Results 41 to 50 of about 1,492 (208)

Enhancing Low‐Latitude Ionospheric Irregularity Prediction With Generalized Linear Models

Space Weather, Volume 24, Issue 3, March 2026.
Abstract The ionosphere poses challenges for accurate forecasting due to its complexity and variability. Irregularities in the lower ionosphere are influenced by local time, season, geographic location, solar activity and space weather, complicating precise predictions.
Alysson Brhian, Marco A. Ridenti, Francisco Azpilicueta, Mauricio Gende, Marisa Roberto   +4 more
wiley   +1 more source

Investigation on the Coherent Component of SHARAD Surface Echo and Surface Roughness: Scaling Behavior and Influence of Hurst Exponent

Earth and Space Science, Volume 13, Issue 2, February 2026.
Abstract The radar surface echo can be separated into coherent and incoherent components by statistical approaches, and the coherent component can be described by a backscattering model related to the RMS height. According to backscattering models for fractal surfaces, the coherent power in decibels decreases with RMS height on a scale independent of ...
Tiansheng Hong, Yan Su, Elena Pettinelli, Roberto Orosei, Sebastian Emanuel Lauro, Zhibin Li, Chunyu Ding, Elisabetta Mattei, Barbara Cosciotti, Chunlai Li   +9 more
wiley   +1 more source

First Order Sea Clutter Cross Section for HF Hybrid Sky-Surface Wave Radar [PDF]

, 2014
This paper presents a modified method to simulate the first order sea clutter cross section for high frequency (HF) hybrid sky-surface wave radar, based on the existent model applied in the bistatic HF surface wave radar.
Li, Y.J., Wei, Y.S., Zhu, Y.P.
core   +1 more source

Order estimation and discrimination between stationary and time-varying (TVAR) autoregressive models [PDF]

, 2007
Copyright © 2007 IEEEFor a set of T independent observations of the same N-variate correlated Gaussian process, we derive a method of estimating the order of an autoregressive (AR) model of this process, regardless of its stationary or time-varying ...
Abramovich, Yuri, Spencer, Nicholas K., Turley, Mike D.   +2 more
core   +1 more source

Low Frequency Oscillation Observed in the Ionosphere Around the Substorm Onsets

Geophysical Research Letters, Volume 53, Issue 2, 28 January 2026.
Abstract Three substorm events in which Defense Meteorological Satellite Program (DMSP) spacecraft are geomagnetically co‐located with substorm onset locations in IMAGE far ultraviolet auroral images are analyzed. A Hilbert‐Huang Transform is used to decompose the DMSP B⊥ ${B}_{\perp }$ in the ionosphere to its intrinsic mode functions. A dominant mode
Simon Wing, Jay R. Johnson, Elmer C. Rivera, Arthur J. Hull, Peter Damiano   +4 more
wiley   +1 more source

Cognitive HF radar

The Journal of Engineering, 2019
Radars operating in the high-frequency (HF) band can exploit propagation modes other than line-of-sight and are hence widely employed to provide over-the-horizon surveillance and remote sensing.
Stuart Anderson
doaj   +1 more source

Accurate and Robust Sensing of the Ionosphere With Uncoded Long Pulse ISR Measurements: 1‐Lag Profile Inversion of Ion Composition and Temperature

Radio Science, Volume 61, Issue 1, January 2026.
Abstract Incoherent scatter radar probing of the topside F‐region ionosphere with reduced electron densities residing at relatively large radar ranges requires the use of uncoded long pulse (ULP) transmissions. In these ULP measurements the range resolution is necessarily poor, rendering the inference of ionospheric state parameters such as composition,
Binghui Wang, Erhan Kudeki, Farzad Kamalabadi, Yulun Wu   +3 more
wiley   +1 more source

Detecting ionospheric TEC perturbations caused by natural hazards using a global network of GPS receivers: The Tohoku case study [PDF]

, 2012
Recent advances in GPS data processing have demonstrated that ground-based GPS receivers are capable of detecting ionospheric TEC perturbations caused by surface-generated Rayleigh, acoustic and gravity waves.
A. J. Mannucci, A. Komjathy, B. Wilson, D. A. Galvan, M. D. Butala, M. Hickey, O. Verkhoglyadova, P. Stephens, V. Akopian   +8 more
core   +2 more sources

Characterization of a Lava Plain NW of Ascraeus Mons, Mars, Through Surface Morphometric Analyses and SHARAD Subsurface Detections

Journal of Geophysical Research: Planets, Volume 131, Issue 1, January 2026.
Abstract The Martian lava plains are characterized by their extensive, low‐relief surfaces, which are the result of numerous basaltic eruptions and feature a variety of volcanic landforms, including vents, cones, pits, and skylights. The combination of these features and impact craters yields a significant understanding of the planet's geological past ...
G. Nodjoumi, S. E. Lauro, M. Valiante, E. Luzzi, A. P. Rossi   +4 more
wiley   +1 more source

The Vertical Ionosphere Parameters Inversion for High Frequency Surface Wave Radar

International Journal of Antennas and Propagation, 2016
High Frequency Surface Wave Radar (HFSWR), which is currently applied in over-the-horizon detection of targets and sea states remote sensing, can receive a huge mass of ionospheric echoes, making it possible for the ionospheric clutter suppression to ...
Xuguang Yang, Changjun Yu, Aijun Liu, Linwei Wang, Taifan Quan   +4 more
doaj   +1 more source