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The Impact of Evaporative Ducting on Covert Communications
MILCOM 2007 - IEEE Military Communications Conference, 2007This paper provides a brief primer on tropospheric ducting and examines the potential impact that evaporative ducting has on the intercept vulnerability of covert communication systems. The study considers the intercept vulnerability of a generic ship-based satellite terminal in the presence of evaporative ducting when the threat consists of a total ...
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Lidar description of the evaporative duct in ocean environments
SPIE Proceedings, 2005The description of radar propagation in the presence of the evaporation duct has proven to be a difficult problem in both littoral and open ocean environments. To properly characterize the propagation of a radar beam at low elevation angles, the evaporation duct must be located and scattering properties quantified.
Adam Willitsford, C. R. Philbrick
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Practical application of an evaporation duct model
Radio Science, 1985The application of an evaporation duct model in operational and climatological assessments of propagation and the sensitivity of the model to meteorological measurements are examined. The unexpectedly frequent occurrence of evaporation duct heights greater than 40 m is related to thermally stable conditions in the atmospheric surface layer.
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The research of radio wave propagation in the evaporation duct
2009 3rd IEEE International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications, 2009In this paper, a valid and accurate method is presented that accounts for the characteristics of radio wave propagation in the evaporation duct using the Model method. The model assumes a trilinear refractivity profile and the layer to be stationary and horizontally homogeneous, using the model program calculations the height gain and path loss for ...
Miao Zhong +3 more
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Study on Wireless Detection in Condition of Evaporation Duct
2009 5th International Conference on Wireless Communications, Networking and Mobile Computing, 2009Evaporation duct is a layer of air just above the sea surface which can trap wireless energy. It is created by the rapid decrease of humidity with height just above the sea surface. Owing to it, the path of wireless wave is changed remarkably, the wireless detection range will be increased to realize the phenomenon of OTH (over-the-horizon) detection ...
Bin Tian, Hao Cha, Jie Li, Mo Zhou
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Investigations into the occurrence of evaporation ducts near Karachi
2017 International Conference on Communication Technologies (ComTech), 2017Refraction through the atmosphere is one of the propagation mechanisms of wireless signals traversing the atmosphere. Different refractive conditions can be prevalent at a particular place, height and time, depending on the weather conditions. Ducting and sub-refractive conditions can lead to Anomalous Propagation (ANAPROP).
Saeed Ur Rehman, Naveed Mufti
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Transhorizon radiowave propagation due to evaporation ducting
Resonance, 2006A detailed description of evaporation ducts and their relevance to radiowave propagation over the sea has been presented. The constantly changing weather conditions over the sea mean that marine and coastal environments, in particular, are prone to these unusual tropospheric phenomena that facilitate radio waves to have higher signal strengths and to ...
Gunashekar, S. D. +2 more
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Optimal Antenna Position Inside Evaporation Duct
2018 IEEE Radio and Antenna Days of the Indian Ocean (RADIO), 2018This paper is devoted to the investigation of an evaporation duct in the context of its impact on microwave links communication stability. The work contains the numerical results for previously developed mathematical model based on using the method of dyadic Green's functions.
Denis Serebriakov, Renat Abdullin
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Determination of evaporation duct heights by an inverse method
SPIE Proceedings, 2007The detection and tracking of naval targets, including low RCS objects like inflatable boats requires a thorough knowledge of the propagation properties of the maritime boundary layer. Models are in existence, which allow a prediction of the propagation factor using the parabolic equation algorithm.
R. Douvenot +6 more
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Polarization dependence of transient signals in evaporation ducts
Radio Science, 1978The evaporation duct model used is that of Kahan and Eckart and consists of a discontinuous drop of the otherwise constant relative permittivity at the upper duct boundary. The earth is assumed to be a perfect conductor and ideally plane. We determine the electrical field strength exactly at some fixed point within the duct layer, having chosen a ...
H. Zimmer +2 more
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