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The Statistical Characteristics of Atmospheric Ducts Observed Over Stations in Different Regions of American Mainland Based on High-Resolution GPS Radiosonde Soundings [PDF]
Frontiers in Environmental Science, 2022 Atmospheric duct is an anomalous atmospheric structure that affects electromagnetic wave propagation. The important characteristics of the atmospheric ducts include duct probability, duct height, duct strength, and the thickness of the trapping layer. To
Lang Huang, Xiaofeng Zhao, Yudi Liu
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Atmospheric Duct Detection Using Wind Profiler Radar and RASS [PDF]
Journal of Atmospheric and Oceanic Technology, 2019 AbstractA method of detecting atmospheric ducts using a wind profiler radar (WPR) and a radio acoustic sounding system (RASS) is proposed. The method uses the RASS to measure the virtual temperature profile and calculate the Brunt–Väisälä frequency; it also uses the WPR to measure the spectral width of the atmosphere and the atmospheric refractive ...
Hua Wang +4 more
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Characterizing Evaporation Ducts Within the Marine Atmospheric Boundary Layer Using Artificial Neural Networks [PDF]
, 2019 We apply a multilayer perceptron machine learning (ML) regression approach to infer electromagnetic (EM) duct heights within the marine atmospheric boundary layer (MABL) using sparsely sampled EM propagation data obtained within a bistatic context.
Hilarie Sit, Christopher Earls
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Gaussian Process Regression for Estimating EM Ducting Within the Marine Atmospheric Boundary Layer [PDF]
, 2020 We show that Gaussian process regression (GPR) can be used to infer the electromagnetic (EM) duct height within the marine atmospheric boundary layer (MABL) from sparsely sampled propagation factors within the context of bistatic radars.
Hilarie Sit, Christopher J. Earls
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Experimental Analysis of Atmospheric Ducts and Navigation Radar Over-the-Horizon Detection [PDF]
Remote Sensing, 2022 Since the height of sea detection radar antenna and ship targets is relatively low, it is generally believed that its over-the-horizon detection is mainly caused by the evaporation duct at sea.
Li-Feng Huang +7 more
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Arctic Atmospheric Ducting Characteristics and Their Connections with Arctic Oscillation and Sea Ice [PDF]
Atmosphere, 2022 Atmospheric ducting is an anomalous atmospheric structure that affects electromagnetic wave propagation. In the context of global warming, the navigation capacity of the Arctic is increased, and the atmospheric duct can affect communication and ...
Ting Qin +6 more
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Ducting Approach to Atmospheric Sound Propagation [PDF]
The Journal of the Acoustical Society of America, 1969 The velocity profile V=V0/1+Az+Bz2)12 is investigated for nonfocus situations. When A is negative, sound rays are refracted back to the ground and are reflected. When A is positive, sound rays are refracted away from the ground and a shadow zone is formed.
Robert C. Polly
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The detectable double atmospheric ducts for RFC [PDF]
2014 IEEE Antennas and Propagation Society International Symposium (APSURSI), 2014 Refractivity from clutter (RFC) systems are defined for retrieving the atmospheric ducts from the sea clutter echo of a radar in open sea or coastal environment. However, some ducts hardly have an effect on the clutter echo. Consequently, the RFC technique suffers inherent limitations and is unable to provide information about these ducts.
Douvenot, Rémi +2 more
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Low-Level Atmospheric Ducts [PDF]
Nature, 1948 DURING 1943-46, the Signals Research and Development Establishment operated a series of experimental centimetre-wave radio links along a 60-mile oversea path across Cardigan Bay. One major purpose of the investigation, which was carried out for an inter-Service committee under the chairmanship of Sir Edward Appleton, was to determine the degree to ...
J. S. MCPETRIE, B. STARNECKI
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Arctic, Antarctic, and Alpine Research, 2022 Atmospheric ducts could disturb radar detection and radio communication in the Arctic and risk increasing human activities under Arctic warming. It is an urgent need to understand atmospheric ducts in the Arctic, with distinct atmospheric systems and ...
Jinhuan Zhu +6 more
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