共查询到19条相似文献，搜索用时 453 毫秒
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风廓线雷达用于探测其上空风向、风速等气象要素随高度的变化情况,在自动化程度和探测时空分辨率等方面优势明显,已逐渐广泛应用于机场气象探测.本文以民用机场拟建风廓线雷达遮蔽角的测绘方法和实践为例,介绍如何测定并计算拟建风廓线雷达四周范围内障碍物的遮蔽角,并根据测算遮蔽角值判断障碍物是否对风廓线雷达信号发射造成影响,为申请风... 相似文献
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机场导航台遮蔽角的计算能够为飞机提供飞行保障,保障雷达在各方向上的安全扫描.常规的计算方法都是基于格网DEM采用通视分析(LOS)的方法进行计算,无法使用机场建设前期未经格网化的地形图数据.文中针对机场设计阶段的需求,提出一种基于数字地形图高程线的改进LOS分段斜率比较法(SK-LOS),通过对数字地形图上的高程线数据进行抽稀和索引,筛选符合求交条件的高程线,实现各方向遮蔽角的快速计算,并结合工程实践实现计算的流程化处理.通过在云南省某通用机场导航台建设中的实践表明,该方法较传统的LOS方法效率提高100％ 以上,计算结果准确可靠,精度满足机场导航台的设计要求. 相似文献
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李乾乾郭黎刘贺王彩璇张婉晨白翔天 《测绘与空间地理信息》2023,(5):55-58
针对雷达遮蔽角计算效率不高、雷达探测信息可视化不及时等问题,本文提出一种快速计算雷达遮蔽角的方法,考虑地球曲率对遮蔽角计算的影响,绘出雷达不同高度层的可视域。并以全球影像数据和全球数字高程模型等地理空间数据为基础,开发基于WebGL协议和B/S架构的遮蔽角分析系统,实现雷达可视域及遮蔽角信息的实时可视化,在虚拟的三维环境中直观、动态、实时地展示雷达可探测区域,为雷达阵地部署提供决策依据。 相似文献
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天气雷达站址选择的有效地理视距分析 总被引：1，自引：0，他引：1
本文在详细介绍了雷达遮蔽角图和雷达等射束高度图的制作原理和方法的基础上,分析了天气雷达的有效地理视距,开发了天气雷达有效地理视距分析系统。该系统能自动绘制雷达遮蔽角图和等射束高度图,并能对天气雷达候选站址的有效地理视距进行分析,这能为寻求天气雷达最佳候选站址带来方便。 相似文献
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针对各型天气雷达大量建设部署,却仍缺少准确直观判断单站雷达净空环境和组网雷达探测盲区分析软件的问题,设计开发了一种基于数字高程模型的天气雷达选址软件。软件使用雷达站点、数字高程模型、遮挡障碍物等地理信息数据,处理绘制单站雷达遮蔽角图、等射束高度图及组网雷达等射束高度拼图。通过Python语言编程,结合数字高程模型计算雷达站点的遮挡仰角、遮挡方位与等射束高度最大探测距离,分析所选站址净空条件。利用湖北省天气雷达网作为实际应用背景,与视程客观分析软件展开结果比对。实验结果表明：天气雷达选址软件应用数字高程模型等地理信息数据可算出拟选站址四周的遮挡情况,显示天气雷达的实际探测范围,为雷达建设组网提供技术支撑。 相似文献
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本文论述了数字地图自动高程修正，雷达遮蔽角自动计算的基本原理，同时，给出了雷达坐标系统转换的基本公式，并在此基础上，验证了一个雷达坐标系统转换的简易公式。 相似文献
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雷达网发现概率一般采用库普曼概率模型的解析式来计算,这种方法对参与组网的雷达空间位置因素考虑不够。引入空间叠置分析方法改进了雷达网发现概率计算模型,并进行了仿真验证。 相似文献
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在综合运用RS、GIS和构建三维地理信息的平台基础上,利用多分辨率卫星遥感数据及地形数据等海量数据生成三维地形数据,并实现了快速浏览。整合引接民航各专业数据,将三维空间数据,飞行航路航线、管制雷达、机场、气象、通信导航、空域等数据,管理信息,业务流程等多业务平台、多管理系统结合起来,设计、构建了新疆民航空中运行管理系统,为民航空中交通提供更加方便快捷、更加科学化现代化的管理手段。 相似文献
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Bing Lin Yongxiang Hu 《Geoscience and Remote Sensing Letters, IEEE》2005,2(3):324-328
An active microwave method is investigated for measuring surface air pressure by using radar reflections at frequencies around 53-55 GHz O/sub 2/ bands. The numerical simulation results for homogeneous backgrounds show that with an airborne radar working at these O/sub 2/ absorption bands, the rms errors of the radar surface pressure estimations with 15-dB signal-to-noise ratio can be as low as 4-7 mb. A radar system that covers these wavelengths will have great potentials for weather observations and other meteorological applications. 相似文献
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《The Cartographic journal》2013,50(4):291-296
AbstractManual shading, traditionally produced manually by specifically trained cartographers, is still considered superior to automatic methods, particularly for mountainous landscapes. However, manual shading is time-consuming and its results depend on the cartographer and as such difficult to replicate consistently. For this reason there is a need to create an automatic method to standardize its results. A crucial aspect of manual shading is the continuous change of light direction (azimuth) and angle (zenith) in order to better highlight discrete landforms. Automatic hillshading algorithms, widely available in many geographic information systems (GIS) applications, do not provide this feature. This may cause the resulting shaded relief to appear flat in some areas, particularly in areas where the light source is parallel to the mountain ridge. In this work we present a GIS tool to enhance the visual quality of hillshading. We developed a technique based on clustering aspect to provide a seamless change of lighting throughout the scene. We also provide tools to change the light zenith according to either elevation or slope. This way the cartographer has more room for customizing the shaded relief representation. Moreover, the method is completely automatic and this guarantees consistent and reproducible results. This method has been embedded into an ArcGIS toolbox. 相似文献
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Gang Hong Heygster G. Jungang Miao Kunzi K. 《Geoscience and Remote Sensing Letters, IEEE》2005,2(1):40-44
The effects of cloud structures on microwave radiances at frequencies from 89-190 GHz are investigated by simulations using the Goddard cumulus ensemble model data as input for a radiative transfer model. It was found that the brightness temperatures at these frequencies have different sensitivities to clouds with a tilted structure. The different sensitivities to altitude and amount of hydrometeors allow the estimation of the canting angle and tilt direction of tilted clouds using brightness temperatures at the water vapor channels at 183.3 /spl plusmn/ 1 and 183.3 /spl plusmn/ 7 GHz. The estimated canting angle and tilt direction are in agreement with the model situation. This method provides a potential to estimate tilted convective structures from microwave radiometric observations at 183.3 /spl plusmn/ 1 and 183.3 /spl plusmn/ 7 GHz. It is applied to a tilted storm observed from the National Aeronautics and Space Administration's ER-2 aircraft flying at about 20 km on August 26, 1998 during the third Convection and Moisture Experiment using the observed downlooking brightness temperatures at the water vapor channels of a Millimeter-wave Imaging Radiometer. The estimated results are in good agreement with the realistic storm situation obtained from the simultaneous observations of the ER-2 Doppler radar. This method also provides information about the vertical displacement of cloud structure and thereby to estimate the accurate location of surface rainfall. This is important when validating precipitation retrieval based on observations of the ice scattering above surface rainfall against surface rain observations using the microwave frequencies sensitive to high altitudes. 相似文献