Microlab-1 experiment: Multipath effects in the lower troposphere
TLDR
In this article, the authors describe and validate a method of deciphering the ray structure of the measured electromagnetic field in regions of multipath propagation, which allows for the refinement of the vertical resolution beyond the Fresnel scale as well as for the improvement of the signal/noise ratio.Abstract:
Interpretation of the Doppler-shifted radio frequencies from the proof-of-concept GPS/MET radio occultation experiment is impeded by the effects of multipath propagation caused by strong variations of atmospheric refractivity. In this paper, we describe and validate a method of deciphering the ray structure of the measured electromagnetic field in regions of multipath propagation. The method is based on diffraction theory and the principles of the synthesized aperture, which allows for the refinement of the vertical resolution beyond the Fresnel scale as well as for the improvement of the signal/noise ratio. The validation of the method is based on artificial occultation data simulated using global fields from a NCEP analysis. An example of the application of the diffraction correction algorithm for the processing of real GPS/MET data is given. The comparison of the inversion results with and without diffraction correction indicates a very significant role of multipath propagation in the lower troposphere, which suggests that the diffraction correction can significantly improve the quality of the data processing.read more
Citations
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COSMIC System Description
Christian Rocken,Ying-Hwa Kuo,Willam S. Scheriner,Doug Hunt,Sergey Sokolovskiy,Chris McCormick +5 more
TL;DR: The constellation observing system for meteorology ionosphere and climate (COSMIC) is a satellite mission for the Earth sciences that will make use of recent developments in remote sensing, communications technology, and computing to solve some of the most important geo-scientific issues today as mentioned in this paper.
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Full Spectrum Inversion of radio occultation signals
TL;DR: In this article, the authors proposed a novel FSI technique for radio occultation sounding capable of disentangling multiple rays in multipath regions, which is based on the Doppler shift imposed by the atmosphere on a signal emitted from a GNSS satellite and received by a low orbiting satellite.
Journal ArticleDOI
Exploring earth's atmosphere with radio occultation: contributions to weather, climate and space weather
TL;DR: In this article, the authors summarized results from radio occultation (RO) observations and the applications of RO observations to atmospheric research and operational weather analysis and prediction, as well as the theoretical capabilities of RO to provide accurate and precise profiles of electron density in the ionosphere and refractivity, containing information on temperature and water vapor, in the stratosphere and troposphere.
Journal ArticleDOI
Applications of COSMIC to Meteorology and Climate
TL;DR: The constellation observing system for meteorology, ionosphere and climate (COSMIC) as mentioned in this paper is a follow-on project for weather and climate research, climate monitoring, space weather, and geodetic science.
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Tracking tropospheric radio occultation signals from low Earth orbit
TL;DR: In this paper, the results of simulations of open loop tracking of radio occultation signals that were generated with data from high-resolution tropical radiosondes were discussed and a fast algorithm for prediction of the Doppler based on the refractivity climatology and an algorithm for the detection of doppler mismodeling based on sliding window spectral analysis of the down-converted signal were developed and tested.
References
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Observing Earth's atmosphere with radio occultation measurements using the Global Positioning System
TL;DR: In this article, the authors present the first systematic, extensive error analysis of the spacecraft radio occultation technique using a combination of analytical and simulation methods to establish a baseline accuracy for retrieved profiles of refractivity, geopotential, and temperature.
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GPS Sounding of the Atmosphere from Low Earth Orbit: Preliminary Results
Randolph H. Ware,Christian Rocken,Fredrick Solheim,M. Exner,William Schreiner,Richard A. Anthes,D. Feng,Benjamin M. Herman,Michael E. Gorbunov,Sergey Sokolovskiy,K. Hardy,Ying-Hwa Kuo,Xiaolei Zou,Kevin E. Trenberth,Thomas K. Meehan,W. Melbourne,Steven Businger +16 more
TL;DR: In this article, a low Earth-orbiting satellite using the radio occultation technique was used to obtain temperature soundings from a small research satellite, MicroLab 1, carried a laptop-sized radio receiver.
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Analysis and validation of GPS/MET data in the neutral atmosphere
Christian Rocken,Richard A. Anthes,M. Exner,Douglas Hunt,Sergey Sokolovskiy,Randolph H. Ware,Michael E. Gorbunov,William Schreiner,D. Feng,Benjamin M. Herman,Ying-Hwa Kuo,Xiaolei Zou +11 more
TL;DR: The Global Positioning System/Meteorology ( GPS/MET) Program was established in 1993 by the University Corporation for Atmospheric Research (UCAR) to demonstrate active limb sounding of the Earth's atmosphere using the radio occultation technique.
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The atmosphere of Neptune : an analysis of radio occultation data acquired with Voyager 2
TL;DR: In this article, the vertical structure of Neptune's atmosphere was studied on the basis of recordings of the tracking signals received from Voyager 2 during its occultation by Neptune, and the measurements began at a planetographic latitude of 62 deg north and ended near 45 deg south, and cover an altitude interval of about 5000 km.