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281.
Michal Kačmařík Pavla Skřivánková 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
This paper discusses GPS (Global Position System) meteorology. The research presented is based on a comparison of values of precipitable water vapour PWV, based on GPS measurements using final and predicted ephemerides of satellite orbits. We analysed recent year’s improvement in predicting ephemerides. We compared the data outputs from a radiosonde using GPS receiver measurements directly from the meteorological station from which the radiosondes were launched. The results indicate a high quality of the predicted ephemerides. This finding makes predicted ephemerides highly usable for near real-time estimations of PWV. To use PWV in meteorological forecast applications, this high speed of PWV values supply is necessary. 相似文献
282.
Matthew A. Lazzara Alex Coletti Benjamin L. Diedrich 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
The ability to observe meteorological events in the polar regions of the Earth from satellite celebrated an anniversary, with the launch of TIROS-I in a pseudo-polar orbit on 1 April 1960. Yet, after 50 years, polar orbiting satellites are still the best view of the polar regions of the Earth. The luxuries of geostationary satellite orbit including rapid scan operations, feature tracking, and atmospheric motion vectors (or cloud drift winds), are enjoyed only by the middle and tropical latitudes or perhaps only cover the deep polar regions in the case of satellite derived winds from polar orbit. The prospect of a solar sailing satellite system in an Artificial Lagrange Orbit (ALO, also known as “pole sitters”) offers the opportunity for polar environmental remote sensing, communications, forecasting and space weather monitoring. While there are other orbital possibilities to achieve this goal, an ALO satellite system offers one of the best analogs to the geostationary satellite system for routine polar latitude observations. 相似文献
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强度关联遥感成像技术 总被引:1,自引:0,他引:1
过去十多年中,利用光场的量子(或经典)涨落及其关联获取目标图像信息的量子(强度)关联成像技术和基于自适应稀疏结构表象的信号处理技术的不断发展,为图像信息的获取提供了一条可突破传统光学成像技术图像分辨率和图像获取效率理论极限的全新技术途径。文章将概括地介绍这一研究方向,并简要讨论其在遥感领域中的应用前景和需要进一步研究的... 相似文献
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J.C. Pérez A. Cerdeña A. González M. Armas 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
In this work a methodology for inferring water cloud macro and microphysical properties from nighttime MODIS imagery is developed. This method is based on the inversion of a theoretical radiative transfer model that simulates the radiances detected in each of the sensor infrared bands. To accomplish this inversion, an operational technique based on Artificial Neural Networks (ANNs) is proposed, whose main characteristic is the ability to retrieve cloud properties much faster than conventional methods. Furthermore, a detailed study of input data is performed to avoid different sources of errors that appear in several MODIS infrared channels. Finally, results of applying the proposed method are compared with in-situ measurements carried out during the DYCOMS-II field experiment. 相似文献
287.
同步轨道遥感器热设计和热分析 总被引:2,自引:0,他引:2
为解决遥感器在同步轨道环境温度场分析中热传导与热辐射的综合处理问题,热传导模型温度计算采用控制容积方法建立有限差分方程;热辐射模型采用奥本海姆方法计算设备表面单元之间辐射换热;根据是否被遮挡,辐射换热中表面单元角系数的计算分别采用积分和数值方法。计算结果表明,采用上述方法进行温度场分析能够有效解决热传导模型与热辐射模型的耦合,求解精度较高,遥感器设备部件稳态分析温度分布和在轨瞬态分析温度曲线变化清楚,可作为进一步精密热控设计的依据。 相似文献
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Technology advances in sensor, digital technology and a standardised modular satellite bus are enabling a new generation of 80 kg micro-satellites with a better than 6.5 m GSD multi-spectral performance, to be specified, built and deployed with a dedicated launch within 12 months. The result of the standardised modular bus is lower cost, higher reliability and fast deployment. Operational remote sensing with a micro-satellite is thus within reach of individual organisations for dedicated missions. Sumbandilasat (pioneer in the Venda language) is a second generation satellite technology building on the expertise obtained in the Sunsat small satellite programme. The components used to build Sumbandilasat are the result of a technology development program of more than 3 years. Sumbandilasat is an operational technology demonstrator with more than 90% newly developed or improved subsystems and a compact refractive imager as a precursor to the MSMISat satellite with the same multi-spectral band set. The scalable, standardised modular satellite bus architecture enables satellites with a mass of 80–450 kg to be adapted to the specific mission requirements with minimum new engineering effort. 相似文献