多基线INSAR技术应用若干难点问题研究

Multi-baseline SAR interferometry (INSAR) has become an issue of remote sensing technology application research since it can overcome inherent defect of conventional INSAR. It is difficult for the conventional algorithms to estimate effectively the interferogram with complex fringe and with dense fringe since the adaptability and the stability of the conventional algorithms isn't strong enough. This project will firstly focus on the analysis of the relationship between the system baseline structure and the measurement accuracy for acquiring the optimal baseline vector.Secondly, a novel multi-baseline phase estimate algorithm based on the Kalman filter (KF) is put forward to estimate effectively the interferogram with complex fringe and with dense fringe. Further, a multi-baseline phase estimate algorithm based on the particle filter (PF) is proposed to solve nonlinear and non-stationary phenomenon of INSAR image by combining a PF with an omni-directional local frequency estimator. Finally, simulation and real data processing results validate the effectiveness of the proposed methods. The innovative achievements in the multi- baseline phase estimation technology and the optimal baseline vector selection method are expected to carry out this research project, which will extend INSAR technology application prospect.

多基线INSAR测量是当前INSAR技术应用研究热点。本项目将针对多基线INSAR技术应用的若干难点问题展开研究，重点分析系统基线构成与测高精度之间关系，研究多基线INSAR最优基线矢量构建方法；针对现有方法稳健性和适应性不够，难以有效解决条纹复杂且密集的干涉图相位估计问题，通过建立干涉相位的动态方程，提出基于KALMAN滤波的多基线INSAR相位估计方法；研究克服非线性和非平稳现象的多基线相位估计方法，进一步提出结合全方位局部频率估计技术和粒子滤波算法的多基线INSAR相位估计方法，达到提高干涉相位估计精度的目标。最后，完成实测和模拟INSAR相位估计试验及目标高程反演实验，验证算法的有效性。开展本项目的研究，有望在多基线INSAR相位估计算法、多基线INSAR最优基线矢量构建方法等方面获得创新性成果，具有良好的应用前景。

本课题研究了多基线最小二乘以及多基线迭代等框架下基线矢量的构建；针对多基线INSAR相位估计的问题，提出了基于扩展卡尔曼滤波(EKF)的多基线SAR干涉相位估计方法，结合修正矩阵束模型（AMPM）、量化跟踪策略与EKF算法，提出了高效的多基线EKF干涉相位估计方法，进一步研究了基于无味卡尔曼滤波（UKF）的多基线SAR干涉相位估计方法；针对非线性和非平稳现象对多基线SAR干涉相位估计的影响问题，结合无味粒子滤波和传统路径跟踪策略，提出了基于无味粒子滤波的多基线SAR干涉相位估计方法，进一步结合扩展粒子滤波（EPF）算法、AMPM模型以及量化路径跟踪策略，提出基于量化跟踪策略的多基线EPF干涉相位估计算法；此外，课题对适用于三基线以上的多基线INSAR相位估计进行了研究，提出了基于频率补偿的多基线SAR干涉相位估计算法。项目所开展的研究有利于在多基线INSAR系统构建、多基线INSAR相位估计算法等方面获得获得较好的成果，具有良好的应用前景。