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Simulated Climatology of Atmospheric Ducts Over the Persian Gulf
Boundary-Layer Meteorology, 2005A simulated climatology of ducts in the Persian Gulf area was produced with the MM3 atmospheric model. From November to January ducts were sporadic, land and surface based, shallow and weak. From February to October ducts of all types occurred. In the duct season, spatial and temporal variations were related to the land/sea distribution and to day and ...
M. Zhu, B. W. Atkinson
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A narrow-angle parabolic equation model in atmospheric ducts
2016 11th International Symposium on Antennas, Propagation and EM Theory (ISAPE), 2016In this paper, the narrow-angle parabolic equation (NAPE) model applied on atmospheric ducts is solved by using the improved discrete mixed Fourier transform (IDMFT) method which is an efficient form of the split-step Fourier transform (SSFT) algorithm under the impedance boundary conditions.
Yajiao Wang, Lixin Guo, Qingliang Li
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Ducted propagation in the atmosphere, from audible sound to infrasound.
The Journal of the Acoustical Society of America, 2010Earth’s atmosphere supports complicated and highly variable winds and temperature gradients. Temperature inversions and wind jets provide ducts in which sound can propagate efficiently to great distances from the source. Due to the intrinsic variability of the atmospheric winds, these sound ducts are also quite variable, both temporally and spatially ...
Roger Waxler +6 more
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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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Background covariance of atmospheric duct properties based on ensembles
2015 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium), 2015In Refractivity Data Fusion (RDF), the Cartesian representation of refractivity calculated from the Numerical Weather Prediction (NWP) output is mapped into a set of 2-dimensional diagnostic variables which are surfaces over the NWP domain. The diagnostic parameters (e.g. duct base height, duct strength, duct thickness, evaporation duct height) include
Neil D. Gordon +4 more
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Propagation of the transient electromagnetic field above atmospheric surface duct
Applied Mathematics and Computation, 2003zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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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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Tracking atmospheric ducts using radar clutter: evaporation duct tracking using kalman filters
2007 IEEE Antennas and Propagation Society International Symposium, 2007This paper addresses the problem of tracking evaporation ducts in marine environments. The method tracks the evolution of the range and height-dependent index of refraction using the radar sea clutter. A split-step fast Fourier transform (FFT) based parabolic equation (PE) approximation to the wave equation is used to compute the clutter return in ...
Caglar Yardim +2 more
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A Radar Sea Clutter Model for Atmospheric Ducting Conditions
1984Abstract : The Integrated Refractive Effects Prediction System (IREPS) should consider sea clutter effects under atmospheric ducting conditions. The IREPS, undergoing research and development at Naval Ocean Systems Center (NOSC), is intended to provide a shipboard environmental data processing and display capability to assess refractive effects of the ...
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