| 摘要: |
| 中国南海是内波频发海域，卫星遥感在内波参数特征的统计分析中得到了广泛应用，但是卫星轨道的重复访问时间长，不能连续观测内波参数的变化特征。X波段海洋雷达具有高时间和空间分辨率，可以长期连续观测内波的变化，本文提出了利用X波段海洋雷达图像提取内波参数的方法，并利用连续观测的数据研究了各参数的分布特征。首先，对雷达图像进行预处理，包括平均处理及斜坡校正两步；利用二维快速傅里叶变换确定内波的传播方向，进而根据该方向上的径向廓线确定内波的相速度大小、波长及周期。最后，利用在南海石油平台上观测的X波段雷达图像对内波各参数进行提取和统计分析，结果表明，研究区域内波的传播方向多为西北向及西向传播，相速度多为0.6–0.8 m/s，波长一般为400–600 m，周期大部分不超过1000 s。 |
| 关键词: 海洋内波 南海西北部 X波段海洋雷达 参数统计 |
| DOI： |
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| 基金项目:国家自然科学基金项目（面上项目，重点项目，重大项目） |
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| Study on the Characteristics of Internal Wave Parameters in Northwestern South China Sea Based on X-band Marine Radar |
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wenjinghan1,2, heyijun1,2, chenzhongbiao1,2
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1.Nanjing University of Information Science &2.Technology
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| Abstract: |
| Internal waves (IWs) occur frequently in the South China Sea (SCS), and the satellite remote sensing images have been widely used to study the characteristics of IW parameters. However, the repeated access time of satellite orbit is long, thus the characteristics of IW parameters cannot be continuously observed. X-band marine radar has high temporal resolution and spatial resolution, which can observe the change of IWs continuously. In this paper, a method of determining IW parameters from X-band marine radar images is proposed, and then the characteristics of each parameter is studied by using continuous observation data. Firstly, X-band marine radar image is preprocessed by averaging and ramp correction. The propagation direction of IW is determined by two-dimensional fast Fourier transform, and the parameters of the IW are determined by the radial profile in this direction, such as the phase velocity, wavelength and period. Finally, the X-band radar images observed on the SCS oil platform are used to extract and statistically analyze the parameters of IWs. The results show that the propagation directions of IWs in the study area are mostly northwest and west, the phase velocities are mostly in 0.6–0.8 m/s, the wavelengths are generally in 400–600 m, and the periods are mostly less than 1000 s. |
| Key words: internal wave the northwestern South China Sea X-band marine radar parametric statistics |