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1.
ERS散射计全球海面风场数据处理与ElNino海面风场异常观测   总被引:1,自引:0,他引:1  
王超 《遥感学报》1999,3(4):300-304,324
星载散射测量技术是获取全球海面风场的有效手段。该文研究了欧洲遥感卫星(ERS) 散射计全球海面风场数据的处理分析技术。对1997 年3 月、6 月和12 月的全球海面风场数据进行平均处理,并同时与1996 年6 月和1995 年10 月的观测数据进行对比,利用遥感技术发现了赤道太平洋西部的风场异常,从遥感资料上分析了1997 年El Nino 现象的海面风场( 风速与风向) 异常变化特征。研究结果显示了星载微波散射计在全球变化监测中的重要作用。  相似文献   

2.
GNSS海面反射信号的建模对全球导航卫星系统反射测量(Global Navigation Satellite System-Reflectometry,GNSS-R)遥感应用具有重要意义.针对海面GNSS反射信号建模问题,本文采用Z-V模型研究了GNSS反射信号的时延一维相关功率和时延-多普勒二维相关功率特征,分析了不同风速下一维相关功率的变化情况,讨论了时延间隔和多普勒间隔对时延-多普勒图(delayDoppler map,DDM)的影响.数值结果表明:海面GNSS反射信号的相关功率对海面风速具有敏感性,在DDM波形仿真中,应选择合适的时延与多普勒间隔参数.该模型可模拟不同海况下海面GNSS反射信号的相关功率,为GNSS-R反射信号模拟及海洋遥感应用提供理论模型支撑.  相似文献   

3.
卫星高度计反演海面风速——模式函数与应用实例   总被引:6,自引:1,他引:6  
陈戈 《遥感学报》1999,3(4):305-311,325
对迄今为止国际上公开发表的14 种卫星高度计反演海面风速的模式函数进行了系统的分析和比较。在此基础上提出了一种“折中”模式函数,用于TOPEX 资料海面风速反演效果良好。文中对高度计获取的全球海面风速分布特征进行了分析,最后探讨了改善海面风速模式函数反演精度的途径。  相似文献   

4.
GNSS-R海洋遥感方法研究   总被引:1,自引:2,他引:1  
对利用全球导航定位系统(GNSS)的海洋反射信号(GNSS-R)反演海面要素的方法进行了详细讨论。在归纳国外研究成果的基础上,系统地整理和阐述了利用GNSS-R反演海洋要素的理论模型、方法以及反演流程,特别对GNSS-R的信号特征以及功率波形进行了详细讨论和公式推导。  相似文献   

5.
海洋雷达后向散射回波主要来自短重力波的Bragg 散射,这种散射与海面风场信息、边界层涡旋等密切相关。因此,可以从雷达散射截面反演风场信息。对1994 年4 月航天飞机成像雷达(SIRC/XSAR)获取的南中国海合成孔径雷达(SAR) 图像进行了分析研究。利用SIRC 数据,从SAR 图像谱提取了风向;根据CMOD4 模型,从C波段雷达后向散射系数反演风速;利用双尺度散射模型对反演的风速进行了对比分析。结果表明,从SIRC雷达数据可以反演海面风矢量,星载SAR是提取海面风场信息的有效技术手段之一。  相似文献   

6.
卫星测高开辟了地球科学研究的新纪元。平均海面高(MSSH)和海洋重力异常是卫星测高在大地测量和地球物理应用领域的重要成果。平均海面高对于建立全球潮汐模型、海平面变化研究以及海洋测深等方面有重要意义。关于海洋重力异常的应用,Sandweel与Smith(1997)已进行了说明。根据卫星测高数据计算垂线偏差(DOV)是恢复重力异常的一个新途径。对利用改进的卫星测高数据进一步提高全球平均海面高和重力异  相似文献   

7.
海面高度作为最重要的海洋物理参数之一,在预防海啸、风暴潮中起到重要作用,是海洋科学,遥感测绘领域的重要研究内容之一。粗糙度作为影响海面测高精度的重要因素之一,主要是由风速变化引起,本文为了探究风速引起的粗糙度变化对海面测高精度的影响,分别进行了湖面实验与海面实验。通过对风速与反射信号相位差RMS关系的研究,定性分析了粗糙度对测高精度的影响,结果表明,在反射信号相位差RMS增加0.005(单位rad)时,测高的误差RMS增加了近一倍。   相似文献   

8.
GNSS-R航空遥感海面风场仿真技术   总被引:2,自引:1,他引:1  
周晓中  邵连军 《遥感学报》2012,16(1):143-153
研究了机载GNSS-R遥感海面风场的仿真原理和技术,以KA-GO相关功率模型为基础,分析海浪谱,海面坡度和风速风向的关系,并针对不同风速、风向、接收机高度和飞行速度海面散射信号相关功率开展了数值仿真分析研究,并建立了仿真软件。仿真研究结果表明,以上因素对海面反射信号的相关功率波形的峰值和后沿斜率均有影响。本文的仿真结论为GNSS-R海面风场反演打下了理论基础,建立的仿真软件为GNSS-R海面风场反演提供研究平台。  相似文献   

9.
王超  潘广东 《遥感学报》2000,4(1):51-54
海洋雷达后向散射回波主要来自短重力波的Bragg散射,这种散射与海面风场信息、边界层涡旋等密切相关。因此,可以从雷达散射截面反演风场信息。对1994年4月航天飞机成像雷达(SIR-C/X-SAR)获取的南中国海合成孔径雷达(SAR)图像进行了分析研究。利用SIR-C数据,从SAR图像谱提取了风向;根据CMOD4模型,从C波段雷达后向散射系数反演风速;利用双尺度散射模型对反演的风速进行了对比分析。结  相似文献   

10.
在研究西太平洋海域海面动力地形时发现,菲律宾西部苏禄海盆地海面动力地形不但大大高于周围海域,而且是全球的最高点。从动力计算的角度分析,这是由于该海域存在着一个巨大的高温水体。本文从地热学、海底科学、海洋物理学和海底构造学角度探讨了温度分布异常的机制,为该海域的海面动力异常及全球三大洋动力高度的差异作出了初步解释。  相似文献   

11.
Multi-channel Scanning Microwave Radiometer (MSMR) onboard 1RS P4 (Oceansat I) measured Brightness Temperature data of the different bands are found sensitive to the surface and the overlying atmosphere to different degrees. A judicious combination of multi-channel data can provide such oceanic/atmospheric parameters as surface wind speed, sea surface temperature, water vapour in the marine atmosphere, etc. This paper highlights results obtained in relation to surface wind speed. Co-location and concurrence of several ocean data buoys in the Arabian Sea with MSMR observations allowed empirical construction of D-matrix coefficients for surface wind speed. With both MSMR and the Arabian Sea buoys functioning for the period of one and a half year (June, 1999 to December, 2000) without interruptions provided a large database. All channels are found to exhibit moderate sensitivity to surface wind speed. MSMR data in the immediate vicinity (within 150 km) of the buoy locations and within a time window of one hour were used. A multi-channel linear equation for surface wind speed was subsequently derived. The equation was subjected to tests with independent data set for the period January - June 2001 over the Arabian Sea and found to be moderately accurate. The empirical equation is expected to be useful for regional applications over the Arabian Sea and over regions closer to west coasts, which might have been flagged out in the operational geophysical data stream. An interesting subset of data revealed the wind signatures of the May 2001 cyclone in the Arabian Sea.  相似文献   

12.
地理信息系统集成平台框架结构研究   总被引:51,自引:3,他引:48  
张健挺  万庆 《遥感学报》1999,3(1):77-83
提出了基于客户/服务器结构的地理信息系统集成平台总体结构,探讨了基于元数据的地理信息系统数据集成平台以建立物理上分布而逻辑上集中的分布式地理信息系统数据库,提出了应用符合3NF范式的关系数据库进行模型管理的模式,在此基础上探讨了地理信息系统可视化建模工具。  相似文献   

13.
以广州市为例,以高分辨率的遥感影像及电子地图为主要数据源,以遥感图像处理软件及地理信息系统为主要分析工具,探讨了通过RS和GIS来提取绿地信息的方法,其中重点阐述了遥感影像处理、绿地信息提取及建库过程。  相似文献   

14.
快速反演(FDI)算法是一种典型的星载全球卫星导航反射技术(GNSS-R)海面风速反演方法,具有计算复杂度低、快速实时反演的特点,但是FDI算法中的反演观测量提取精度不高,导致风速反演精度低. 针对于此,提出基于观测量校正的改进FDI算法,用于实现海面风速的快速高精度反演. 该方法首先利用辅助测量信息对观测量进行校正以降低干扰因素的影响,然后基于统计分析方法对ASCAT卫星风速数据进行海面风速值提取,最后建立了海面风速与校正观测量的地球物理模型函数(GMF)关系式,实现对海面风速的反演. 与传统FDI算法相比,该方法的反演偏差值更小,均方根误差(RMSE)降低了29%.   相似文献   

15.
针对水库水源保护区土地巡查及移交过程中复杂的实际情况和管理难度,本文以深圳市西丽水库为例,引入3S技术研究了水库水源保护区土地巡查信息管理系统建立的过程。首先在系统分析基础上设计了集成3S技术的体系结构,集成全球卫星导航系统(GNSS)实现了厘米级实时定位和毫米级变形监测,为水库土地巡查提供精确的定位信息;集成高分遥感技术和无人机遥感技术(RS),实现水库土地巡查数据的快速和大范围更新;利用GIS的空间分析和空间数据管理等功能,实现水库各种数据统一存储和管理。在此基础上,对水库土地巡查信息管理系统功能模块进行设计与开发,结合移动端APP软件和客户端GIS系统的开发,实现了土地巡查路线和数据的更新显示与即时查询分析。该系统已在西丽水库进行了实地验证并投入使用,为水库管理部门提供了一个可视化的决策辅助管理平台。  相似文献   

16.
RS与GIS一体化数据结构的研究   总被引:1,自引:0,他引:1  
详细阐述了RS与GIS一体化的概念 ,通过对RS与GIS一体化方面的研究与分析 ,进一步明确RS与GIS一体化对空间数据存储结构的要求 ,着重探讨了几种典型的用于RS与GIS一体化的数据结构 ,针对现有数据结构存在的问题与不足 ,提出了一种具有普遍适用价值的基于语义网络的空间数据存储结构 ,并给出一个应用实例  相似文献   

17.
In this study, remote sensing (RS) with computer-based geographic information systems (GIS) techniques are used as a tool for monitoring the water basin area and water quality in Istanbul's relatively less polluted and comparatively less destroyed catchment of the metropolis drinking water dam reservoir named Terkos. It is necessary to work with recent data to be able to identify the effects of urbanization on the water quality of the Terkos dam catchment area that supplies drinking water to the metropolis. RS is an important tool to monitor water quality and urban terrain. For this aim, a project has been initiated at the Technical University Remote Sensing Laboratory, under the Istanbul Water and Sewerage Administration (ISKI) sponsorship in Istanbul. The project uses SPOT-PAN, XS and IRS-1C/D PAN and satellite data of 1993 and 2000 for urban analysis and Landsat-TM and LISS-III satellite data of 1992 and 2000 for water quality. For calibration and validation, ground truth samples are collected from the experimental area. The RS data was converted into the UTM coordinate system and image enhancement and classification techniques are used. Raster data is converted to vector data to assess the study area for analyzing in GIS for the purpose of planning and decision-making on protected water basin zones. As a result of monitoring land use and water quality changes, recommendations are made for planning and management of the protected environment of the Terkos catchment protected area. Measuring land use change is a very important issue for controlling the future development of the basin, GIS techniques are performed and results are illustrated in established models on the four protected zones of Terkos water basin.  相似文献   

18.
1 TheconceptoftheintegrationofRSwithGISTheintegrationofremotesensing (RS)withgeo graphicalinformationsystem (GIS)isahotspotingeographicalinformationscience .TheconceptoftheintegrationofRSwithGIS ,intheviewofProf.LiDeren ,isthatRSisthewaytoobtaintheinforma ti…  相似文献   

19.
This letter uses a large ocean satellite data set to document relationships between Ku-band radar backscatter (sigmao) of the sea surface, near-surface wind speed (U), and ocean wave height (SWH). The observations come from satellite crossovers of the Tropical Rainfall Mapping Mission (TRMM) Precipitation Radar (PR) and two satellite altimeters, namely: 1) Jason-1 and 2) ENVISAT. At these nodes, we obtain TRMM clear-air normalized radar cross-section data along with coincident altimeter-derived significant wave height. Wind speed estimates come from the European Centre for Medium-Range Weather Forecast. TRMM PR is the first satellite to measure low incidence Ku-band ocean backscatter at a continuum of incidence angles from 0deg to 18deg. This letter utilizes these global ocean data to assess hypotheses developed in past theoretical and field studies.  相似文献   

20.
The integration of remote sensing (RS) with geographical information system (GIS) is a hotspot in geographical information science. A good database structure is important to the integration of RS with GIS, which should be beneficial to the complete integration of RS with GIS, able to deal with the disagreement between the resolution of remote sensing images and the precision of GIS data, and also helpful to the knowledge discovery and exploitation. In this paper, the database structure storing the spatial data based on semantic network is presented. This database structure has several advantages. Firstly, the spatial data is stored as raster data with space index, so the image processing can be done directly on the GIS data that is stored hierarchically according to the distinguishing precision. Secondly, the simple objects are aggregated into complex ones. Thirdly, because we use the indexing tree to depict the relationship of aggregation and the indexing pictures expressed by 2-D strings to describe the topology structure of the objects, the concepts of surrounding and region are expressed clearly and the semantic content of the landscape can be illustrated well. All the factors that affect the recognition of the objects are depicted in the factor space, which provides a uniform mathematical frame for the fusion of the semantic and non-semantic information. Lastly, the object node, knowledge node and the indexing node are integrated into one node. This feature enhances the ability of system in knowledge expressing, intelligent inference and association. The application shows that this database structure can benefit the interpretation of remote sensing image with the information of GIS.  相似文献   

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