永久散射体探测与雷达差分干涉建模及其应用

发布时间：2018-06-15 01:39

本文选题：永久散射体探测 + 差分干涉合成孔径雷达　；参考：《辽宁工程技术大学》2013年博士论文

【摘要】：目前,永久散射体干涉合成孔径雷达(Persistent Scatterer Synthetic Aperture Radar Interferometry, PSI)技术已成为国际雷达遥感界的研究热点之一,在地表形变监测方面已表现出极大的应用潜力。从被提出至今,PSI技术在国内的发展还不足14年,这段时间内虽然有许多研究者对PSI技术进行了大量的理论和实验研究,并取得了广泛的应用,但就地表形变监测而言,PSI技术的应用尚没有进入真正意义上的业务化运行阶段。主要受制于目前的SAR影像数据获取困难,同时有些关键技术还有待进一步改进和完善,如永久散射体(Persistent Scatterer, PS)的有效识别与选取、干涉对的优化组合方式和形变量的高精度估算等。论文以PSI技术为研究对象,旨在改善雷达干涉技术在区域地表形变监测中的精度和可靠性。具体来说,研究内容包括： 1、比较和分析了现有PSI技术在地表形变监测方面的应用中采用的数学模型和数值计算算法,对现有PSI技术监测地表形变的实用化数据处理流程进行了总结。 2、研究了PSI数据处理中所涉及的永久散射体识别与选取问题,形成了永久散射体识别与选取的实用化数据处理流程和方法,提出并实现了一种改进的PS探测算法,最后利用实际的SAR影像进行了有针对性的数值试验,对该方法的有效性和可行性进行验证,并在此基础上,对PSI建模时采用的各相位分量的空间相关特性进行了详细的分析。 3、时序SAR影像的干涉处理是PSI技术应用于地表形变监测的重要环节之一,而SAR影像的干涉组合方式直接影响着干涉相位的质量。为了实现干涉对的优化组合,论文在常用干涉组合方式的基础上提出了一种新的干涉组合方式,即在考虑空间基线和时间基线阈值的同时,考虑各干涉对的相位噪声限制。结果表明,相比于已有的干涉组合方式,论文提出的干涉组合方式获取的干涉对数量最少,PS个数最多,以水准实测数据进行检核,PSI年沉降速率中误差为±3.89mm/yr,证实了该干涉组合方式的有效性和可靠性。 4、应用高分辨率PSI技术,以上海地区地表沉降为研究对象,开展了PSI在地表形变监测中的应用实验。结果表明：(1)研究区域内最大沉降速率达-47mm/yr,平均沉降速率为-16.96mm/yr,地表沉降比较明显；(2)在该阶段存在3个明显的沉降中心,即罗泾镇、虹口足球场和闵行区；(3)现今上海地表沉降随着城市建设的发展向南、西南、东南逐步扩展；(4)水准数据验证了监测结果,精度可达±6mm/yr,表明PSI技术在地表形变监测中的应用是可靠的。
[Abstract]:At present, Persistent synthetic Aperture Radar Interferometric (PSIY) technology has become one of the research hotspots in the field of international radar remote sensing, and has shown great application potential in the field of surface deformation monitoring. PSI technology has been developed in China for less than 14 years since it was proposed. During this period, many researchers have done a lot of theoretical and experimental research on PSI technology, and have obtained extensive application. However, the application of PSI technology has not entered the operational stage in real sense in terms of surface deformation monitoring. At the same time, some key technologies need to be further improved and improved, such as the effective identification and selection of persistent scatterers (PSs). Optimal combination of interference pairs and high precision estimation of shape variables. In order to improve the accuracy and reliability of radar interferometry in regional surface deformation monitoring, PSI technology is taken as the research object in this paper. The main contents are as follows: 1. The mathematical models and numerical algorithms used in the application of PSI technology in surface deformation monitoring are compared and analyzed. The practical data processing flow of PSI technology for monitoring surface deformation is summarized. 2. The identification and selection of permanent scatterers involved in PSI data processing are studied. A practical data processing flow and method for the identification and selection of permanent scatterers is formed. An improved PS detection algorithm is proposed and implemented. Finally, a targeted numerical experiment is carried out using actual SAR images. The validity and feasibility of the method are verified. The spatial correlation characteristics of each phase component used in PSI modeling are analyzed in detail. 3. Interference processing of sequential SAR image is one of the most important links in the application of PSI technology to surface deformation monitoring. The interferometric combination of SAR images directly affects the quality of the interferometric phase. In order to realize the optimal combination of interference pairs, a new method of interference combination is proposed based on the common interference combination methods, that is, considering the threshold of spatial baseline and time baseline, the phase noise limitation of each interference pair is considered at the same time. The results show that the number of interference pairs obtained by the proposed interference combination method is the most than that of the existing interference combination method. The median error of annual settlement rate of PSI is 卤3.89 mm / yr. the validity and reliability of the interference combination method are confirmed. 4. Using high resolution PSI technique, the ground subsidence in Shanghai area is taken as the research object. The application experiment of PSI in surface deformation monitoring is carried out. The results show that the maximum subsidence rate is -47 mm / yr, the average subsidence rate is -16.96 mm / yr, and the surface subsidence is obvious at this stage) there are three distinct subsidence centers in this stage, namely Luojing Town, Hongkou Football Field and Minhang District; (3) with the development of urban construction, the ground subsidence in Shanghai is gradually expanding to the south, southwest and southeast. The monitoring results are verified by the leveling data, and the accuracy can reach 卤6mm / yr. it shows that the application of PSI technology in surface deformation monitoring is reliable.
【学位授予单位】：辽宁工程技术大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：P225.2;P237

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