年的29景ENVISAT ASAR数据进行处理,提取研究区2007 ～2010年的时序沉降情况及年平均沉降速率,对沉降结果进行了详细的对比和系统分析.理论研究和真实SAR数据实验结果均表明,StaMPS-MTI 技术获取了404 276个高相干点,空间采样率相较于PS技术提高了62.3％,相较于SBAS技术增加了129.4％,保证了监测结果的精度和可靠性.%In order to improve the spatial sampling rate of monitoring technologies,based on the methods of PS (permanent scatters) and SBAS (small baseline subsets),the point set of high coherence was optimally selected using StaMPS-MTI (stanford method for persistent scatterers-multitemporal InSAR) technology,and the phase and amplitude stability of PS and SDFP (slowly-decorrelationg filtered phase) points were considered to achieve the weighted average of the pixel phases which met a given threshold.The ground subsidence and mean subsidence rate of the test area were then extracted using the deformation model of SBAS technique.PS,SBAS and StaMPS-MTI technology were respectively used to process the ground displacement data of Beijing areas from 2007 to 2010 with 29 ENVISAT ASAR images,retrieving the temporal deformation sequence and the annual mean subsidence rate.The monitored subsidence results of the test area were compared and analyzed theoretically.Theoretical results and experimental results on real SAR data show that by using StaMPSMTI technology it can obtain 404 276 points of high coherence,and spatial sampling rate increases 62.3％ compared to PS technology,and 129.4％ compared to SBAS technology,which demonstrates the accuracy and reliability of monitored results.