【作者】 李辉；

【导师】 王霖郁；

【作者基本信息】 哈尔滨工程大学 ， 电子科学与技术， 2016， 硕士

【摘要】 干涉合成孔径雷达(InSAR)测量系统的一个最基本的应用就是地面高程的获得,其他的延伸的应用都是基于这一基本的高程信息的。地面高程信息的精度更是取决于相位解缠,因此研究InSAR信号处理中的相位解缠技术,提高缠绕相位的解缠精度显得十分重要。本文主要研究了 InSAR高程反演中的相位解缠问题。首先简单介绍了传统的相位解缠算法,并对相关理论做了详尽推导,分析和比较了各种传统算法的优缺点。针对其中的枝切法做进一步的优化和处理,其中包括通过用堆排序算法实现的质量图法和枝切法的结合,解决传统的枝切相位展开方法对于相干性差、信噪比小的区域,容易形成一个个独立的孤岛而无法解缠的缺陷。,在此基础上,本文还通过蚁群算法的应用,优化枝切法中的枝切线的放置,进一步提高整体算法的相位解缠的精度。本文最后还对该相位解缠的研究工作进行了展望。通过对传统相位解缠算法的深入研究,本文提出一系列的改进措施用来提升解缠算法在解缠过程中的精度和速度的表现,主要研究工作集中在以下几个方面:(1)针对基于质量图的相位解缠的指导方法要进行排序的操作,并且操作重复较大,相对比较耗时的问题,提出一种基于堆排序的质量图指导算法,降低了算法的时间复杂度,提升传统质量图算法的高效性。(2)针对传统的基于残差点的路径积分相位展开方法对于相干性差、信噪比小的区域,容易形成一个个独立的孤岛而无法解缠的缺陷,本文提出一种枝切法和质量图相结合的InSAR相位解缠的新算法。该算法即利用到了路径积分法的解缠速度快的特点,又利用到了质量图算法的相位解缠的有效性的特点,能有效处理大规模缠绕相位的解缠需求,相比于其他算法能得到更高的精度。(3)在枝切法的基础上,引入“近点”和蚁群算法优化传统枝切线的放置,从而有效减少枝切线的整体长度,而且使封闭区域数量明显减少。更多还原

【Abstract】 One of the most basic applications of interferometric synthetic aperture radar (InSAR)measurement system is to obtain the ground elevation, and the other extended applications are based on the basic elevation information. The accuracy of the ground elevation information is determined by the phase unwrapping. Therefore, it is necessary to carry out a detailed research on the key technology of InSAR signal processing.In this paper, we have carried out research on the interference processing of SAR, and mainly studied the phase unwrapping problem of height inversion in InSAR. First of all, the process of data analysis and processing of InSAR is briefly described, and several important steps are as following:image registration, ground effect removal, phase noise filtering,winding phase unwrapping, geographic information of encoding, etc.. And then, the process of elevation inversion is performed on the SARscape by data of ENVISAT ASAR, and the position and the importance of the phase unwrapping in the InSAR process are reflected. The traditional phase unwrapping algorithm is introduced in detail, and the relative theory is deduced, which is the theoretical basis for the improvement and innovation of the algorithm.To solve the problem that Quality map method must be sorted, and when the amount of data is large, the relative cost of time is high, a Quality map method based on heap sort is proposed.Compared with traditional Quality map method, it can make good optimization of the sorting time and reduce the time complexity of the algorithm, so the algorithm has better adaptability. the experimental results also verify the correctness and efficiency of the Quality map method with heap sorting algorithm in the phase unwrapping problem.To overcome the shortcomings of the easy to form a separate island without unwrapping,which is caused by the traditional path integral phase unwrapping method based on the residual points, a new algorithm of InSAR Phase Unwrapping based on the traditional path integral phase unwrapping and quality map method is proposed. Simulation and experimental data processing results show that the proposed algorithm can not only overcome the shortcomings of the branch cut method, which can not get the complete solution,but also surmount stop the diffusion of phase unwrapping error caused by the quality map method.The method can effectively deal with the requirements of large winding phase unwrapping.For traditional Goldstein’s branch cut method, residual path integral phase unwrapping method based on branch cuts is placed unreasonable. and obtaining path which easily to form a plurality independent island of unwrapping, and the whole length of the branch cuts is not very short. This paper presents an optimization branch tangent set of interference synthetic aperture radar phase unwrapping method. Firstly, introducing the concept of "closer" to the interferometric phase of pretreatment, most of the neighborhood can form comprehensive polar residues. Then through the shortest path connection using ant colony algorithm to solve the residuals. This method can not only effectively reduce the overall length of the branch cuts,but also significantly reduced the number of closed areas. The experimental results show that this method can realize the optimization of the branch cut set and has certain advantages on precision in phase unwrapping.更多还原