Results 11 to 20 of about 452,012 (153)
Ionospheric Doppler measurements by means of HF-radar techniques [PDF]
Annals of Geophysics, 2005 Studies of the dynamics of the ionosphere and its related phenomena are mainly based on Doppler Drift measurements. The time variation (ionisation/recombination) of plasma density, thermospheric wind and others can be observed by means of HF-radars.
D. Altadill, C. Bianchi
doaj +4 more sources
Digital radio and its application in the HF (2-30 MHz) band [PDF]
, 2004 The propagation environment at high frequencies (HF, 2-30 MHz) has a significant impact on the performance of radio systems (especially data communications).
Davies, Nigel Clement
core +9 more sources
Modern spectral analysis in HF radar remote sensing. [PDF]
, 1998 High-Frequency (HF) radar systems are currently used to collect wave data. By applying spectral analysis methods, such as the Fast Fourier Transform (FFT) method, to the radar backscatter from the ocean surface, the so-called Doppler spectrum is ...
Vizinho, A
core +6 more sources
High-Frequency Channel Modeling Based on the Multi-Source Ionospheric Assimilation Model
Remote Sensing, 2022 In this paper, we explored how to more accurately predict the quality of high-frequency links and how to better research and improve the capabilities of high-frequency communication, reconnaissance, and positioning systems.
Mingjie Lv +7 more
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CHARACTERISTIC FEATURES OF VARIATIONS IN HF RADIO WAVE PARAMETERS IN THE IONOSPHERE DURING THE COURSE OF THE SOLAR ECLIPSE OF JUNE 21, 2020 OVER THE PEOPLE’S REPUBLIC OF CHINA [PDF]
Radio Physics and Radio Astronomy, 2022 Subject and Purpose. The study of the effect that each new Solar eclipse (SE) has on radio wave characteristics is an actual scientific and technical issue.
L. F. Chernogor +5 more
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Earth, Planets and Space, 2023 The explosive eruption of the Hunga Tonga-Hunga Ha’apai volcano on 15 January 2022 generated atmospheric waves traveling around the Earth, which caused ionospheric disturbances on various spatio-temporal scales.
Hiroyuki Nakata +4 more
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Український антарктичний журнал, 2023 The paper aims at an experimental study of the mechanisms of long-distance high-frequency (HF) propagation and spatial and temporal variations of the ionospheric parameters during the first hours of a severe geomagnetic storm of April 23, 2023 by ...
A. Zalizovski +11 more
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Remote Sensing, 2021 We discuss results on plasma density profile modifications in the F-region ionosphere that are caused by HF heating with the frequency f0 in the range [(−150 kHz)–(+75 kHz)] around the fourth electron gyroharmonic 4fc.
Alexey V. Shindin +7 more
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Letter to the editor
CUTLASS observations of a high-m ULF wave and its consequences for the DOPE HF Doppler sounder [PDF]
Annales Geophysicae, 1999 The CUTLASS (Co-operative UK Twin Located Auroral Sounding System) Finland HF radar, whilst operating in a high spatial and temporal resolution mode, has measured the ionospheric signature of a naturally occurring ULF wave in scatter artificially ...
D. M. Wright, D. M. Wright, T. K. Yeoman
doaj +1 more source
Observations of Pc 3-4 and Pi 2 geomagnetic pulsations in the low-latitude ionosphere [PDF]
Annales Geophysicae, 1999 Day-time Pc 3–4 (~5–60 mHz) and night-time Pi 2 (~5–20 mHz) ULF waves propagating down through the ionosphere can cause oscillations in the Doppler shift of HF radio transmissions that are correlated with the magnetic pulsations recorded on the ground.
R. A. Marshall +4 more
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