Results 181 to 190 of about 413,548 (214)
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Passive HF Doppler Radar for Oblique-Incidence Ionospheric Sounding
2019 IEEE 2nd Ukraine Conference on Electrical and Computer Engineering (UKRCON), 2019A multi-path multi-frequency passive HF Doppler radar for oblique-incidence sounding the ionosphere, that has been produced in collaboration between researchers at the Harbin Engineering University and V. N. Karazin Kharkiv National University, is briefly described.
Q. Guo +4 more
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Application of the HF Doppler Observations to the Study of Spread‐F
Chinese Journal of Geophysics, 2012AbstractThis paper demonstrates the application of the HF Doppler shift observations to the study on ionospheric Spread‐F with observational cases. These cases show that the HF Doppler shift observation is continuous so that the evolution process of the ionospheric spread‐F can be clearly understood in the view of observations. The HF Doppler frequency
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HF Doppler Acoustic Imaging of the Ocean Surface and Interior
AIP Conference Proceedings, 2004HF phased array Doppler sonar represents a new tool for obtaining Three‐dimensional (r,q,t) images of the oceanic surface and interior velocity field. While the capabilities of the approach are unique, the design constraints are also unusual. Examples of both are presented in this work.
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Analyzing infrasonic disturbances observed by our HF-Doppler detector
2002 3rd International Conference on Microwave and Millimeter Wave Technology, 2002. Proceedings. ICMMT 2002., 2003We have been observing infrasonic disturbances using an HF-Doppler detector. Through analysis of their spectrum structures, it is possible to draw conclusions about local features of infrasonic disturbances occurring in our area.
null Chen JiXiang, null Peng Yong
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An analytical model for the HF backscattered Doppler spectrum for the ocean surface
IEEE Journal of Oceanic Engineering, 1986An analysis previously developed for rough surface scattering with narrow-beam reception is extended to wide-beam or omnidirectional reception. The source is considered to be a pulsed electric dipole. The analysis includes multipathing effects on the received signal.
S. Srivastava, J. Walsh
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HF Doppler Observations of Small Scale Plasma Motions in the Equatorial Electrojet
Physica Scripta, 1986Recordings of the variations in phase path, P of reflections, at vertical incidence, from blanketing sporadic-E layers over Kodaikanal (dip 3.5?N) revealed small amplitude, quasi-sinusoidal oscillations of 45-180 s periods in the time rate of change of phase path, (Doppler frequency).
J Hanumath Sastri +3 more
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Analysis of Effect of Sunrise on Shortwave Communication Using HF-Doppler Detection
2008 China-Japan Joint Microwave Conference, 2008The propagation of the radio wave is seriously affected by the change of the ionosphere in the night. On the basis of the HF-Doppler detection of the ionosphere the basic characteristics of the Doppler frequency shift at sunrise and its effect on the shortwave communication were discussed.
Yinghui Zhang, Yizhuo Wang, Jixiang Chen
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Effects of geomagnetic pulsations on the Doppler shift of HF backscatter radar echoes
Radio Science, 1989The effects of geomagnetic pulsations on the Doppler shifts of HF backscatter radar echoes are studied. Three mechanisms are considered: (1) variation of the phase refractive index under the influence of the varying magnetic component, (2) modulation of the plasma density, and (3) electrodynamic drift of the ionosphere.
A. Bourdillon, J. Delloue, J. Parent
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SVR-based Blind Equalization on HF Channels with a Doppler Spread
2022 International Conference on Artificial Intelligence in Information and Communication (ICAIIC), 2022Soon-Young Kwon +2 more
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Doppler (HF) Radar Facility for Monitoring Dynamic Processes in Geospace
2022 IEEE 41st International Conference on Electronics and Nanotechnology (ELNANO), 2022Leonid F. Chernogor +2 more
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