The Frequency Selective Effect of Radar Backscattering from Multiscale Sea Surface
The Frequency Selective Effect of Radar Backscattering from Multiscale Sea Surface
复制标题
多尺度海面雷达后向散射的频率选择效应
DOI：
10.3390/rs11020160
复制
发表时间：
2019-01
期刊：
影响因子：
5
通讯作者：
Zeng Jiangyuan
中科院分区：
文献类型：
--
作者：
Xie Dengfeng;Chen Kun-Shan;Zeng Jiangyuan
海洋表面基本上包含多尺度粗糙度，其中许多尺寸的毛细波骑在也具有许多尺寸的大尺度波上。利用雷达频率和观测几何形状对雷达后向散射的有效粗糙度尺度的影响是有益的，这样可以更好地理解和量化散射机制和散射源。本文基于常见的海面光谱和理论散射模型，试图达到上述目的。模型预测，选择性粗糙度尺度，进行了比较与广泛的验证数据，包括L波段雷达观测，并预测从C波段和Ku波段的经验模型：地球物理模型功能（CMOD 7）和NASA散射仪（NSCAT-4）的C-和Ku-波段在不同的入射角。数值结果表明，雷达后向散射有效粗糙度尺度随雷达频率和入射角的变化而变化，并与一部分海浪谱分量有关，其下限与由频率和入射角确定的Bragg波数成线性关系，线性关系的尺度因子约为0.05。此外，有效粗糙度的均方根（RMS）高度和相关长度（即，散射源）的有效粗糙度随着入射角的增加而逐渐减小。特别地，相关长度也以3.2的系数线性地依赖于有效波长。此外，这两个系数都与风速、雷达频率和入射角无关。这些结果还揭示了有助于雷达后向散射的光谱分量的基本性质及其随雷达频率和入射角的变化。
The sea surface essentially contains multiscale roughness with capillary waves of many sizes riding on large-scale waves that are also of many sizes. It is instructive to exploit the effect of radar frequency and observation geometry on the effective roughness scales responsible for radar backscattering so that the scattering mechanism and the scattering source can be better understood and quantitated. Based on common sea spectra and a theoretical scattering model, an attempt is made to attain the above objective. Model predictions, with selective roughness scales, are compared with wide validation data, including L-band radar observations, and predictions from C-band and Ku-band empirical models: geophysical model function (CMOD7) and NASA scatterometer (NSCAT-4) for C- and Ku-bands at different incident angles. Numerical results indicate that effective roughness scales for radar backscattering vary with radar frequency and incidence angle and are related to a portion of sea spectral components; the low limit of which is linearly proportional to the Bragg wavenumber determined by frequency and incidence angle, and the scale factor of the linear relationship is about 0.05. In addition, the root mean square (RMS) height and the correlation length of the effective roughness (i.e., scattering source) derived from the effective roughness decrease gradually as incident angle increases. In particular, the correlation length also linearly depends on the effective wavelength with a coefficient of 3.2. Moreover, these two coefficients are both independent of wind speed, radar frequency, and incident angle. These findings also reveal the essential properties of the spectral components contributing to radar backscattering and its variation with radar frequency and incident angle.
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DOI：
10.56236/rss-aa
发表时间：
1977-12
期刊：
--
影响因子：
--
作者：
F. Wentz
通讯作者：
F. Wentz
影响因子：
3.6
作者：
Elfouhaily, T;Chapron, B;Vandemark, D
通讯作者：
Vandemark, D
影响因子：
8.2
作者：
Tzong-Dar Wu;Kun Shan Chen;Jiancheng Shi;Hung-Wei Lee;A. Fung
通讯作者：
Tzong-Dar Wu;Kun Shan Chen;Jiancheng Shi;Hung-Wei Lee;A. Fung
影响因子：
3.4
作者：
M. Brogioni;S. Pettinato;G. Macelloni;S. Paloscia;P. Pampaloni;N. Pierdicca;F. Ticconi
通讯作者：
M. Brogioni;S. Pettinato;G. Macelloni;S. Paloscia;P. Pampaloni;N. Pierdicca;F. Ticconi
DOI：
--
发表时间：
1982-08
期刊：
--
影响因子：
--
作者：
F. Ulaby;R. Moore;A. Fung
通讯作者：
F. Ulaby;R. Moore;A. Fung