Global Morphology of Ionospheric Scintillations II
Global Morphology of Ionospheric Scintillations II

Author: Jules Aarons

Publisher:

Published: 1975

Total Pages: 30

ISBN-13:

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Updating a review of the global morphology of ionospheric scintillations published in 1971, this study adds additional experimental studies on familiar topics to newer types of measurements of ionospheric irregularities, including in situ experiments and artificial heating of the F-layer.

Global Morphology of Ionospheric Scintillations
Global Morphology of Ionospheric Scintillations

Author: Jules Aarons

Publisher:

Published: 1970

Total Pages: 48

ISBN-13:

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Amplitude fluctuations produced by small irregularities in electron density in the F-layer of the ionosphere (at 300 to 400 km height) can be a problem to communication and navigation systems in the VHF-UHF range. Recent measurements, primarily by AFCRL, are shown with emphasis on results at high and equatorial latitudes. At high latitudes an irregularity region exists whose lower boundary reaches 57 degrees invariant latitude near midnight. During magnetic storms the boundary descends to lower latitudes and the fading becomes deeper. Over the polar cap scintillations are somewhat diminished. When observing synchronous satellites through the irregularity region, deep and fast fading is frequently seen, with fade rates to one per second. Irregularities produce deep scintillations in the VHF range plus or minus 15 degrees from the geomagnetic equator. In equatorial regions maximum occurrence of high level scintillations takes place between 2100 and 2400 local time during the equinoxes; a minimum occurrence is observed during the solstices. When the sunspot number decreases, the equatorial irregularity region spreads and becomes larger. The data for various latitudes has been placed in statistical form, that is, distribution of amplitudes for 15-min samples as well as for periods of 1 yr and longer. (Author).

Equatorial Scintillations
Equatorial Scintillations

Author: Jules Aarons

Publisher:

Published: 1976

Total Pages: 40

ISBN-13:

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With the advent of satellite communications systems at frequencies varying from approx. 140 to 1600 MHz, as well as navigation and ranging systems in the 1200 to 1600-MHz portions of the spectrum, the effect of equatorial irregularities on fading signals has become of importance. Recent observations of the signal statistics of scintillations at frequencies ranging from 136 MHz to 6 GHz reveal a power-law falloff of irregularity sizes. Power spectra are now available for a variety of conditions and for frequencies from vhf to microwaves. during periods of intense equatorial activity at frequencies to 360 MHz, Rayleigh scattering is frequently experienced.

Space Physics and Aeronomy, Ionosphere Dynamics and Applications
Space Physics and Aeronomy, Ionosphere Dynamics and Applications

Author: Chao Huang

Publisher: John Wiley & Sons

Published: 2021-05-11

Total Pages: 47

ISBN-13: 1119507553

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A comprehensive review of global ionospheric research from the polar caps to equatorial regions It's more than a century since scientists first identified the ionosphere, the layer of the Earth’s upper atmosphere that is ionized by solar and cosmic radiation. Our understanding of this dynamic part of the near-Earth space environment has greatly advanced in recent years thanks to new observational technologies, improved numerical models, and powerful computing capabilities. Ionosphere Dynamics and Applications provides a comprehensive overview of historic developments, recent advances, and future directions in ionospheric research. Volume highlights include: Behavior of the ionosphere in different regions from the poles to the equator Distinct characteristics of the high-, mid-, and low-latitude ionosphere Observational results from ground- and space-based instruments Ionospheric impacts on radio signals and satellite operations How earthquakes and tsunamis on Earth cause disturbances in the ionosphere The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals. Find out more about the Space Physics and Aeronomy collection in this Q&A with the Editors in Chief