面向矿区地表大形变的PSI/DInSAR与Offset-tracking深度融合方法研究

Concerning the bottleneck confronted while applying either PSI/DInSAR or Offset-tracking to large deformation monitoring in coal mining area, the research of this proposal will focus on the following three aspects. (1) Point-target-based Offset-tracking technology to improve the estimation efficiency and accuracy in area with low coherence, including point target identification and precisely automatic matching, offset component fitting caused by satellite orbit inconsistency and topography, of which the automatic precise matching between point targets is the key issue; (2) Precise co-registration between SAR images to restore the coherence otherwise lost due to large ground deformation, which consists of global polynomial construction based on the offset estimated with point-target-based Offset-tracking in stable area, and Regional Transformation Model (RTM) derived from the offset estimation in the corresponding deforming area; (3) According to the time-series analysis result from PSI/DInSAR, correct the deformation corresponding to range offset estimation from RTM to acquire the LOS deformation with higher accuracy. The ultimate goal is to realize the deep integration of PSI/DInSAR and offset tracking, so as to enhance the applicability and accuracy of SAR related technology while applied to large deformation monitoring in coal mining area. The achievements should provide technical supports for research on the rule of ground subsidence caused by high intensity coal mining in West China, which is of great importance for the ecologically vulnerable area to coordinate the development between coal resources exploitation and ecological environmental protection.

针对PSI/DInSAR和Offset-tracking监测矿区地表大形变面临的瓶颈，开展以下三方面的研究：（1）基于点目标的Offet-tracking技术及适用性评价，主要包括点目标的精确提取和自动匹配研究；（2）SAR影像精密配准研究，包括基于稳定区点目标偏移量构建全局配准多项式模型，和基于形变区点目标偏移量构建局部配准纠正模型，恢复SAR影像在地表大形变区域的相干性；（3）联合PSI/DInSAR时序分析技术，修正局部配准纠正模型中距离向偏移量估计对应的地表形变信息，实现对矿区地表形变的高精度监测。通过研究，实现PSI/DInSAR和Offset-tracking深度融合，提高卫星SAR影像相关技术对矿区地表大形变监测的适用性和监测精度。研究成果将为深入开展西部矿区高强度开采地表沉陷规律研究提供技术支撑，对生态脆弱区实现煤炭资源高效开发与生态环境保护协调发展具有重要意义。

我国是煤炭生产和消费大国，大量的煤炭资源开采带来一系列的环境和地质灾害问题。近年来，随着中东部地区煤炭资源逐渐枯竭和西部煤炭储量的查明，我国煤炭资源开发的重心向西部转移。加强矿区开采沉陷监测，对西部高强度开采地表沉陷规律研究、生态脆弱区环境保护和修复以及地质灾害预防具有重要意义。.本研究以西部高强度煤炭开采引起的大量级地表形变为对象，开展了以下研究工作：（1）在相干点目标提取的基础上，实现了基于点目标的偏移量跟踪技术在矿区开地表大形变监测中的应用，提出了基于不同尺寸互相关窗口循环逼近提取地表形变偏移量的方法；针对限制偏移量跟踪监测精度的影响因素，提出了对相干点目标进行分类处理的策略。利用工作面上方角反射器位置上的GPS/RTK测量成果对其进行精度评价，显示其精度可达0.07 pixel；（2）针对大量级地表形变引起的干涉图失相干现象，提出了融合偏移量跟踪监测结果进行SAR影响精配准的方法，有效恢复了形变区域角反射器位置上的相位相干性，在此基础上将偏移量跟踪探测结果与点目标响应技术融合，进一步提高了地表形变的估计精度，距离向精度达到1/20 pixel；（3）针对高噪声密集干涉条纹差分干涉图，提出了一种改进的自适应CKFPU算法，有效提高相位解缠精度；（4）通过查阅文献和现场调研，对神东矿区范围内已完成的超大工作面开采沉陷观测资料和有关研究成果进行收集汇总，为浅埋薄基岩煤层超大工作面开采沉陷规律的研究提供了基础。