Results 31 to 40 of about 1,405 (223)

Frequency management system (FMS) for over-the-horizon radar (OTHR) using a near-real-time ionospheric model [PDF]

, 2022
Sky-wave over-the-horizon radar (OTHR) propagates radio waves off the ionosphere to provide long-range surveillance around the Earth's curvature. Frequency selection for high-latitude and polar OTHRs is challenging unless there is an environmental ...
Hannah Villeneuve, Villeneuve, Hannah, Themens, David R.; id_orcid, Warrington, Michael, Michael Warrington, David R. Themens, Thayananthan Thayaparan, Thayaparan, Thayananthan, Fiori, Robyn, Taylor Cameron, Robyn Fiori, Reid, Benjamin; id_orcid, Benjamin Reid, Cameron, Taylor   +13 more
core   +1 more source

Two‐dimensional transmit arrays for polar over‐the‐horizon radar

IET Radar, Sonar & Navigation, 2021
Two‐dimensional (2‐D) transmit arrays offer many advantages over traditional over‐the‐horizon radar (OTHR) arrays, including the capability to steer and mitigate auroral clutter, a clutter type prevalent in polar operation, in all azimuth and elevation ...
Simon Henault, Ryan J. Riddolls
doaj   +1 more source

Multi-Aircraft Formation Recognition Method of Over-the-Horizon Radar Based on Deep Transfer Learning

IEEE Access, 2022
Over-the-horizon radar (OTHR) is an important equipment for the ultralong-range early warning in the military, but the use of constant false-alarm rate (CFAR), which is a traditional detection method, makes it difficult in multi-aircraft formation ...
Futai Liang, Yan Zhou, Hui Li, Xun Feng, Junbiao Zhang   +4 more
doaj   +1 more source

OTHR-23. PATIENT DESIRE TO SHARE DATA AND PARTICIPATE IN RESEARCH IN THE DIPG/DMG COMMUNITY [PDF]

Neuro Oncol
Nicole Lyons, Lisa Wård
europepmc   +3 more sources

OTHR multitarget tracking with a GMRF model of ionospheric parameters [PDF]

Signal Processing, 2021
The ionosphere is the propagation medium for radio waves transmitted by an over-the-horizon radar (OTHR). Ionospheric parameters, typically, virtual ionospheric heights (VIHs), are required to perform coordinate registration for OTHR multitarget tracking and localization.
Zhen Guo, Zengfu Wang, Hua Lan, Quan Pan 0001, Kun Lu   +4 more
openaire   +2 more sources

Overview of ionosphere clutter suppression for high frequency surface wave radar (HFSWR) system: Observation, approaches, challenges and open issue

IET Radar, Sonar &Navigation, Volume 17, Issue 12, Page 1743-1759, December 2023., 2023
An overview of the past and current clutter theoretical models and clutter suppression techniques in the HFSWR system is provided. The experimental results involved in the complex long‐term ionosphere observation are discussed. Special attention is paid to the correlation between the signal degradation sources and eliminating clutter techniques ...
Xiaowei Ji, Xiaochuan Wu, Qiang Yang, Xin Zhang   +3 more
wiley   +1 more source

Evaluation of the effect of sporadic-E on high frequency radio wave propagation in the Arctic [PDF]

, 2022
High Frequency (HF) radio propagation, and applications such as Over-The-Horizon Radar (OTHR), is sensitive to ionospheric disturbances caused by space weather.
T. Thayaparan (12561370), D. Galeschuk (12561371), R.A.D. Fiori (12561362), Themens, D. R.; id_orcid, Thayaparan, T., E.M. Warrington (12561367), Warrington, E. M., Fiori, R. A.D., Galeschuk, D., Cameron, T. G., T.G. Cameron (12561360), D.R. Themens (12561365)   +11 more
core   +2 more sources

Spatial genetic differentiation correlates with species assemblage turnover across tropical reef fish lineages

Global Ecology and Biogeography, Volume 32, Issue 4, Page 535-547, April 2023., 2023
Abstract Aim Evaluating the similarity of diversity patterns across micro‐ to macroevolutionary scales in natural communities, such as species–genetic diversity correlations (SGDCs), may inform on processes shaping community assembly. However, whether SGDCs not only hold across communities but also across lineages has never been explored so far.
Maurine Vilcot, Camille Albouy, Giulia Francesca Azzurra Donati, Thomas Claverie, Pagu Julius, Stéphanie Manel, Loïc Pellissier, Fabien Leprieur   +7 more
wiley   +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

SUBSPACE IMPULSIVE INTERFERENCE SUPPRESSION IN OTHR [PDF]

Progress In Electromagnetics Research C, 2009
This paper proposes a novel subspace projection algorithm for impulsive interference (IMI) suppression in echo samples received by an over-the-horizon radar (OTHR). We particularly highlight the model that the frequency spectrum of IMI component is a complex cosine signal such that IMI cosine can be filtered out by subspace projection.
Tao Liu, Xiaoxu Chen, Jie Wang, Yaohuan Gong   +3 more
openaire   +1 more source