A modified artificial neural network based prediction technique for tropospheric radio refractivity. [PDF]
PLoS ONE, 2018 Radio refractivity plays a significant role in the development and design of radio systems for attaining the best level of performance. Refractivity in the troposphere is one of the features affecting electromagnetic waves, and hence the communication ...
Shumaila Javeed +4 more
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Comparative study on Radio Refractivity Gradient in the troposphere using Chaotic Quantifiers [PDF]
Heliyon, 2019 Complexity and nonlinear trend in the internal activities of the troposphere has been a great factor affecting the transmission and receiving of good quality of signals globally.
J.S. Ojo, A.O. Adelakun, O.V. Edward
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Global analysis of atmospheric refractivity profiles from COSMIC GPS radio occultation soundings [PDF]
Geodetski Vestnik, 2020 Atmospheric refractivity is a function of temperature, pressure and water vapor. The refractivity retrieved from the Global Navigation Satellite Systems (GNSS) radio occultation soundings has fine vertical resolution and high accuracy, so it can be used ...
Shaoqi Gong +4 more
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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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Ionospheric Refraction in Radio Astronomy. I. Theory [PDF]
Australian Journal of Physics, 1960 Expressions are derived for the apparent displacements of cosmic radio sources at transit resulting from ionospheric refraction. The derivation takes account of horizontal electron density gradients whose effects often outweigh the refraction expected from a spherically symmetrical ionosphere. .
M. M. Komesaroff
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Variation of Radio Refractivity with Height above Ground
Elektronika ir Elektrotechnika, 2011 In Vilnius, the daily and the seasonal variations of the radio refractivity values have been computed at the Earth surface in the years 2005-2010 and at the heights up to 1.2 km in November 2010. The International Telecommunications Union - Radiocommunications Sector (ITU-R) model was used for calculation of the radio refractive index according to the ...
E. Valma +4 more
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Meteorologische Zeitschrift, 2012 Radio-wave refractivity conditions in the atmosphere are determined by the vertical gradient of the refractive index, which can be computed from regular aerological balloon probe measurements. This study is focused on the refractivity conditions over the
Mladen Viher, Maja Teli Sman Prtenjak
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Correcting negatively biased refractivity below ducts in GNSS radio occultation: an optimal estimation approach towards improving planetary boundary layer (PBL) characterization [PDF]
Atmospheric Measurement Techniques, 2017 Global Navigation Satellite System (GNSS) radio occultation (RO) measurements are promising in sensing the vertical structure of the Earth's planetary boundary layer (PBL).
K.-N. Wang +3 more
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The impact of differences in retrieval algorithms between processing centers on GNSS radio occultation refractivity retrievals in the planetary boundary layer [PDF]
Atmospheric Measurement TechniquesGlobal Navigation Satellite System radio occultation (GNSS RO) performance in the planetary boundary layer is strongly dependent on retrieval algorithms. In this work, we characterize differences in refractivity retrievals in the planetary boundary layer
S. Vannah +6 more
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Estimation of refractivity uncertainties and vertical error correlations in collocated radio occultations, radiosondes, and model forecasts [PDF]
Atmospheric Measurement Techniques, 2022 Random uncertainties and vertical error correlations are estimated for three independent data sets. The three collocated data sets are (1) refractivity profiles of radio occultation measurements retrieved from the Metop-A and B and COSMIC-1 missions, (2)
J. K. Nielsen +3 more
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