Results 1 to 10 of about 127,445,565 (301)

Experimental Analysis of Atmospheric Ducts and Navigation Radar Over-the-Horizon Detection

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, Cheng-Guo Liu, Hong-Guang Wang, Qing-Lin Zhu, Li-Jun Zhang, Jie Han, Yu-Sheng Zhang, Qian-Nan Wang   +7 more
doaj   +1 more source

Dynamic Identification Method for Potential Threat Vehicles beyond Line of Sight in Expressway Scenarios

Applied Sciences, 2023
Due to the challenge of limited line of sight in the perception system of intelligent driving vehicles (cameras, radar, body sensors, etc.), which can only perceive threats within a limited range, potential threats outside the line of sight cannot be fed
Fumin Zou, Chenxi Xia, Feng Guo, Xinjian Cai, Qiqin Cai, Guanghao Luo, Ting Ye   +6 more
doaj   +1 more source

A Comparison of the Barrick and Backscatter Ionogram Methods of Calculating Sea Surface Backscatter Coefficients

Remote Sensing, 2022
An understanding of land and sea surface backscatter coefficients at high frequencies (HF) is required to accurately assess ionospheric propagation conditions for over-the-horizon radar.
Danielle Edwards, Manuel Cervera, Andrew MacKinnon   +2 more
doaj   +1 more source

Marine mammal conservation: over the horizon

Endangered Species Research, 2021
Marine mammals can play important ecological roles in aquatic ecosystems, and their presence can be key to community structure and function. Consequently, marine mammals are often considered indicators of ecosystem health and flagship species.
SE Nelms, J Alfaro-Shigueto, JPY Arnould, IC Avila, S Bengtson Nash, E Campbell, MID Carter, T Collins, RJC Currey, C Domit, V Franco-Trecu, MMPB Fuentes, E Gilman, RG Harcourt, EM Hines, AR Hoelzel, SK Hooker, DW Johnston, N Kelkar, JJ Kiszka, KL Laidre, JC Mangel, H Marsh, SM Maxwell, AB Onoufriou, DM Palacios, GJ Pierce, LS Ponnampalam, LJ Porter, DJF Russell, KA Stockin, D Sutaria, N Wambiji, CR Weir, B Wilson, BJ Godley   +35 more
doaj   +1 more source

Phased Feature Extraction Network for Vehicle Search Tasks Based on Cross-Camera for Vehicle–Road Collaborative Perception

Sensors, 2023
The objective of vehicle search is to locate and identify vehicles in uncropped, real-world images, which is the combination of two tasks: vehicle detection and re-identification (Re-ID).
Hai Wang, Yaqing Niu, Long Chen, Yicheng Li, Tong Luo   +4 more
doaj   +1 more source

Long-term over-the-horizon microwave channel measurements and statistical analysis in evaporation ducts over the Yellow Sea

Frontiers in Marine Science, 2023
Maritime high-speed over-the-horizon wireless communication is realizable through evaporation ducts. Detailed measurement, analysis, and modeling of duct channels are essential for application of this communication technique.
Shuwen Wang, Shuwen Wang, Shuwen Wang, Kunde Yang, Kunde Yang, Kunde Yang, Yang Shi, Yang Shi, Hao Zhang, Hao Zhang, Fan Yang, Fan Yang, Fan Yang, Dawei Hu, Dawei Hu, Dawei Hu, Guoyu Dong, Guoyu Dong, Guoyu Dong, Yihang Shu, Yihang Shu, Yihang Shu   +21 more
doaj   +1 more source

Utö Observatory for Analysing Atmospheric Ducting Events over Baltic Coastal and Marine Waters

Remote Sensing, 2023
Maritime safety relies on navigation, detection, and radio communication technologies that function through electromagnetic radiation. Propagation of electromagnetic radiation can be impacted by a disruptive phenomenon known as ducting.
Laura Rautiainen, Jani Tyynelä, Mikko Lensu, Simo Siiriä, Ville Vakkari, Ewan O’Connor, Karoliina Hämäläinen, Harry Lonka, Ken Stenbäck, Jarmo Koistinen, Lauri Laakso   +10 more
doaj   +1 more source

A solution for the over-the-horizon-radar simulator [PDF]

Vojnotehnički Glasnik, 2020
Introduction/purpose: The OTHR simulator presented in this paper is developed and used in practice, with the aim of emulating radar signal environment, but also optimizing the radar parameters in real applications such as: radiated power, antenna ...
Bojan R. Džolić, Mladen Đ. Veinović, Vladimir D. Orlić, Nikola L. Lekić, Nemanja R. Grbić   +4 more
doaj   +1 more source

Seasonal Variation in Land and Sea Surface Backscatter Coefficients at High Frequencies

Remote Sensing, 2022
Over the horizon radars (OTHR) rely on the propagation of high frequency (HF) radio waves via the ionosphere to successfully achieve their designated missions.
Danielle Edwards, Manuel Cervera
doaj   +1 more source

Testing RFoF Link for Transmitting HF-OTHR Signal Between Transmitter and Receiver Shelters

Telfor Journal, 2021
HF-OTHR site contains two equipment shelters, up to 1 km away from each other, that need to be connected for transmitting a FMCW signal. This connection, if realized using a coaxial cable, has shown itself to be vulnerable to external electromagnetic ...
P. Petrović, B. Džolić, N. Lekić, N. Grbić, A. Ćupurdija, V. Orlić, M. Erić   +6 more
doaj   +1 more source