發(fā)布時(shí)間：2018-05-17 03:22

  本文選題：星載SAR + 預(yù)處理��； 參考：《電子科技大學(xué)》2014年碩士論文

【摘要】：星載合成孔徑雷達(dá)具有全天時(shí)、全天候的對(duì)地觀測(cè)能力,在山區(qū)自然災(zāi)害的監(jiān)測(cè)和預(yù)警上有著重要的應(yīng)用,但是相干斑噪聲的干擾以及由山區(qū)地形起伏導(dǎo)致的幾何畸變現(xiàn)象將使星載SAR圖像在這方面的應(yīng)用大打折扣,本論文針對(duì)該這兩個(gè)問(wèn)題開展了對(duì)山區(qū)星載SAR圖像預(yù)處理的相關(guān)研究工作,主要包括了以下幾部分的內(nèi)容:首先,闡述了相干斑的產(chǎn)生機(jī)理及其統(tǒng)計(jì)特性,基于完全發(fā)育的相干斑模型,具體論述了三種相干斑抑制算法,即多視處理,LEE濾波和GAMMA-MAP濾波,分別將這幾種濾波算法應(yīng)用于TerraSAR-X數(shù)據(jù)的體育場(chǎng)場(chǎng)景圖和山區(qū)場(chǎng)景圖中,基于目視評(píng)估準(zhǔn)則和定量評(píng)估準(zhǔn)則對(duì)所得結(jié)果進(jìn)行分析比較,結(jié)果表明:這幾種濾波算法都對(duì)SAR圖像相干斑噪聲有較好的抑制作用,其中GAMMA-MAP算法對(duì)SAR圖像的結(jié)構(gòu)保持較好。其次,對(duì)山區(qū)星載SAR圖像的幾何畸變?cè)磉M(jìn)行了分析,簡(jiǎn)單介紹了兩種幾何校正方法:多項(xiàng)式校正法和共線方程校正法。重點(diǎn)闡述了基于SAR成像幾何的距離多普勒定位模型,在該模型的基礎(chǔ)上,分析研究了基于DEM的SAR圖像模擬,以及利用模擬SAR圖像的地形校正方法,本文以四川省阿壩州汶川縣映秀鎮(zhèn)區(qū)域作為實(shí)驗(yàn)區(qū),試驗(yàn)的數(shù)據(jù)為TerraSAR-X SSC數(shù)據(jù)、SRTM的90米DEM以及機(jī)載系統(tǒng)的25米DEM,試驗(yàn)結(jié)果表明:DEM的分辨率是對(duì)SAR圖像模擬的關(guān)鍵因素,而后向散射模型對(duì)其影響很小;對(duì)DEM數(shù)據(jù)的分形插值需要注意是否會(huì)引入錯(cuò)誤信息;基于DEM的模擬SAR圖像與真實(shí)圖像的紋理特征非常一致;基于模擬圖像的地形校正結(jié)果顯示該方法良好地消除了山區(qū)星載SAR圖像上的幾何畸變,恢復(fù)了山體特征。最后,通過(guò)編程實(shí)現(xiàn)了上述SAR圖像預(yù)處理方法,使用IDL語(yǔ)言搭建了山區(qū)星載SAR圖像預(yù)處理軟件平臺(tái),并展示了該軟件平臺(tái)的功能模塊以及部分處理界面。
[Abstract]:Spaceborne synthetic Aperture Radar (SAR) has an all-day, all-weather Earth observation capability and has important applications in monitoring and early warning of natural disasters in mountain areas. However, the interference of speckle noise and geometric distortion caused by terrain fluctuation in mountainous areas will greatly reduce the application of spaceborne SAR images in this field. In order to solve these two problems, this thesis has carried out the research on the preprocessing of spaceborne SAR images in mountainous areas, which includes the following parts: firstly, the mechanism of speckle generation and its statistical characteristics are described. Based on the fully developed speckle model, three speckle suppression algorithms, I. e., multi-view processing le filter and GAMMA-MAP filter, are discussed in detail. These filtering algorithms are applied to the stadium scene map of TerraSAR-X data and the mountain scene map, respectively. The results are analyzed and compared based on visual evaluation criteria and quantitative evaluation criteria. The results show that these filtering algorithms can suppress speckle noise of SAR images well, and GAMMA-MAP algorithm can keep the structure of SAR images better. Secondly, the principle of geometric distortion of spaceborne SAR images in mountainous areas is analyzed, and two geometric correction methods, polynomial correction and collinear equation correction, are briefly introduced. The range Doppler location model based on SAR imaging geometry is expounded. Based on this model, the simulation of SAR image based on DEM and the terrain correction method of simulated SAR image are analyzed and studied. In this paper, the Yingxiu Town area of Wenchuan County, Aba Prefecture, Sichuan Province is taken as the experimental area. The experimental data are 90m DEM of TerraSAR-X SSC data and 25m DEM of airborne system. The experimental results show that the resolution of the SAR image is the key factor in the simulation of SAR images. The backward scattering model has little effect on it; the fractal interpolation of DEM data should pay attention to the introduction of error information; the simulated SAR image based on DEM is very consistent with the texture feature of real image; The results of terrain correction based on simulated images show that the proposed method can eliminate the geometric distortion of spaceborne SAR images and recover the mountain features. Finally, the SAR image preprocessing method mentioned above is realized by programming, and the software platform of spaceborne SAR image preprocessing in mountain area is built by using IDL language, and the function module and some processing interface of the software platform are shown.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：TN957.52

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 王曉軍,孫洪,管鮑;SAR圖像相干斑抑制濾波性能評(píng)價(jià)[J];系統(tǒng)工程與電子技術(shù);2004年09期

2 朱彩英,徐青,吳從暉,池天河,何建邦;機(jī)載SAR圖像幾何糾正的數(shù)學(xué)模型研究[J];遙感學(xué)報(bào);2003年02期

相關(guān)博士學(xué)位論文 前1條

1 陳爾學(xué);星載合成孔徑雷達(dá)影像正射校正方法研究[D];中國(guó)林業(yè)科學(xué)研究院;2004年

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本文編號(hào)：1899682