Results 191 to 200 of about 8,136,705 (229)

Observation of tide from X-band marine radar image sequences

2016 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 2016
Tide has been monitored by tide-gauge stations and spaceborne radar altimeters. A new method to estimate the characteristics of coastal tide from X-band marine radar image sequences is proposed. The significant wave height (SWH) is firstly retrieved from X-band marine radar image sequence, and then filtered to remove the influences of noises.
Zhongbiao Chen, Yijun He 0004, Jiayi Pan 0001, Biao Zhang 0001, Xiaoqing Chu   +4 more
openaire   +1 more source

Rain Detection From X-Band Marine Radar Images

2019 IEEE Radar Conference (RadarConf), 2019
A method based on support vector machines (SVMs) is proposed to detect rain from X-band marine radar images. First, each image is labeled as rain-free or rain-contaminated according to the simultaneous rain rate data provided by a rain gauge. Then, feature vector is extracted from each image, which consists of the normalized histogram bin values.
Xinwei Chen, Weimin Huang
openaire   +1 more source

Pulse Compression for an X-band Marine Wave-Sensing Radar

OCEANS 2019 MTS/IEEE SEATTLE, 2019
As part of the Office of Naval Research's Environmental and Ship-Motion Forecasting project, we have developed a four-antenna vertically-polarized coherent X-band radar to measure the orbital Doppler velocities of the sea-surface. This Advanced Wave-Sensing Radar (AWSR) initially used a gated CW pulse to radiate the scatterers using a traveling-wave ...
John M Mower, Gordon Farquharson, Brad Frazer, John G Kusters   +3 more
openaire   +1 more source

An Algorithm for Wind Direction Retrieval From X-Band Marine Radar Images

IEEE Geoscience and Remote Sensing Letters, 2016
A new method for retrieving wind direction from X-band marine radar images is presented in this letter. The new algorithm investigates radar backscatter in the wavenumber domain and obtains wind direction from the wavenumber spectrum. Different from previous algorithms that detect rain-contaminated images and discard them, the new algorithm could be ...
Yali Wang, Weimin Huang 0001
openaire   +1 more source

Nonparametric background model based clutter map for X-band marine radar

2015 IEEE International Conference on Image Processing (ICIP), 2015
In a radar system, clutter means any echoes which are not scattered by the wanted target. Usually, the radar clutter map stores an average level for each point or cell in the range-azimuth coordinates as the reference value. A target is then detected in a range-azimuth region if the new echo value in that region exceeds the average background level. In
Yi Zhou 0011, Xiaoming Liu, Jidong Suo, Chang Liu, Xiaohong Su, Limei Liu   +5 more
openaire   +2 more sources

On Shipboard Marine X-Band Radar Near-Surface Current ‘‘Calibration’’

Journal of Atmospheric and Oceanic Technology, 2015
AbstractThe ocean wave signatures within conventional noncoherent marine X-band radar (MR) image sequences can be used to derive near-surface current information. On ships, an accurate near-real-time record of the near-surface current could improve navigational safety. It could also advance understanding of air–sea interaction processes.
Björn Lund, Hans C. Graber, Katrin Hessner, Neil J. Williams   +3 more
openaire   +1 more source

The measurement of sea surface profile with X-band coherent marine radar

Acta Oceanologica Sinica, 2015
The line-of-sight velocity of scattering facets is related to the Doppler signals of X-band coherent marine radar from the oceanic surface. First, the sign Doppler Estimator is applied to estimate the Doppler shift of each radar resolution cell. And then, in terms of the Doppler shift, a retrieval algorithm extracting the vertical displacement of the ...
Yunhua Wang, Huimin Li, Yanmin Zhang, Lixin Guo   +3 more
openaire   +1 more source

Multi-directional wave spectra from marine X-band radar

Ocean Dynamics, 2016
The signal measured by heave–pitch–roll directional wave buoys yields the first four coefficients of a Fourier series. Data adaptive methods must be employed to estimate a directional wave spectrum. Marine X-band radars (MRs) have the advantage over buoys that they can measure “model-free” two-dimensional (2D) wave spectra.
Björn Lund, Clarence O. Collins, Hitoshi Tamura, Hans C. Graber   +3 more
openaire   +1 more source

Near-surface current shear measured by marine X-band radar

2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM), 2015
This paper presents a new method to measure the near-surface currents' vertical shear by marine X-band radar (MR). The data used here were acquired from R/V Roger Revelle during the Impact of Typhoons on the Ocean in the Pacific (ITOP) field campaign in 2010.
Björn Lund, Hans C. Graber, Jeffrey Campana, Eric Terrill   +3 more
openaire   +1 more source

X band patch array antenna design for marine radar application

2018 22nd International Microwave and Radar Conference (MIKON), 2018
Horizontally polarized patch antenna array design is proposed for frequency modulated continuous wave (FMCW) marine radar applications. The array consists of series-parallel fed 96 elements printed on microwave substrate. The array configuration is optimized for minimum line loss and maximum aperture efficiency. The target frequency band is 9.3–9.4 GHz.
Pehlivan M., Asci Y., Yegin K., Ozdemir C.   +3 more
openaire   +2 more sources