Results 261 to 270 of about 789,573 (302)
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A Nomogram for Atmospheric Radio Refraction
Radio Science, 1967A six‐stage nomogram is presented for determining the refraction of a radio wave entering the earth's atmosphere in terms of surface meteorological conditions and the apparent elevation angle of the incoming wave.
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The Radio Refractive Index of Air
Proceedings of the IRE, 1962This is a tutorial paper. The derivation of the classical Debye expression for the radio refractive index is reviewed. Recent determinations of the constants in this expression are reviewed and the conclusion reached that differences between constants are small compared with the error in using standard meteorological data in the formula.
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A Simple Radio Refractivity Computer
IETE Journal of Research, 1966ABSTRACTA simple electrical circuit analogue designed for use in rapid calculation of atmospheric refractive indices from the Radio Sonde data is described. The circuit yields the dry and wet terms of refractivity separately within ±1N units of accuracy.
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Refractive Indexes of Gases at High Radio Frequencies
Nature, 1941SINCE atmospheric refraction plays an important part in the bending of ultra–short radio waves round the surface of the earth, an adequate study of the propagation of these waves requires a knowledge of the refractive indexes of gases at very high frequencies.
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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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Sensing of radio refractivity and aerosol extinction
Proceedings of IGARSS '94 - 1994 IEEE International Geoscience and Remote Sensing Symposium, 2002Sensing of radio refractivity has historically been accomplished with direct sensing techniques such as radiosondes. While direct sensing techniques provide good data for propagation assessment purposes, remotely sensed data would be more desirable. Various direct and remote sensing techniques and an assessment of their potential operational usefulness
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Refractive scintillation of extragalactic radio sources
AIP Conference Proceedings, 1988Compact extragalactic sources can display intensity fluctuations which are caused by fluctuations in the electron density of the interstellar medium. The 1/e time scale of these ‘‘refractive scintillations’’ can be many years. The intensity structure function D1(τ)=
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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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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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MODELLING OF THE ATMOSPHERIC REFRACTION FOR RADIO WAVES
Survey Review, 1978AbstractThe performance of radio antennas operating at low elevation angles is often limited by atmospheric refraction (angular bending). The bending is due to the change of the index of refraction with height in the atmosphere. It increases with a decreasing elevation angle and can approach a value of 0.7° for an antenna pointing close to the horizon.
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