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Retrieving Refractivity using Interferometry of Refracted Aircraft Radio Broadcasts
Water vapour is the key tropospheric constituent driving meteorological processes in the atmosphere of Earth.  However, its extreme spatial and temporal variability in the lower atmosphere presents an enormous challenge for existing observing systems.Ollie Lewis +2 more
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Ionospheric refraction effects on radio interferometer phase
Journal of Astrophysics and Astronomy, 1987The refraction of radio waves as they traverse through the terrestrial ionosphere and troposphere introduces a differential phase path which results for a radio interferometer in variations of the visibility phase. Though refraction due to troposphere is significant for synthesis radio telescopes operating at 1.0 GHz and above, ionospheric refraction ...
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Software radio measurements of Earth atmosphere's refractive indices
Proceedings of 2011 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing, 2011An atmosphere imaging device is being constructed to investigate its ability to measure the Earth atmosphere's three-dimensional (3D) refractive indices for use to help monitor climate change. With the recent advancements of Software Defined Radio (SDR) and Global Positioning Systems (GPS) with clocks having timers of 10 second precision, a method to ...
R. A. Herring +3 more
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Refraction of Short Radio Waves in the Upper Atmosphere
Transactions of the American Institute of Electrical Engineers, 1926The paper shows that the striking phenomena of short-wave radio transmission (i. e., below 60 meters) can be quantitatively accounted for on a simnple electron refraction theory in which the effect of the earth's magnetic field and electron collisions may be neglected as a first approximation. The distribution and number of electrons per unit volume in
William G. Baker, Chester W. Rice
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Remote sensing of radio refractivity by lidar
Tenth International Conference on Antennas and Propagation (ICAP), 1997Deterministic modelling of tropospheric radio propagation and exploitation of variations of microwave radar propagation require high quality, high resolution refractivity profiles in the first 1-2 km above the Earth's surface. Currently, routine measurements of refractivity are based on radiosonde measurements (via in-situ measurement of temperature ...
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Applications of the molecular refractivity in radio meteorology
Journal of Geophysical Research, 1959Consideration of the molecular refractivity has led to a value of the radio refractive index referred to zero altitude or sea level that effectively removes the systematic altitude dependence of air density. The advantages of this new parameter are illustrated by two applications.
B. R. Bean, R. M. Gallet
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Ionospheric refraction of 81.5 Mc/s radio waves from radio stars
Journal of Atmospheric and Terrestrial Physics, 1952Abstract Ionospheric refraction of radio waves from radio stars may cause variations in the apparent right ascensions of the stars because of horizontal gradients in the total ionisation of the ionosphere. These gradients occur during the normal diurnal changes of the F -region, and observations of their magnitude allow an estimate to be made of the
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Variation of radio refraction in the lower atmosphere
IEEE Transactions on Antennas and Propagation, 1968Measurements of the variation of the incident angle were made on several line-of-sight paths, together with the simultaneous observation of the refractive index gradient of the atmosphere. Statistics of incident angle variation and M -gradient and their relations were analyzed.
F. Ikegami +3 more
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A Tethered Psychrosonde for Radio Refractivity Profile Measurements
IETE Journal of Research, 1982The Indian sub-continent is subject to a varied and complex pattern of anomalous propagation conditions. These have a direct and significant influence on the performance of radar and microwave equipment.This paper describes the instruments and a recoverable Kytoon facility, developed for the first time in India to measure the gradient of temperature ...
S.P. Venkiteshwaran +3 more
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On the theory of refractive radio-wave scattering
Radiophysics and Quantum Electronics, 1995We consider in detail the frequency correlation of radio-wave fluctuations in one or several thick layers with strong large-scale inhomogeneities of turbulent origin. General expressions are obtained for the space-frequency fluctuation correlation of the radio-waves received.
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