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Evaporation duct estimation from clutter using meteorological statistics
2008 IEEE Antennas and Propagation Society International Symposium, 2008Many of the lower atmospheric maritime radar systems have to operate under ducting conditions. Electromagnetic ducts result in non-standard electromagnetic propagation which can fundamentally change the performance of the system that is designed to operate under standard atmospheric conditions.
C. Yardim, P. Gerstoft, W.S. Hodgkiss
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Propagation Theory for the Evaporation Duct
1973Propagation in radio ducts first attracted attention during the 1940’s and was the subjectof some notable theoretical studies (1),(2),(3).Recent developments such as the use of the Monin-Obukhov similarity theory(4) to give realistic refractive index models, improvements in theoretical and numerical methods and the need to incorporate other phenomena ...
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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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Influence of evaporation ducts on radar sea return
IEE Proceedings F Radar and Signal Processing, 1990Modelling of radar sea return is discussed with consideration of propagation conditions. Both the intensity and propagation direction of energy incident at the sea surface can be significantly affected by the refractive condition of the atmosphere. The authors describe and evaluate a model that incorporates both of these effects for the situation where
J.P. Reilly, G.D. Dockery
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Evaporation ducts observed during the TAPS 2013 campaign
2015 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium), 2015The Tropical Air-Sea Propagation Study (TAPS) was an experimental campaign that took place in the northern coast of Queensland, Australia between the 25th of November and 5th of December 2013. The main objectives of TAPS concern the validation of mesoscale NWP models (including surface layer models) in a tropical littoral environment and also the ...
Claverie, Jacques +4 more
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Simulation of microwave propagation in turbulent evaporation duct
2012 6th European Conference on Antennas and Propagation (EUCAP), 2012The method to account for turbulent refractivity fluctuations for split-step parabolic equation Fourier method are presented. The results of microwave propagation simulations in an evaporation duct with account for scattering by correlated turbulent fluctuations of the tropospheric refractivity index is analyzed.
Iurii Levadnyi +2 more
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Estimation of Evaporation Duct and Surface-Based Duct Parameters from a Combined Refractivity Model
2018 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting, 2018The study of atmospheric refractive conditions is essential in the shipboard radars and radio communication conditions in the maritime environment. Especially at low altitudes, as radio refractivity can vary considerably with both height and range, characterizing marine atmospheric boundary layer properties, ducting in particular, is thus crucial for ...
Qi Wang +8 more
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Evaporation Duct Channel Model for Flat Sea
2023 17th European Conference on Antennas and Propagation (EuCAP), 2023Sebastian Kudera +2 more
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Comparison of evaporation duct and path loss models
Radio Science, 1985This paper will evaluate the current meteorological measurement techniques used to infer the evaporation‐ducting process. Included within this study is a comparison of relative performance, sensitivities to meteorological inputs, and ease of computation for three standard evaporation duct models and two electromagnetic wave propagation models.
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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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