Title
Estimation of Sea Surface Current from X-Band Marine Radar Images by Cross-Spectrum Analysis
Abstract
The cross-spectral correlation approach has been used to estimate the wave spectrum from optical and radar images. This work aims to improve the cross-spectral approach to derive current velocity from the X-band marine radar image sequence, and evaluate the application conditions of the method. To reduce the dependency of gray levels on range and azimuth, radar images are preprocessed by the contrast-limited adaptive histogram equalization. Two-dimensional cross-spectral coherence and phase are derived from neighboring X-band marine radar images, and the phases with large coherences are used to estimate the phase velocity and angular frequency of waves, which are first fitted with the theoretical dispersion relation by different least square models, and then the current velocity can be determined. Compared with the current velocities measured by a current meter, the root-mean-square error, correlation coefficient, bias, and relative error are 0.15 m/s. 0.88, -0.05 m/s, and 7.79% for the north-south velocity, and 0.14 m/s, 0.86, 0.06 m/s, and 10.75% for the east-west velocity in the experimental area, respectively. The preprocessing, critical coherence, and the number of images for applying the cross-spectral approach, are discussed.
Year
DOI
Venue
2019
10.3390/rs11091031
REMOTE SENSING
Keywords
Field
DocType
X-band marine radar,sea surface current,nearshore,cross-spectrum
Remote sensing,Cross-spectrum,Marine radar,Geology,X band
Journal
Volume
Issue
ISSN
11
9
2072-4292
Citations 
PageRank 
References 
0
0.34
0
Authors
5
Name
Order
Citations
PageRank
Zhongbiao Chen161.54
Biao Zhang29723.66
Vladimir N. Kudryavtsev302.03
Yijun He416842.09
Xiaoqing Chu500.34