星载SAR影像定位与InSAR中应用有理函数模型的研究

发布时间：2018-03-05 06:34

本文选题：星载SAR影像　切入点：距离-多普勒模型　出处：《解放军信息工程大学》2013年硕士论文　论文类型：学位论文

【摘要】：星载SAR系统的技术水平日益先进，星载SAR影像的空间分辨率和时间分辨率也不断提高，在对地观测领域扮演着越来越重要的角色。星载SAR影像的无控定位技术可以获取测绘困难地区重点目标的三维坐标，是星载SAR影像的重要应用之一；有理函数模型(Rational Funtion Model, RFM)在光学遥感影像和SAR影像的摄影测量处理中得到了广泛应用，将RFM引入星载InSAR数据处理流程，也具有重要的理论和实践意义。本文以高分辨率SAR影像的应用为主线，分析了SAR影像的严密几何模型和通用几何模型，分别对稀少(无)控制条件下星载SAR影像的目标定位技术和RFM在InSAR数据处理流程中的应用进行了研究，主要工作包括以下内容： 1)从载荷技术、成像特点和应用技术三个方面，总结了SAR和InSAR技术以及有理函数模型的研究和发展现状，确定了论文的研究目的和意义。 2)基于距离-多普勒模型，系统阐述了星载SAR影像的无地面控制信息下的定位原理。利用高分辨率TerraSAR影像进行了相关实验，无控定位精度在方位向达到了70m，距离向达到了50m。利用少量控制点精化模型定向参数，将定位精度提高至方位向25m，距离向20m。提出了一种新的目标高程归化至赤道半径的计算方法，通过推导和仿真，分析得出在高纬度地区，地形起伏将产生最大60米左右的定位误差。 3)从InSAR基本几何原理出发，建立了InSAR严密几何模型和通用几何模型。对比了光学摄影测量和InSAR的共性和差异，阐明了将RFM引入InSAR数据处理的可行性。 4)对InSAR干涉影像对，分别建立了用于主辅影像配准、去平地效应和相位-高程转换的RFM方程；基于全球低分辨率DEM，设计了一种无需初值和迭代的RFM参数求解方法。以SRTM模拟干涉数据和天山地区模拟干涉数据，进行了相位-高程转换实验，，二阶RFM的替代精度分别达到了0.1941米和0.000014米。为解决RFM参数求解时的病态问题，分别采取了直接计算方法改正和间接误差补偿改正两种方法，SRTM模拟数据直接计算改正的精度提高了17.9%，间接误差补偿的精度提高了44.8%。
[Abstract]:The technology level of spaceborne SAR system is becoming more and more advanced, and the spatial and temporal resolution of spaceborne SAR image is also improving. It is one of the important applications of spaceborne SAR images to obtain the 3D coordinates of the key targets in difficult areas by using the uncontrolled localization technology of spaceborne SAR images, which plays an increasingly important role in the field of Earth observation. Rational Funtion Model (RFM) has been widely used in photogrammetric processing of optical remote sensing and SAR images. It is also of great theoretical and practical significance to introduce RFM into spaceborne InSAR data processing process. Based on the application of high-resolution SAR images, the strict geometric model and the general geometric model of SAR images are analyzed in this paper. The target location technology of spaceborne SAR images and the application of RFM in InSAR data processing are studied respectively under rare (no) control conditions. The main work includes the following contents:. 1) the research and development status of SAR and InSAR technology and rational function model are summarized from three aspects of load technology, imaging characteristics and application technology, and the purpose and significance of this paper are determined. 2) based on the range-Doppler model, the positioning principle of spaceborne SAR images without ground control information is systematically expounded. Experiments are carried out using high-resolution TerraSAR images. The accuracy of uncontrolled positioning reaches 70 m in azimuth direction and 50 m in distance direction. By using a small number of control point refinement model orientation parameters, the positioning accuracy is raised to 25 m in azimuth direction and 20 m in distance direction. A new method for calculating the elevation of target to equatorial radius is proposed. Through derivation and simulation, it is concluded that the maximum positioning error is about 60 meters in the high latitude area. 3) based on the basic geometry principle of InSAR, the strict geometric model of InSAR and the general geometric model of InSAR are established, the commonness and difference between optical photogrammetry and InSAR are compared, and the feasibility of introducing RFM into InSAR data processing is expounded. 4) for the InSAR interference image pair, the RFM equations are established for the main and auxiliary image registration, levelling effect and phase-height conversion. Based on global low resolution demm, a method of solving RFM parameters without initial value and iteration is designed. Using SRTM simulated interference data and Tianshan region simulated interference data, phase to height conversion experiments are carried out. The substitution accuracy of second-order RFM is 0.1941m and 0.000014m respectively. In order to solve the ill-posed problem of RFM parameters, Two methods, direct calculation correction and indirect error compensation correction, are adopted to improve the accuracy of direct calculation correction of SRTM simulation data and the accuracy of indirect error compensation by 17.9% and 44.8% respectively.
【学位授予单位】：解放军信息工程大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P228

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