基于导航卫星的SS-D-InBSAR高精度地表形变监测技术研究

Under the financial support of youth science foundation project, Progressive results have been acquired in the field of imaging and differential interferometry processing of SS-D-InBSAR. First of all, the imaging algorithm was proposed for the BiSAR systems with long integration time and severely asymmetric topography, and had been verified by the imaging processing of the dataset from the real bistatic SAR experiments. Secondly, with the developing of experiment of surface detection, the processing algorithm of interferometry was derived and did a good job in the real data of SS-D-INSAR, which indicated the applicative possibility of the proposed algorithm. At the meantime, 14 scientific articles have been published, 8 of which were embodied by SCI and 6 by EI. Furthermore, 10 patents were composed, and 4 of them were authorized. Based on the fruitful outcome of youth science foundation project, we shall keep on the research of surface change detection of SS-D-INBSAR. Firstly, in order to solve the impact of the defocus on the SAR image because of the planar scene assumption, the DEM of the target area should be into the consideration of the technology of imaging algorithm. Secondly, the technology of high synthetic resolution in range and azimuth direction should be derived in view of the restriction of image resolution, which is introduced by the narrow band-width and observation angle of the single navigation satellite. Lastly, considering the influence of low SNR, which may have a bad effect on change detection and that only the change detection under the sight of beam could be gained by mono-source differential interferometry processing, we could focus on the research of muti-dimensional differential interferometry processing with multi-angle of multi-navigation satellite.

青年科学基金项目已在基于导航卫星的SS-D-InBSAR成像处理和差分干涉处理方面取得了阶段性进展:(1)提出了长合成孔径时间和非对称构型下的成像处理算法，通过了实验数据处理验证；(2)提出了基于导航卫星的SS-D-InBSAR差分干涉处理算法，地面实验结果验证了基于导航卫星的SS-D-InBSAR监测地表形变的可行性。共发表8篇SCI收录论文和6篇EI收录论文，获得4项授权专利，申请6项授理专利。拟继续开展基于导航卫星的SS-D-InBSAR高精度地表形变监测技术研究：(1)为解决SS-D-InBSAR非平面的聚焦面对成像处理的影响，研究基于DEM参考面的成像处理技术；(2)为突破导航卫星小带宽信号和单颗卫星有限的对地观测角度对图像分辨率的限制，研究二维合成高分辨成像技术；(3)为解决低信噪比对形变精度影响和单源差分干涉处理只能获取波束视线方向形变的问题，研究多维度差分干涉联合处理技术。

基于导航卫星的星地双基地差分干涉合成孔径雷达（SS-D-InBSAR）具有发射信号时空连续覆盖、便于干涉、部署灵活以及低成本的特点，在进行局部区域的连续形变监测方面具有巨大的潜力，能够为滑坡等地质灾害的预防提供技术支持，具有广阔的应用前景。经过4年的实施，围绕基于导航卫星的SS-D-InBSAR成像处理、二维合成高分辨、多源差分干涉联合处理技术等开展理论和实验研究，取得了多项突破，按预期完成了研究计划。.本项目主要取得以下研究成果：.一、开展了基于DEM信息的导航卫星双基地SAR成像算法的理论和实验研究。提出了基于激光雷达高程信息获取的导航卫星双基地SAR非平面成像方法，利用激光雷达测量场景的高程点云，利用高程数据构建成像曲面，实现了非平面场景的导航卫星双基地SAR成像；.二、开展了基于导航卫星的SS-D-INBSAR二维合成高分辨的理论和实验研究。提出了基于多星座多角度融合的SAR图像二维高分辨合成方法，通过多星座多角度图像融合处理，实现了场景目标连续轮廓的获取以及SAR图像二维分辨率的改善，显著提高了图像质量；.三、开展了基于强点目标的导航卫星双基地SAR多星座差分干涉三维形变监测方法的理论和实验研究。提出了基于先验信息的多角度SAR强散射点识别及图像配准处理方法和多角度差分干涉SAR三维形变反演方法，实现了精度优于5mm的三维形变反演；.四、开展了基于场景目标的导航卫星双基地差分干涉SAR形变反演方法的理论和实验研究。提出了基于多卫星时空基线优化的导航卫星双基地差分干涉SAR形变监测方法，解决了导航卫星重轨空间基线特性约束下的高程相位、残余大气和通道相位的估计与补偿等一系列难题，实现了场景形变信息的反演。.项目实施过程中，在本领域国内外重要期刊（IEEE TGRS, GRSL等）和国际会议（IEEE/IET Radar Conf.等）上发表论文11篇，其中SCI论文4篇，EI论文7篇。申报发明专利7项（授权5项），培养研究生11名。