程宇峰，金淑英，王密，等

·推薦論文摘要·

一種光學(xué)遙感衛(wèi)星多相機(jī)成像系統(tǒng)的高精度影像拼接方法

程宇峰，金淑英，王密，等

提出一種基于虛擬大相機(jī)的光學(xué)遙感衛(wèi)星多相機(jī)系統(tǒng)成像數(shù)據(jù)的拼接方法，實現(xiàn)多相機(jī)影像的高精度拼接。該方法根據(jù)各單相機(jī)的幾何成像模型，構(gòu)建虛擬大相機(jī)的幾何成像模型；利用坐標(biāo)正算、反算過程對各單相機(jī)影像進(jìn)行間接法幾何糾正，得到虛擬大相機(jī)圖像坐標(biāo)系下的各虛擬單相機(jī)影像；將各虛擬單相機(jī)影像基于影像坐標(biāo)信息拼接處理后得到最終的虛擬大相機(jī)影像。該方法利用虛擬大相機(jī)實現(xiàn)多相機(jī)影像的高質(zhì)量拼接，為后期處理提供了與之相對應(yīng)的高精度有理函數(shù)模型，可用于不同數(shù)量、不同分辨率的多相機(jī)系統(tǒng)實現(xiàn)全自動智能地面預(yù)處理。

遙感；光學(xué)遙感衛(wèi)星；高精度拼接；虛擬大相機(jī)；多相機(jī)系統(tǒng)；預(yù)處理

來源出版物：光學(xué)學(xué)報,2017,37(8): 0828003

聯(lián)系郵箱：金淑英，jsy@whu.edu.cn

吉林一號輕型高分辨率遙感衛(wèi)星光學(xué)成像技術(shù)

徐偉，金光，王家騏

摘要：為了實現(xiàn)吉林一號光學(xué)遙感衛(wèi)星輕量化設(shè)計與高分辨率多光譜多模式成像，采用星載一體化設(shè)計理念及敏捷多模式成像策略，完成了吉林一號衛(wèi)星的指標(biāo)、方案及關(guān)鍵技術(shù)的設(shè)計與在軌多模式光學(xué)成像。吉林一號整星的質(zhì)量為450 kg，有效載荷比高達(dá)40%，機(jī)動能力達(dá)2.1(°)/s，可實現(xiàn)大側(cè)擺、同軌立體與條帶拼接等多模式成像，結(jié)合星上800gB的FLASH存儲能力和X波段雙通道600 Mbps的數(shù)據(jù)傳輸能力，衛(wèi)星每天可獲取近150000km2的圖像數(shù)據(jù)。吉林一號輕型高分辨率光學(xué)衛(wèi)星于2015年發(fā)射入軌，運(yùn)行在656km太陽同步軌道，地面全色和多光譜分辨率分別優(yōu)于0.72 m和2.88 m，滿足多行業(yè)應(yīng)用及商業(yè)化運(yùn)營的需求。

關(guān)鍵詞：光學(xué)遙感；星載一體化；吉林一號；多模式成像；輕型高分辨

來源出版物：光學(xué)精密工程,2017,25(8):1969-1978

聯(lián)系郵箱：徐偉，xwciomp@126.com

氣溶膠衛(wèi)星遙感產(chǎn)品在林火檢測中的適用性

王研峰，張婕，章煥，等

摘要：森林火災(zāi)導(dǎo)致火點周圍氣溶膠光學(xué)厚度（AOD）發(fā)生顯著變化，可利用MODIS氣溶膠產(chǎn)品作為識別火點的輔助手段。通過對比火點周圍MODIS C510km、C63km、C610km氣溶膠產(chǎn)品的有效樣本數(shù)、空間分布特征來評估不同版本氣溶膠產(chǎn)品應(yīng)用于火災(zāi)煙羽檢測的可行性，同時對比在火點32方位角條件下AOD的積累效應(yīng)對煙羽敏感性的差異。結(jié)果表明，MODIS C63km氣溶膠產(chǎn)品能較準(zhǔn)確地表征林火伴生的煙羽特征，C610km和C510km產(chǎn)品效果較差。C63km產(chǎn)品在以火點為中心，擴(kuò)散半徑為24km時，32方位角累積AOD比值對煙羽檢測敏感，C510km和C610km產(chǎn)品對煙羽檢測的敏感性較差。

關(guān)鍵詞：氣溶膠產(chǎn)品；林火檢測；適用性

來源出版物：蘭州大學(xué)學(xué)報：自然科學(xué)版,2017, 53(1):101-105

聯(lián)系郵箱：王研峰，wangyanfeng_1986@163.com

衛(wèi)星遙感地表溫度降尺度的光譜歸一化指數(shù)法

李小軍，辛?xí)灾?，江濤，?/p>

摘要：針對衛(wèi)星遙感技術(shù)監(jiān)測地表溫度（land surface temperature，LST）存在時空分辨率矛盾這一難題，以TsHARP溫度降尺度算法為基礎(chǔ)，根據(jù)地表覆蓋類型的不同，分別選擇與 LST相關(guān)性更好的光譜指數(shù)（歸一化植被指數(shù)，NDVI；歸一化建造指數(shù)，NDBI；改進(jìn)的歸一化水體指數(shù)，MNDWI；增強(qiáng)型裸土指數(shù)，EBSI）提出了新的轉(zhuǎn)換模型，并從定性和定量兩個角度評價了TsHARP法和新模型的降尺度精度。結(jié)果表明：兩種模型在提高 LST空間分辨率的同時又能較好地保持MODIS LST影像熱特征的空間分布格局，消除了原始1km影像中的馬賽克效應(yīng)，兩種模型均能夠達(dá)到較好的降尺度效果；全局尺度分析表明，不管是在降尺度結(jié)果的空間變異性還是精度方面，本文提出的模型（RMSE：1.635℃）均要優(yōu)于 TsHARP法（RMSE：2.736℃）；TsHARP法在水體、裸地和建筑用地這些低植被覆蓋區(qū)表現(xiàn)出較差的降尺度結(jié)果，尤其對于裸地和建筑用地更為明顯（|MBE|＞3℃），新模型提高了低植被覆蓋區(qū)地物的降尺度精度；不同季節(jié)的降尺度結(jié)果表明，兩種模型都是夏、秋季的降尺度結(jié)果優(yōu)于春、冬季，新模型的降尺度結(jié)果四季均好于TsHARP法，其中春、冬季的降尺度精度提升效果要優(yōu)于夏、秋季。

關(guān)鍵詞：MODIS；降尺度；地表溫度；TsHARP算法；地表覆蓋

來源出版物：測繪學(xué)報,2017, 46(3):353-361

基于能量最優(yōu)的敏捷遙感衛(wèi)星在軌任務(wù)規(guī)劃

趙琳，王碩，郝勇，等

摘要：針對敏捷遙感衛(wèi)星對多個離散觀測點在軌自主任務(wù)規(guī)劃問題，在考慮姿態(tài)運(yùn)動方程耦合性的基礎(chǔ)上，將問題分解為空間資源調(diào)度問題和連續(xù)最優(yōu)控制問題，進(jìn)而提出了一種結(jié)合偽譜法和遺傳算法的混合求解算法。該算法針對基于行商問題（TSP）模型建立的空間資源調(diào)度問題模型，選用二維編碼結(jié)構(gòu)對觀測順序和相對觀測時間進(jìn)行實數(shù)編碼，并采用遺傳算法求解觀測序列和觀測時間；針對判斷觀測時間可行性時涉及的時間最優(yōu)控制問題、以及姿態(tài)轉(zhuǎn)移過程中涉及的最小能量消耗問題，將其歸結(jié)為連續(xù)最優(yōu)控制問題，并基于Gauss偽譜協(xié)態(tài)變量映射定理，采用Gauss偽譜法進(jìn)行求解。通過與基于單純遺傳算法的規(guī)劃算法進(jìn)行對比試驗，本文所提出的基于偽譜法和遺傳算法的混合求解策略針對目標(biāo)問題，在典型工況下姿態(tài)轉(zhuǎn)移過程中能量消耗降低60%。

關(guān)鍵詞：行商問題（TSP）；能量消耗；時間最優(yōu)；遺傳算法；Gauss偽譜法

來源出版物：航空學(xué)報,2017,38(6):202-220

聯(lián)系郵箱：郝勇，haoyong@hrbeu.edu.cn

以SRTM-DEM為控制的光學(xué)衛(wèi)星遙感立體影像正射糾正

張浩，張過，蔣永華，等

摘要：針對全球測圖缺少統(tǒng)一的控制基準(zhǔn)的問題，提出了利用 SRTM-DEM 作為控制基準(zhǔn)，對光學(xué)衛(wèi)星遙感影像進(jìn)行正射糾正的方法。首先，對光學(xué)衛(wèi)星影像構(gòu)建的立體影像對進(jìn)行自由網(wǎng)平差并制作 DEM；然后，以SRTM-DEM作為控制，將DEM作為單元模型，進(jìn)行獨立模型法DEM區(qū)域網(wǎng)平差，獲得單元模型的定向參數(shù)；最后，改正立體影像的成像幾何模型參數(shù)，進(jìn)行正射糾正。選取湖北咸寧和江西某地兩個測區(qū)的資源三號數(shù)據(jù)進(jìn)行試驗，試驗結(jié)果表明，資源三號正視全色影像的平面定向精度由12.93像素提高到6.85像素。

關(guān)鍵詞：全球測圖；立體像對；獨立模型法；DEM 區(qū)域網(wǎng)平差；影像定向精度

來源出版物：測繪學(xué)報,2016, 45(3):326G331-378

國產(chǎn)高分辨率遙感衛(wèi)星影像自動云檢測

譚凱，張永軍，童心，等

摘要：云檢測一直是衛(wèi)星影像處理的難題，特別是混有地物光譜特性的薄云長期成為影像產(chǎn)品生產(chǎn)的阻礙。本文所介紹的國產(chǎn)高分辨率遙感衛(wèi)星影像自動云檢測方法能夠有效克服這一難題。首先采用改進(jìn)的顏色轉(zhuǎn)換模型，將影像由RGB轉(zhuǎn)換至HIS顏色空間，利用影像強(qiáng)度信息與飽和度信息生成基底圖，并使用影像近紅外與色調(diào)信息對其進(jìn)行優(yōu)化，生成修正圖。然后利用直方圖均衡化與雙邊濾波結(jié)合帶限定條件的 Otsu閾值分割提取紋理信息，并對修正圖進(jìn)行誤差剔除生成云種子圖。最后以HIS顏色空間的強(qiáng)度信息為向?qū)ВY(jié)合云種子圖進(jìn)行云精確提取。與不同自動、人工交互式云檢測方法相比，總體精度提高了10%左右，并且能夠較好地提升云檢測效率。

關(guān)鍵詞：國產(chǎn)衛(wèi)星影像；云檢測；改進(jìn)HIS模型；雙邊濾波；Otsu閾值分割

來源出版物：測繪學(xué)報,2016, 45(5): 581-591

遙感衛(wèi)星影像K-SVD稀疏表示去噪

夏琴，邢帥，馬東洋，等

摘要：常規(guī)的去噪方法在去除遙感衛(wèi)星影像噪聲時，往往會造成影像模糊和空間分辨率下降。本文將稀疏表示理論應(yīng)用于遙感衛(wèi)星影像去噪，提出了一種改進(jìn)算法，能夠保留低頻信息不變，僅對影像的高頻信息進(jìn)行稀疏重建。算法核心是按照是否能夠從過完備字典中選擇較少原子進(jìn)行稀疏表示的原則來區(qū)分高頻信息中的有效信息和噪聲。通過3組實驗對改進(jìn)算法與傳統(tǒng)去噪方法進(jìn)行對比檢測，實驗結(jié)果表明，改進(jìn)算法在去除噪聲的同時，能較好地突出影像的邊緣和細(xì)節(jié)信息。

關(guān)鍵詞：遙感影像；稀疏表示；去噪；K-SVD；質(zhì)量評價

來源出版物：遙感學(xué)報,2016,20(3): 441-449

聯(lián)系郵箱：夏琴，xianduan007@163.com

衛(wèi)星遙感圖像的魯棒無損數(shù)據(jù)隱藏傳輸算法

朱厲洪，周詮

摘要：提出一種基于整數(shù)離散余弦變換（Int DCT）域的魯棒無損數(shù)據(jù)隱藏算法。先對載體圖像進(jìn)行預(yù)處理來構(gòu)建適合信息嵌入的載體，并將無損隱藏的思想引入到預(yù)處理中用以存儲可恢復(fù)原載體圖像的信息。為兼顧魯棒性和圖像質(zhì)量，算法通過修改載體圖像Int DCT域高頻系數(shù)的直方圖修改來完成秘密信息的嵌入；最后，與以往算法不同，為保證遙感圖像的質(zhì)量，給出了接收端在含密圖像未失真和失真情況下載體恢復(fù)的方法。實驗結(jié)果表明，本文所提出的算法能有效抵抗壓縮攻擊，并具有良好的圖像質(zhì)量和較大的容量。與以往算法相比，本文算法在性能方面具有明顯的優(yōu)勢。

關(guān)鍵詞：衛(wèi)星遙感圖像；無損數(shù)據(jù)；隱藏算法

來源出版物：宇航學(xué)報,2015,36(3):315-323

來源出版物：International Journal of Applied Earth Observation andgeoinformation,2017, 58:36-49

聯(lián)系郵箱：Sun, QS; qingsong.sun@umb.edu

Application of satellite solar-induced chlorophyll fluorescence to understanding large-scale variations in vegetation phenology and function over northern high latitude forestsJeong, SJ; Schimel, D; Frankenberg, C; et al.

Abstract:This study evaluates the large-scale seasonal phenology and physiology of vegetation over northern high latitude forests (40°–55°N) during spring and fall by using remote sensing of solar-induced chlorophyll fluorescence(SIF), normalized difference vegetation index (NDVI) and observation-based estimate ofgross primary productivity(GPP) from2009 to2011. Based ongPP phenology estimation ingPP, thegrowing season determined by SIF time-series is shorter in length than thegrowing season length determined solely using NDVI. This is mainly due to the extended period of high NDVI values, as compared to SIF, by about 46 days (±11 days), indicating a large-scale seasonal decoupling of physiological activity and changes ingreenness in the fall. In addition to phenological timing, mean seasonal NDVI and SIF have different responses to temperature changes throughout thegrowing season. We observed that both NDVI and SIF linearly increased with temperature increases throughout the spring. However, in the fall, although NDVI linearly responded to temperature increases, SIF andgPP did not linearly increase with temperature increases, implying a seasonal hysteresis of SIF andgPP in response to temperature changes across boreal ecosystems throughout theirgrowing season. Seasonal hysteresis of vegetation at large-scales is consistent with the known phenomena that light limits boreal forest ecosystem productivity in the fall.Our results suggest that continuing measurements from satellite remote sensing of both SIF and NDVI can help to understand the differences between, and information carried by, seasonal variations vegetation structure andgreenness and physiology at large-scales across the critical boreal regions.

關(guān)鍵詞：solar-induced chlorophyll fluorescence; SIF;NDVI;gPP; phenology; large-scale

來源出版物：Remote Sensing of Environment,2017,190:178-187

聯(lián)系郵箱：Jeong, SJ; waterbell77@gmail.com

ESA’s Soil Moisture and Ocean Salinity mission:From science to operational applications

Mecklenburg, S; Drusch, M; Kaleschke, L; et al.

Abstract:The Soil Moisture and Ocean Salinity (SMOS)mission, launched in November2009, is the European Space Agency’s (ESA) second Earth Explorer Opportunity mission. The scientific objectives of the SMOS mission directly respond to the need forglobal observations of soil moisture and ocean salinity, two key variables used in predictive hydrological, oceanographic and atmospheric models. SMOS observations also provide information on vegetation, in particular plant available water and water content in a canopy, drought index and flood risks, surface ocean winds in storms, freeze/thaw state and sea ice and its effect on ocean–atmosphere heat fluxes and dynamics affecting large-scale processes of the Earth's climate system.Significant progress has been made over the course of the now 6-year life time of the SMOS mission in improving the ESA provided level1 brightness temperature and level2 soil moisture and sea surface salinity data products. The main emphasis of this paper is to review the status of the mission and provide an overview and performance assessment of SMOS data products, in particular with a view towards operational applications, and using SMOS products in data assimilation. SMOS is in excellent technical condition with no limiting factors for operations beyond2017. The instrument performance fulfils the requirements. The radiofrequency interference (RFI) contamination originates from man-made emitters onground, operating in the protected L-band and adding signal to the natural radiation emitted by the Earth. RFI has been detected worldwide and has been significantly reduced in Europe and the Americas but remains a constraint in Asia and the Middle East. The mission’s scientific objectives have been reached over land and are approaching the mission objectives over ocean. This review paper aims to provide an introduction and synthesis to the papers published in this RSE special issue on SMOS.

關(guān)鍵詞：Soil Moisture and Ocean Salinity (SMOS)mission; sea surface salinity; soil moisture

來源出版物：Remote Sensing of Environment,2016,180:3-18

聯(lián)系郵箱：Mecklenburg, S; susanne.mecklenburg@esa.int

Ship detection in spaceborne optical image with SVD networks

Zou, ZX; Shi, ZW

Abstract:Automatic ship detection on spaceborne optical images is a challenging task, which has attracted wide attention due to its extensive potential applications in maritime security and traffic control. Although some optical image ship detection methods have been proposed in recent years, there are still three obstacles in this task:1)the inference of clouds and strong waves;2) difficulties in detecting both inshore and offshore ships; and3) high computational expenses. In this paper, we propose a novel ship detection method called SVD Networks (SVDNet),which is fast, robust, and structurally compact. SVDNet is designed based on the recent popular convolutional neural networks and the singular value decompensation algorithm.It provides a simple but efficient way to adaptively learn features from remote sensing images. We evaluate our method on some spaceborne optical images ofgaoFen-1 and Venezuelan Remote Sensing Satellites. The experimental results demonstrate that our method achieves high detection robustness and a desirable time performance in response to all of the above three problems.

關(guān)鍵詞：Convolutional neural networks (CNNs); optical spaceborne image; ship detection; singular

來源出版物：IEEE Transactions ongeoscience and Remote Sensing,2016, 54(10): 5832-5845

聯(lián)系郵箱：Shi, ZW; zhengxiazou@buaa.edu.cn

Sentinel-2’s potential for sub-pixel landscape feature detection

Radoux, J; Chome,g; Jacques, DC; et al.

Abstract:Land cover and land use maps derived from satellite remote sensing imagery are critical to support biodiversity and conservation, especially over large areas.With its10 m to20 m spatial resolution, Sentinel-2 is a promising sensor for the detection of a variety of landscape features of ecological relevance. However,many components of the ecological network are still smaller than the10 m pixel,i.e., they are sub-pixel targets that stretch the sensor’s resolution to its limit. This paper proposes a framework to empirically estimate theminimum object size for an accurate detection of a set of structuring landscape foreground/background pairs. The developed method combines a spectral separability analysis and an empirical point spread function estimation for Sentinel-2.The same approach was also applied to Landsat-8 and SPOT-5 (Take 5), which can be considered as similar in terms of spectral definition and spatial resolution,respectively. Results show that Sentinel-2 performs consistently on both aspects. A large number of indices have been tested along with the individual spectral bands and target discrimination was possible in all but one case.Overall, results for Sentinel-2 highlight the critical importance of agood compromise between the spatial and spectral resolution. For instance, the Sentinel-2 roads detection limit was of3 m and small water bodies are separable with a diameter larger than11 m. In addition, the analysis of spectral mixtures draws attention to the uneven sensitivity of a variety of spectral indices. The proposed framework could be implemented to assess the fitness for purpose of future sensors within a large range of applications.

關(guān)鍵詞：Sentinel-2; Landsat-8; SPOT-5; sub-pixel detection;spatial resolution; spectral resolution; point spread function

來源出版物：Remote Sensing,2016,8(6): UNSP 488

聯(lián)系郵箱：Radoux, J; julien.radoux@uclouvain.be

Using satellite remote sensing data to estimate the high-resolution distribution ofground-level PM2.5

Lin, CQ; Li, Y; Yuan, ZB; et al.

Abstract:Althoughground-level monitoring can provide accurate PM2.5measurements, it has limited spatial coverage and resolution. In contrast, satellite-based monitoring can provide aerosol optical depth (AOD) products with higher spatial resolution and continuous spatial coverage, but it cannot directly measureground-level PM2.5concentration.Observation-based and simulation-based approaches have been actively developed to retrieveground-level PM2.5concentrations from satellite AOD and sparseground-level observations. However, the effect of aerosol characteristics(e.g., aerosol composition and size distribution) on the AOD–PM2.5relationship is seldom considered in observation-based methods. Although these characteristics are considered in simulation-based methods, the results still suffer from model uncertainties. In this study, we propose an observation-based algorithm that considers the effect of the main aerosol characteristics. Their related effects on hygroscopicgrowth, particle mass extinction efficiency, and size distribution are estimated and incorporated into the AOD–PM2.5relationship. The method is applied to quantify the PM2.5distribution in China.good agreements between satellite-retrieved andground-observed PM2.5annual and monthly averages are identified, with significant spatial correlations of 0.90 and 0.76,respectively, at 565 stations in China. The results suggest that this approach can measure large scale PM distributions with verified results that are at least asgood as those from simulation-based estimations. The results also show the method's capacity to identify PM2.5spatial distribution with high-resolution at national, regional, and urban scales and to provide useful information for air pollution control strategies, health risk assessments, etc.

關(guān)鍵詞：satellite remote sensing; PM2.5; hygroscopicity;mass extinction efficiency; fine mode fraction

來源出版物：Remote Sensing of Environment,2015,156:117-128

聯(lián)系郵箱：Li, Y; yingli@ust.hk

A multi-temporal and multi-spectral method to estimate aerosol optical thickness over land,for the atmospheric correction of formosat-2,Landsat, venμs and Sentinel-2 images

Hagolle, O; Huc, M; Pascual, DV; et al.

Abstract:The correction of atmospheric effects is one of the preliminary steps required to make quantitative use of time series of high resolution images from optical remote sensing satellites. An accurate atmospheric correction requiresgood knowledge of the aerosol optical thickness(AOT) and of the aerosol type. As a first step, this study compares the performances of two kinds of AOT estimation methods applied to FormoSat-2 and LandSat time series of images: a multi-spectral method that assumes a constant relationship between surface reflectance measurements and a multi-temporal method that assumes that the surface reflectances are stable with time. In a second step, these methods are combined to obtain more accurate and robust estimates. The estimated AOTs are compared toin situmeasurements on several sites of the AERONET (Aerosol Robotic Network). The methods, based on either spectral or temporal criteria,provide accuracies better than 0.07 in most cases, but show degraded accuracies in some special cases, such as the absence of vegetation for the spectral method or a very quick variation of landscape for the temporal method.The combination of both methods in a new spectrotemporal method increases the robustness of the results in all cases.

關(guān)鍵詞：remote sensing; atmospheric correction; time series; aerosols; surface reflectance; LandSat; FormoSat-2;Sentinel-2; VENμS

來源出版物：Remote Sensing,2015,7(3):2668-2691

聯(lián)系郵箱：Hagolle, O; olivier.hagolle@cesbio.cnes.fr

Multi-mission cross-calibration of satellite altimeters: Constructing a long-term data record forglobal and regional sea level change studies

Bosch, W; Dettmering, D Schwatke, C

Abstract:Climate studies require long data records extending the lifetime of a single remote sensing satellite mission. Precise satellite altimetry exploringglobal and regional evolution of the sea level has now completed a two decade data record. A consistent long-term data record has to be constructed from a sequence of different, partly overlapping altimeter systems which have to be carefully cross-calibrated. This cross-calibration is realizedglobally by adjusting an extremely large set of single- and dualsatellite crossover differences performed between all contemporaneous altimeter systems. The total set of crossover differences creates a highly redundant network and enables a robust estimate of radial errors with a dense and rather complete sampling for all altimeter systems analyzed. An iterative variance component estimation is applied to obtain an objective relative weighting between altimeter systems with different performance. The final time series of radial errors is taken to estimate (for each of the altimeter systems) an empirical auto-covariance function. Moreover, the radial errors capture relative range biases and indicate systematic variations in thegeo-centering of altimeter satellite orbits. The procedure has the potential to estimate for all altimeter systems thegeographically correlated mean errors which is not at all visible in single-satellite crossover differences but maps directly to estimates of the mean sea surface.

關(guān)鍵詞：satellite altimetry; sea level; calibration; crossover analysis; range bias; radial errors;geographically correlated errors

來源出版物：Remote Sensing,2014, 6(3):2255-2281

聯(lián)系郵箱：Bosch, W; bosch@dgfi.badw.de

On-orbitgeometric calibration of ZY-3 three-line Array imagery with multistrip data sets

Yongjun, Z; Maoteng, Z; Jinxin, X; et al.

Abstract:ZY-3, which was launched on January9,2012,is the first stereo mapping satellite in China. The initial accuracy of directgeoreferencing with the onboard three-line camera (TLC) imagery is low. Sensorgeometric calibration with bundle block adjustment is used to improve thegeoreferencing accuracy. A new on-orbit sensor calibration method that can correct the misalignment angles between the spacecraft and the TLC and the misalignment of charge-coupled device is described. All of the calibration processes are performed using a multistrip data set. The control points are automatically matched from existing digital ortho map and digital elevation model. To fully evaluate the accuracy of different calibration methods, the calibrated parameters are used as input data to conductgeoreferencing and bundle adjustment with a total of19 strips of ZY-3 TLC data. A systematic error compensation model is introduced as the sensor model in bundle adjustment to compensate for the position and attitude errors. Numerous experiments demonstrate that the new calibration model can largely improve the external accuracy of directgeoreferencing from the kilometer level to better than20 m in both plane and height. A further bundle block adjustment with medium-accuracyground control points (GCPs), using these calibrated parameters, can achieve external accuracy of about 4 m in plane and3min height. Higher accuracy of about1.3min plane and1.7 m in height can be achieved by bundle adjustment using high-accuracygCPs.

關(guān)鍵詞：bundle block adjustment; directgeoreferencing;interior orientation parameters (IOPs); multistrip; on-orbitgeometric calibration; three-line camera (TLC); ZY-3

來源出版物：IEEE Transactions ongeoscience and Remote Sensing,2014, 52(1):224-234

聯(lián)系郵箱：Yongjun Zhang; zhangyj@whu.edu.cn

責(zé)任編輯：王微

Evaluation of theglobal MODIS30 arc-second spatially and temporally complete snow-free land surface albedo and reflectance anisotropy dataset

Sun, QS; Wang, ZS; Li, Z; et al.

Land surface albedo is an essential variable for surface energy and climate modeling as it describes the proportion of incident solar radiant flux that is reflected from the Earth’s surface. To capture the temporal variability and spatial heterogeneity of the land surface, satellite remote sensing must be used to monitor albedo accurately at aglobal scale. However, large datagaps caused by cloud or ephemeral snow have slowed the adoption of satellite albedo products by the climate modeling community. To address the needs of this community, we used a number of temporal and spatialgap-filling strategies to improve the spatial and temporal coverage of theglobal land surface MODIS BRDF, albedo and NBAR products. A rigorous evaluation of thegap-filled values showsgood agreement with original high quality data(RMSE = 0.027 for the NIR band albedo, 0.020 for the red band albedo). Thisglobal snow-free and cloud-free MODIS BRDF and albedo dataset (established from2001 to2015) offers unique opportunities to monitor and assess the impact of the changes on the Earth’s land surface.