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Atmospheric Ducting Effect in Wireless Communications: Challenges and Opportunities
Journal of Communications and Information Networks, 2021Atmospheric ducting has a significant impact on electromagnetic wave propagation. Radio signals that are trapped and guided by the atmospheric duct can travel a much longer distance over the horizon with lower attenuation since the signal power does not spread isotropically through the atmosphere.
Fangfang Liu 0008 +3 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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Application of satellite data assimilation in monitoring the atmospheric duct
Earth Observing Systems XXIV, 2019Yanan Liu
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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 (35Â 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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Prediction of Electromagnetic Shadow Zone in Atmospheric Duct
The 2006 4th Asia-Pacific Conference on Environmental Electromagnetics, 2006Electromagnetic shadow zone is an important propagation character which is caused by atmospheric duct. The purpose of this paper is to find a method to predict such shadow zone. Two numerical models are introduced in this paper. The first one is used to predict the top hole in evaporation duct. The other one is to predict the skip zone in surface duct.
Jiao Lin, Wang Hua, Zhang Yong-gang
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