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Modeling on multi‐eigenpath channel in marine atmospheric duct
Radio Science, 2009A multi‐eigenpath channel model is proposed to simulate the microwave transhorizon communication signal in marine atmospheric duct environment. The channel model identifies the relation between multiperiodical delay components and subeigenpath components. The simplified algorithm of subeigen signal is proposed on the basis on signal‐to‐multipath ratio.
Xiao‐long Zhao +2 more
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Analysis of Ultra-short Wave Propagation in Atmospheric Duct
2018 12th International Symposium on Antennas, Propagation and EM Theory (ISAPE), 2018Aiming at the phenomenon of Ship-borne AIS over-the-horizon communication in some area in the Yellow Sea in June 2, 2018, which influenced by atmospheric duct, the atmospheric duct is calculated by using the atmospheric temperature and humidity profiles measured at that time.
Haichuan Tang +3 more
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FNN-Based Prediction of Wireless Channel with Atmospheric Duct
ICC 2021 - IEEE International Conference on Communications, 2021This paper proposes solutions to channel prediction with atmospheric duct based on feedforward neural network (FNN) modeling. Specifically, FNN-based model is to produce accurate prediction by directly learning from large database rather than depending on any assumption.
Hanzhong Zhang +4 more
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On atmospheric humidity and acoustic ducts
The Journal of the Acoustical Society of America, 2018The development of various propagation ducting phenomena (elevated or surface) has been studied extensively for electromagnetic and electro-optical wave propagation. The influence of changes in temperature, pressure, and humidity gradients on the strength and geometry of the duct in the electromagnetic propagation problem is well-documented, and there ...
Joseph F. Vignola +3 more
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The PE solution of natural waveguides in atmosphere: ducts and elevated ducts
Proceedings of MELECON '94. Mediterranean Electrotechnical Conference, 2002The propagation phenomena through 2D surface duct-to-elevated duct transition is described in terms of parabolic equation (PE) method. The split step marching solution of the PE method is first compared with the reference solutions obtained from Helmholtz wave equation in longitudinally invariant surface duct problem and the excellent agreement between
O. Ercan, L. Sevgi
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Doppler ducting of atmospheric gravity waves
Journal of Geophysical Research: Atmospheres, 1986Atmospheric gravity waves are subject to horizontal ducting in a stably stratified atmosphere that contains levels of wind maximum or minimum, quite apart from any superimposed consequences of vertical variation of stability and quite apart from the existence or otherwise of critical levels.
G. Chimonas, C. O. Hines
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The reflection and ducting of atmospheric acoustic-gravity waves
Canadian Journal of Physics, 1965A simple form is derived for the differential equations governing the propagation of acoustic–gravity waves in an atmosphere whose temperature and horizontal wind velocity vary in an arbitrary manner with height. The condition for wave reflection is discussed in some detail, and the W.K.B. approximate solutions are derived and examined.
M. L. V. Pitteway, C. O. Hines
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Journal of Geophysical Research: Atmospheres, 1989
We present simple examples of gravity wave ducting due to the background thermal and velocity structure in the atmosphere and examine the consequences of such ducts lying in close proximity. The dispersion curves for individual thermal and Doppler ducts exhibit similar behavior, with normal and inverse dispersion at higher and lower frequencies ...
David C. Fritts, Li Yuan
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We present simple examples of gravity wave ducting due to the background thermal and velocity structure in the atmosphere and examine the consequences of such ducts lying in close proximity. The dispersion curves for individual thermal and Doppler ducts exhibit similar behavior, with normal and inverse dispersion at higher and lower frequencies ...
David C. Fritts, Li Yuan
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EMI potential of radiowaves in presence of atmospheric ducts
International Journal of Electronics, 1990Radiowave propagation measurements were conducted over a smooth-Earth diffraction path (35 km) between Roorkee and Saharanpur for a period of one year. The data collected were analysed with a view to contribute to the understanding of the propagation phenomenon involved and to provide some physical basis for the prediction techniques to be considered ...
R. K. TEWARI, B. S. JASSAL, M. N. ROY
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The effect of atmospheric ducts on the propagation of AIS signals
Australian Journal of Electrical and Electronics Engineering, 2019Electromagnetic wave propagates abnormally under atmospheric duct conditions. It is very important to study the influence of atmospheric duct on the radio propagation of the shipborne automatic ide...
Wenlong Tang, Hao Cha, Min Wei, Bin Tian
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