Results 11 to 20 of about 601 (266)
Earth and Space Science, 2019 The Global Navigation Satellite System (GNSS) has proved to be a powerful tool for applications in meteorology. In this study, we propose a novel slant tropospheric delay (STD) model to obtain the vertical distribution of atmospheric refractivity based ...
Pengfei Xia +4 more
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Tropospheric profiles of wet refractivity and humidity from the combination of remote sensing data sets and measurements on the ground [PDF]
Atmospheric Measurement Techniques, 2013 We reconstruct atmospheric wet refractivity profiles for the western part of Switzerland with a least-squares collocation approach from data sets of (a) zenith path delays that are a byproduct of the GPS (global positioning system ...
F. Hurter, O. Maier
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Remote Sensing, 2021 The trapping layer refers to the atmospheric layer with vertical gradient of atmospheric refractivity less than −157 N-Units/km or vertical gradient of atmospheric modified refractivity 0 M-unit/km, which has a significant impact on radar and radio ...
Yong Zhou +11 more
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Refraction and atmospheric photochemistry [PDF]
Journal of Geophysical Research: Atmospheres, 1997 A new model for calculating the effects of refraction is introduced. This model was invented independently of the one described by DeMajistre et al.[1995], but it is shown that the two models are analytically equivalent. However, the numerical implementation of the model introduced here is vastly more economical and efficient than that of the model by ...
M. Balluch, D. J. Lary
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Retrieving tropospheric refractivity structure using interferometry of aircraft radio transmissions [PDF]
Atmospheric Measurement TechniquesDetailed measurements of atmospheric humidity in the lower atmosphere are currently difficult and expensive to obtain. For this reason, there is interest in the development of low-cost, high-volume opportunistic technologies to acquire measurements of ...
O. Lewis +5 more
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Scientific African, 2021 Radio refractivity, which is the bending of a radio signal as it propagates through media, is very important in works involving terrestrial atmospheric electromagnetic propagation such as point-to-point microwave communication, terrestrial radio and ...
O.J. Abimbola +5 more
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Study of Seasonal Surface Refractivity over NorthCentral Nigeria [PDF]
Physics Access, 2021 Tropospheric radio wave signals experience loss due to multipath effect, scattering and other forms of attenuation through the atmospheric medium, primarily due to variations in weather conditions with time.
Muhammad B Ladan +8 more
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An atmospheric refractivity inversion method based on deep learning
Results in Physics, 2019 An atmospheric refractivity inversion method based on deep learning is introduced. Atmospheric duct is an anomalous phenomenon of electromagnetic waves in the atmosphere that affects the use of radio equipment, obtaining real-time atmospheric duct ...
Wenlong Tang +4 more
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Improving the Wet Refractivity Estimation Using the Extremely Learning Machine (ELM) Technique
Atmosphere, 2023 Constructing accurate models that provide information about water vapor content in the troposphere improves the reliability of numerical weather forecasts and the position accuracy of low-cost Global Navigation Satellite System (GNSS) receivers. However,
Ehsan Forootan +3 more
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Frontiers in Earth Science, 2020 We performed some refinements to the Boundary Profile eValuation (BPV) method, developed by Vespe and collaborators (Vespe et al., 2004; Vespe and Persia, 2006; Vespe, 2016), for the retrieval of vertical atmospheric humidity profiles from Radio ...
Andrea Andrisaniand +2 more
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