Results 21 to 30 of about 2,512 (168)

Temporal Characteristics of P-Band Tomographic Radar Backscatter of a Boreal Forest

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2021
Temporal variations in synthetic aperture radar (SAR) backscatter over forests are of concern for any SAR mission with the goal of estimating forest parameters from SAR data. In this article, a densely sampled, two-year long time series of P-band (420 to
Albert R. Monteith, Lars M. H. Ulander
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Wind redistribution of snow impacts the Ka- and Ku-band radar signatures of Arctic sea ice [PDF]

The Cryosphere, 2023
Wind-driven redistribution of snow on sea ice alters its topography and microstructure, yet the impact of these processes on radar signatures is poorly understood. Here, we examine the effects of snow redistribution over Arctic sea ice on radar waveforms
V. Nandan, V. Nandan, R. Willatt, R. Mallett, R. Mallett, J. Stroeve, J. Stroeve, T. Geldsetzer, R. Scharien, R. Tonboe, J. Yackel, J. Landy, D. Clemens-Sewall, A. Jutila, D. N. Wagner, D. N. Wagner, D. Krampe, M. Huntemann, M. Mahmud, D. Jensen, T. Newman, S. Hendricks, G. Spreen, A. Macfarlane, M. Schneebeli, J. Mead, R. Ricker, M. Gallagher, C. Duguay, C. Duguay, I. Raphael, C. Polashenski, M. Tsamados, I. Matero, M. Hoppmann   +34 more
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A comparison of overshoot modelling with observations of polar mesospheric summer echoes at radar frequencies of 56 and 224 MHz [PDF]

Annales Geophysicae, 2015
We have compared radar observations of polar mesospheric summer echoes (PMSEs) modulated by artificial electron heating, at frequencies of 224 MHz (EISCAT VHF) and 56 MHz (MORRO). We have concentrated on 1 day of observation, lasting ~ 3.8 h.
O. Havnes, H. Pinedo, C. La Hoz, A. Senior, T. W. Hartquist, M. T. Rietveld, M. J. Kosch, M. J. Kosch   +7 more
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Radiometric Comparison within the Sentinel-1 SAR Constellation over a Wide Backscatter Range

Remote Sensing, 2020
Radiometric calibration adjusts the measured pixel intensity to a physical property, the radar cross section (RCS). After calibration, this relationship is defined over the entire backscatter range: from low image power (near noise) up to high ...
Kersten Schmidt, Marco Schwerdt, Nuno Miranda, Jens Reimann   +3 more
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HF radar backscatter inversion technique [PDF]

Radio Science, 2006
Methods of inverting high‐frequency radar land and sea backscatter to obtain ionospheric vertical profiles offer an important means of remote sensing the ionosphere up to thousands of kilometers from the transmitter/receiver location. This new inversion technique requires the received elevation angle as well as the time delay or group path of the ...
Norman, Robert., Dyson, Peter.
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Physics-Based Forward Modeling of Ocean Surface Swell Effects on SMAP L1-C NRCS Observations

Sensors, 2022
This paper examines the impact of ocean surface swell waves on near-coastal L-band high-resolution synthetic aperture radar (SAR) data collected using the National Aeronautics and Space Administration’s (NASA) Soil Moisture Active/Passive (SMAP) radar at
Shanka N. Wijesundara, Joel T. Johnson
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Optical, radar, and magnetic observations of magnetosheath plasma capture during a positive IMF B_z impulse [PDF]

Annales Geophysicae, 2008
We present a multi-instrument study of the ionospheric response to a northward turning of the IMF. The observations were made in the near-noon (11:00 MLT) sector on Svalbard (at 75° MLAT).
V. Safargaleev, A. Kozlovsky, A. Kozlovsky, T. Sergienko, T. K. Yeoman, M. Uspensky, D. M. Wright, H. Nilsson, T. Turunen, A. Kotikov   +9 more
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The spectral characteristics of E-region radar echoes co-located with and adjacent to visual auroral arcs [PDF]

Annales Geophysicae, 2002
Simultaneous all-sky camera and HF radar observations of the visual and E-region radar aurora in the west-ward electrojet suggest a close relationship between a pair of parallel east-west-aligned auroral arcs, separated by ~ 30 km, and a region of ...
S. E. Milan, S. E. Milan, N. Sato, M. Lester, T. K. Yeoman, Y. Murata, H. Doi, T. Saemundsson   +7 more
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Anomalous radar backscatter from Titan’s surface? [PDF]

Icarus, 2011
Abstract Since Cassini arrived at Saturn in 2004, its moon Titan has been thoroughly mapped by the RADAR instrument at 2-cm wavelength, in both active and passive modes. Some regions on Titan, including Xanadu and various bright hummocky bright terrains, contain surfaces that are among the most radar-bright encountered in the Solar System.
M.A. Janssen, A. Le Gall, L.C. Wye
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Using Generalized Regression Neural Network to Retrieve Bare Surface Soil Moisture From Radarsat-2 Backscatter Observations, Regardless of Roughness Effect

Frontiers in Earth Science, 2021
The combined influence of surface soil moisture and roughness on radar backscatters has been limiting SAR’s application in soil moisture retrieval. In the past research, multi-temporal analysis and artificial neural network (ANN) inversion of physically ...
Ling Zeng, Quanming Liu, Linhai Jing, Ling Lan, Jun Feng   +4 more
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