阵列钻孔雷达微弱目标成像技术研究

The array borehole radar imaging is the key technology to obtain the information of abnormal media in nonuniform subsurface environment, which is of important academic research significance and great engineering value in the fields of cavity and fracture detection, hydrogeology, mineral exploration and so on. Based on the Stolt migration method and reverse time migration method, the problems of high sampling freedom data processing, wave field singular value decomposition filtering and target scattering wave field matching are studied to implement the high-efficiency and high-resolution imaging of subsurface weak targets with array borehole radar. Firstly, considering the high-efficiency imaging demand of array borehole radar, the high sampling freedom data processing and geometric-constraint-based wave field correction technologies are studied, and the array borehole radar Stolt migration imaging method with high efficiency is proposed. Then, considering the high-resolution demand of array borehole radar, the wave field singular value decomposition filtering and target scattering wave field matching technologies are studied, and the array borehole radar reverse time migration imaging method with high resolution is proposed. Finally, the nonuniform subsurface weak target detection model is established, the simulation experiments are designed to analyze the proposed theoretical methods, and the array borehole radar field experiments are conducted to validate the practicability of the proposed methods.

阵列钻孔雷达成像是获取非均匀地层环境中异常介质信息的关键技术，在空洞和裂缝探测、水文地质学及矿藏勘探等领域具有重要的学术研究意义和巨大的工程应用价值。本项目以Stolt偏移技术和逆时偏移技术为基础，研究高采样自由度数据处理、波场奇异值分解滤波及目标散射波场匹配等问题，实现阵列钻孔雷达对微弱目标的高效率和高分辨率成像。首先，针对阵列钻孔雷达的高效率成像需求，研究高采样自由度数据处理技术和几何约束关系波场修正技术，提出阵列钻孔雷达Stolt偏移高效率成像方法。然后，针对阵列钻孔雷达的高分辨成像需求，研究波场奇异值分解滤波技术和目标散射波场匹配技术，提出阵列钻孔雷达逆时偏移高分辨成像方法。最后，建立非均匀地层微弱目标探测模型，设计仿真实验对本项目的理论方法进行分析，利用阵列钻孔雷达外场实测数据对方法的实用性进行验证。

本项目针对阵列钻孔雷达在非均匀地层介质环境中的高分辨和高效率目标成像问题展开研究，以Stolt偏移技术和逆时偏移技术为基础涉及阵列钻孔雷达Stolt偏移高效率成像技术、阵列钻孔雷达逆时偏移高分辨成像技术以及阵列钻孔雷达成像方法验证等内容，突破阵列雷达回波空频域约束分析和前后向波场匹配等关键科学问题，形成一系列创新研究成果，包括基于高采样自由度的Stolt偏移成像、基于几何约束关系的Stolt偏移成像、基于奇异值分解滤波的逆时偏移成像、基于目标散射波场匹配的逆时偏移成像、地层传播介质建模以及基于电磁计算平台的仿真验证等方法，发表学术论文8篇，其中在IEEE T-GRS等国际学术期刊发表SCI检索学术论文3篇；在IEEE Radar Conference等国际会议发表EI检索学术论文5篇；申请发明专利5项。该项目的研究提高了我国地下遥感技术的基础研究水平和自主创新能力，相关成果在地下空洞和裂缝探测、水文地质学及矿藏勘探等领域具有重要的学术研究意义和工程应用价值。