Rational function modeling for spaceborne SAR datasets     

Lu Zhang  Xueyan HeTimo Balz  Xiaohong WeiMingsheng Liao 《ISPRS Journal of Photogrammetry and Remote Sensing》2011,66(1):133-145

As a kind of generic sensor model, the rational function model (RFM) has been widely used in geometric processing of optical images, but has not yet been applied to SAR datasets. In this article the feasibility and methodology of rational function (RF) modeling for SAR datasets are investigated. After a review of the mathematic formulation of the RF model and the Range-Doppler model for SAR systems, the feasibility of applying RFM to SAR datasets is analyzed. Afterwards a two-stage approach is proposed as the key technique for SAR RF modeling to solve unknown parameters of RFM in a fast and unbiased way. The effectiveness and advantages of this approach are demonstrated by comparisons with traditional methods. Experimental results obtained for various spaceborne SAR datasets of different processing levels show that RFM is a suitable replacement of the rigorous Range-Doppler model for spaceborne SAR images. Furthermore, the impacts of several factors including the control point grid size, the number of elevation layers, and the orbit precision on SAR RFM solutions are evaluated quantitatively. The results show that the number of elevation layers is a key factor in SAR RF modeling, and its value should be set carefully according to terrain conditions of study areas. Finally, potential applications of SAR RFM are discussed in brief.  相似文献   

遥感图像融合技术在潮间带地形提取中的应用   总被引：2，自引：0，他引：2  

余连生  李智勇  文贡坚  杜春 《测绘学报》2011,40(5)

针对潮间带地形资料的缺乏和提取手段的贫乏,提出一种提取潮间带地形的新思路。利用同一潮汐周期不同时相的SAR与全色遥感图像,采用平移不变离散小波变换算法进行图像融合,并采用一种新的融合规则。图像的低频部分采用基于边缘提取的加权规则,高频部分采用绝对值最大原则。对比其他算法,融合结果既能突出潮间带形状,又能突出海岸线特征及近岸地形,更便于后续目视解译。对实际图像的试验结果表明,该方法取得了较好的效果。  相似文献   

一种基于证据理论的多极化SAR图像分割方法     

邓少平  李平湘  张继贤  黄国满  赵争 《测绘科学》2011,36(6):32-34,31

本文提出了一种基于证据理论的融合像素信息和上下文信息的多极化合成孔径雷达(SAR)图像分割方法.D-S证据理论是一种不确定性推理方法.基于D-S的SAR影像分割方法将像素信息和上下文信息看作两类证据,先对高度平滑后的影像作初始的过分割,然后基于D-S理论对初始分割图斑的边界进行迭代修正,最后再融合两类证据对初始分割的图...  相似文献   

多波段高分辨率星载合成孔径雷达成像处理方法研究     

井长青  张永福 《北京测绘》2011,(2):30-32,26

星载合成孔径雷达（SAR）是一种工作在微波波段的主动式遥感器,它综合运用合成孔径技术、脉冲压缩技术和数据处理技术,采用较短的天线就能够获得方位和距离两个方向的高分辨率雷达图像。研制星载SAR系统的目的是获得具有一定测绘带宽和一定分辨率的地面目标图像,传统SAR模式不能同时满足高分辨率及较宽测绘带的要求。本文主要研究了多...  相似文献   

Building extraction from high resolution SAR imagery in urban areas     

Yansheng Dong  Hongping Chen  Deyong Yu  Yanzhong Pan  Jingshui Zhang 《地球空间信息科学学报》2011,14(3):164-168

  相似文献   

Evaluation of DC, FDEM and IP resistivity methods for imaging perched saltwater and a shallow channel within coastal tidal flat sediments   总被引：1，自引：0，他引：1  

Mohamed Attwa  Thomas GüntherMichael Grinat  Franz Binot 《Journal of Applied Geophysics》2011,75(4):656-670

Presently, electrical resistivity methods are applied in a wide variety of geological and environmental site investigations. Geologically, the coastal tidal flat sediments formed shallow channel-like features at the northern part of Germany. Three geoelectrical methods are applied to image the near surface sediments including a shallow conductive zone within the tidal deposits at the North Sea coast. These methods, direct current (DC) resistivity, frequency domain electromagnetic (FDEM) and spectral induced polarization (SIP), are evaluated to show which one can provide the required spatial resolution under study area conditions. This evaluation also includes a synthetic modeling to assess the DC resistivity imaging technique.The results constitute an encouraging example using these geophysical methods in characterizing the coastal aquifers. The inversion results show that the subsurface resistivity distribution of tidal sediments can change rapidly within a short distance. A thin high conductive layer is observed above the peat and clay layers reflecting a perched saltwater. The 2D IP section shows that the perched saltwater is restricted to patched forms above an impermeable layer of clay. According to the IP images the boundaries of the clay layer are recognized with a good resolution due to the high membrane polarization of the clays. The EM and DC profiles show a shallow channel-like feature within tidal deposits. In this paper, the best FDEM field parameters and the role of EM in lithologic studies are emphasized. Two main limitations can be observed from DC synthetic modeling: (a) A smearing in the lower boundary of the perched saltwater; (b) an amplification of the lateral effect of the highly conductive layer. These limitations decrease the resolution of DC imaging for accurate defining our targets. Because the IP response depends on microgeometry, fluid chemistry and saturation, the 2D IP results demonstrate the suitability of this method to characterize the tidal deposits in the coastal area with a good resolution. In this study, the success of SIP method supports further investigations into studying the hydraulic parameters of tidal deposits in this area. The obtained results during this investigation provide an overview of the coastal aquifer and they can serve as a basis for refining the conceptual model of morphological elements and sedimentary sequences of the coastal tidal flat.  相似文献   

基于小基线DInSAR技术监测太原市2003～2009年地表形变场   总被引：7，自引：0，他引：7       下载免费PDF全文

吴宏安  张永红  陈晓勇  Lu Zhong  都洁  孙中惠  孙广通 《地球物理学报》2011,54(3):673-680

基于高相干点目标反演缓慢地表形变已成为当前DInSAR技术的研究热点.本文通过融合PS方法和相干目标法优点,采用小基线DInSAR技术提取城市地表形变场,并重点分析了地表线性形变的反演.在此基础上,以太原市为研究区,利用23景ENVISAT ASAR影像,提取了该市2003～2009年的地表形变场.研究结果表明:(1)...  相似文献   

基于乘积模型的极化SAR滤波   总被引：1，自引：0，他引：1  

邓少平  李平湘  张继贤  黄国满 《武汉大学学报(信息科学版)》2011,36(10):1168-1171

提出了一种基于乘积模型的极化SAR滤波方法。首先基于乘积模型分离纹理信息和极化信息,然后分别独立地进行滤波,最后再合成协方差矩阵。实验表明,本方法有效可行,有较好的极化保持性能。  相似文献   

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李陶  张诗玉  周春霞 《大地测量与地球动力学》2007,27(1):59-64

??L ^P ????????￡?????????λ???????????????????о?????????????3???????????????????????Bam?????????SAR??????????????????????????:Goldstein?????????Ч???????е??????????,??????????????Ч??????????????????????L ¹?????????????????????????????Ч?????L ²?????????????????????????Ч?????L ⁰????????????????????????????????????????????????????????  相似文献   

集安市团结区地质特征及物探异常分析     

徐良  衣吉伟  刘红香 《吉林地质》2013,(4):103-105

通过对集安市团结区地质特征的介绍,结合本区开展的物探激电中梯测量所取得的成果,确定该区的找矿方向。实践证明地质、物探方法相结合对于地质找矿具有重要意义。  相似文献