986 research outputs found
X-band synthetic aperture radar methods
Spaceborne Synthetic Aperture Radars (SARs), operating at L-band and above, offer microwave observations of the Earth at very high spatial resolution in almost all-weather conditions. Nevertheless, precipitating clouds can significantly affect the signal backscattered from the ground surface in both amplitude and phase, especially at X band and beyond. This evidence has been assessed by numerous recent efforts analyzing data collected by COSMO-SkyMed (CSK) and TerraSAR-X (TSX) missions at X band. This sensitivity can be exploited to detect and quantify precipitations from SARs at the spatial resolution of a few hundred meters, a very appealing feature considering the current resolution of precipitation products from space. Forward models of SAR response in the presence of precipitation have been developed for analyzing SAR signature sensitivity and developing rainfall retrieval algorithms. Precipitation retrieval algorithms from SARs have also been proposed on a semi-empirical basis. This chapter will review experimental evidences, modelling approaches, retrieval methods and recent applications of X-band SAR data to rainfall estimation
Summary of the Active Microwave Workshop, chapter 1
An overview is given of the utility, feasibility, and advantages of active microwave sensors for a broad range of applications, including aerospace. In many instances, the material provides an in-depth examination of the applicability and/or the technology of microwave remote sensing, and considerable documentation is presented in support of these techniques. An assessment of the relative strengths and weaknesses of active microwave sensor data indicates that satisfactory data are obtainable for several significant applications
A New Orbiting Deployable System for Small Satellite Observations for Ecology and Earth Observation
In this paper, we present several study cases focused on marine, oceanographic, and
atmospheric environments, which would greatly benefit from the use of a deployable system for
small satellite observations. As opposed to the large standard ones, small satellites have become an
effective and affordable alternative access to space, owing to their lower costs, innovative design
and technology, and higher revisiting times, when launched in a constellation configuration. One
of the biggest challenges is created by the small satellite instrumentation working in the visible
(VIS), infrared (IR), and microwave (MW) spectral ranges, for which the resolution of the acquired
data depends on the physical dimension of the telescope and the antenna collecting the signal. In
this respect, a deployable payload, fitting the limited size and mass imposed by the small satellite
architecture, once unfolded in space, can reach performances similar to those of larger satellites.
In this study, we show how ecology and Earth Observations can benefit from data acquired by
small satellites, and how they can be further improved thanks to deployable payloads. We focus on
DORA—Deployable Optics for Remote sensing Applications—in the VIS to TIR spectral range, and
on a planned application in the MW spectral range, and we carry out a radiometric analysis to verify
its performances for Earth Observation studies
Earth resources: A continuing bibliography with indexes (issue 47)
This bibliography lists 524 reports, articles and other documents introduced into the NASA scientific and technical information system between July 1 and September 30, 1985. Emphasis is placed on the use of remote sensing and geophysical instrumentation in spacecraft and aircraft to survey and inventory natural resources and urban areas. Subject matter is grouped according to agriculture and forestry, environmental changes and cultural resources, geodesy and cartography, geology and mineral resources, hydrology and water management, data processing and distribution systems, instrumentation and sensors, and economical analysis
Microwave remote sensing from space for earth resource surveys
The concepts of radar remote sensing and microwave radiometry are discussed and their utility in earth resource sensing is examined. The direct relationship between the character of the remotely sensed data and the level of decision making for which the data are appropriate is considered. Applications of active and a passive microwave sensing covered include hydrology, land use, mapping, vegetation classification, environmental monitoring, coastal features and processes, geology, and ice and snow. Approved and proposed microwave sensors are described and the use of space shuttle as a development platform is evaluated
Earth Observing System. Volume 1, Part 2: Science and Mission Requirements. Working Group Report Appendix
Areas of global hydrologic cycles, global biogeochemical cycles geophysical processes are addressed including biological oceanography, inland aquatic resources, land biology, tropospheric chemistry, oceanic transport, polar glaciology, sea ice and atmospheric chemistry
Earth resources: A continuing bibliography with indexes (issue 55)
This bibliography lists 368 reports, articles and other documents introduced into the NASA scientific and technical information system between July 1 and September 30, 1987. Emphasis is placed on the use of remote sensing and geographical instrumentation in spacecraft and aircraft to survey and inventory natural resources and urban areas. Subject matter is grouped according to agriculture and forestry, environmental changes and cultural resources, geodesy and cartography, geology and mineral resources, hydrology and water management, data processing and distribution systems, instrumentation and sensors, and economic analysis
Earth resources: A continuing bibliography with indexes
This bibliography lists 579 reports, articles, and other documents introduced into the NASA scientific and technical information system. Emphasis is placed on the use of remote sensing and geophysical instrumentation in spacecraft and aircraft to survey and inventory natural resources and urban areas. Subject matter is grouped according to agriculture and forestry, environmental changes and cultural resources, geodesy and cartography, geology and mineral resources, hydrology and water management, data processing and distribution systems, instrumentation and sensors, and economical analysis
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