Results 21 to 30 of about 1,807 (203)
Solar-Terrestrial Physics, 2016 Characteristic U-shaped traces (cusps) on ionograms have been identified as off-angle echoes from sloping electron density contours caused by the presence of traveling ionospheric disturbances (TIDs).
Laryunin O.A.
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Polar lacuna on ionograms. E- or F-region processes?
Annales GeophysicaeLacuna on ionograms indicate conditions where the usual ionospheric reflections of vertically propagating radio waves transmitted from and subsequently received by an ionosonde are missing over a range of frequencies.
P. Stauning
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The Accuracy of Real-Time hmF2 Estimation from Ionosondes
Remote Sensing, 2020 A total of 4991 ionograms recorded from April 1997 to December 2017 by the Millstone Hill Digisonde (42.6°N, 288.5°E) were considered, with simultaneous Ne(h)[ISR] profiles recorded by the co-located Incoherent Scatter Radar (ISR).
Carlo Scotto, Dario Sabbagh
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Chaotic Coding for Interference Suppression of Digital Ionosonde
Remote Sensing, 2023 External interference in ionospheric sounding seriously degrades the quality of echo signals and data; thus, it should be eliminated. This paper presents a method for suppressing interference using chaotic coding with a set of Bernoulli map sequences ...
Sijia Han +9 more
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Sporadic-E associated with the Leonid meteor shower event of November 1998 over low and equatorial latitudes [PDF]
Annales Geophysicae, 2001 Rapid radio soundings were made over Ahmedabad, a low latitude station during the period 16–20 November 1998 to study the sporadic-E layer associated with the Leonid shower activity using the KEL Aerospace digital ionosonde.
H. Chandra +6 more
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Electon density profiles of the topside ionosphere
Annals of Geophysics, 2002 The existing uncertainties about the electron density profiles in the topside ionosphere, i.e., in the height region from h m F 2 to ~ 2000 km, require the search for new data sources.
D. Bilitza +3 more
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Ionospheric Behavior of foF2 over Chinese EIA Region and Its Comparison with IRI-2016
Universe, 2020 The ionograms, which were recorded by the ionosonde located at Pu’er station (PUR, 22.7° N, 101.05° E, Dip Latitude 12.9° N) in the Southwest of China in the year of 2016, were used to study the ionospheric behavior of the ordinary critical frequency of ...
Peng Zhu +6 more
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Ionogram scaling using Hidden Markov Models [PDF]
2018 26th Signal Processing and Communications Applications Conference (SIU), 2018 In this paper, a novel method for electron density reconstruction using ionosonde data is proposed. Proposed technique uses Hidden Markov Models for extracting echoes that provides valuable information about electron density distribution in order to provide input to a model based optimization technique that reconstructs the electron density ...
Gokhan Gok +3 more
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Acquirement and analysis of Doppler ionograms with high accuracy in the ionogram mode from Digisonde 256 [PDF]
Radio Science, 2004 The Doppler frequency shift of the radio echo reflected from the ionosphere is an important characteristic to measure ionospheric movements. Generally, for the Digisonde 256 digital ionosonde, a Doppler frequency shift with high resolution can be obtained in the drift mode. In this mode, the height profile of ionospheric disturbances cannot be acquired
Zhigang Yuan +3 more
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Numerical simulation of the propagation of electromagnetic waves in ionospheric irregularities
Earth and Planetary Physics, 2020 The characteristics of high-frequency (HF) electromagnetic (EM) wave propagation can be affected when EM waves propagate in the ionosphere. When ionospheric irregularities appear in the ionosphere, they can have a serious impact on the propagation of HF ...
ChunHua Jiang +4 more
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