基于机载波谱仪数据的海浪斜率与海浪方向谱反演研究

发布时间：2018-05-19 01:19

本文选题：海洋波谱仪 + 斜率概率密度函数　；参考：《华中科技大学》2016年硕士论文

【摘要】：气象、航海、造船、海洋工程等领域,都需要高精度的实时海浪信息。海浪方向谱是重要的海浪信息,某时某地海洋波浪场的统计特征(波高,波长,波周期,波向,波陡等)均可由海浪方向谱计算得到,因此海浪方向谱的获取极为重要。海浪波谱仪是专门为海浪方向谱探测而设计的新型微波传感器,是一种小入射角360°方位向旋转扫描的真实孔径雷达。2018年世界上第一台星载波谱仪SWIM(Surface Wave Investigation and Monitoring)将随中法海洋星发射升空。本文研究了利用机载波谱仪实测数据进行海浪方向谱反演。针对机载情况下入射角范围较大的问题,首先讨论了调制信号的提取方法;然后,鉴于斑点噪声对海浪谱反演性能的重要影响,重点研究了波谱仪海面斑点噪声的形成机理、统计特性和去除方法;从波谱仪实测数据中反演出海浪方向谱,并将反演结果与浮标数据进行了对比验证。本文的另一个主要研究内容是利用波谱仪数据实现海浪斜率反演。海浪斜率是海/气界面基本的物理参数,但目前还缺乏大范围的直接测量手段。波谱仪特有的工作方式,能够获取小入射角下海面随入射角和方位角变化的二维散射数据,使得海浪斜率的遥感成为可能。本文基于准镜像散射近似模型建立了波谱仪海浪斜率反演模型,并通过与小入射角海面精确散射模型——物理光学模型的仿真计算结果对比,确定了斜率反演模型的入射角适用范围。通过非线性最小二乘二维反演方法,从机载波谱仪二维散射数据中提取出准高斯海浪斜率中全部参数,实现了波谱仪海浪二维斜率遥感。
[Abstract]:In the fields of meteorology, navigation, shipbuilding, ocean engineering and so on, high-precision real-time wave information is needed. Wave directional spectrum is an important wave information. The statistical characteristics of ocean wave field (wave height, wavelength, wave period, wave direction, wave steepness, etc.) can be obtained from the wave direction spectrum, so it is very important to obtain the wave direction spectrum. Wave spectrometer is a new type of microwave sensor specially designed for wave directional spectrum detection. It is a real aperture radar with a small incident angle of 360 掳azimuth rotation scanning. The world's first satellite carrier spectrometer (SWIM(Surface Wave Investigation and Monitoring) will be launched into orbit with the Chinese and French ocean stars in 2018. In this paper, the inversion of wave directional spectrum by using the measured data of the machine carrier spectrometer is studied. Aiming at the problem of large range of incident angle in airborne case, this paper first discusses the method of extracting modulated signal, and then, in view of the important influence of speckle noise on the inversion performance of wave spectrum, the formation mechanism of speckle noise on the sea surface of the spectrometer is studied emphatically. The statistical characteristics and removal methods, the inversion of the wave directional spectrum from the measured data of the wave spectrometer, and the comparison between the inversion results and the buoy data are carried out. Another main research content of this paper is to use wave spectrometer data to realize wave slope inversion. Wave slope is the basic physical parameter of the sea / air interface, but there is still a lack of direct measurement in a wide range. The special mode of operation of the wave spectrometer can obtain the two-dimensional scattering data of the sea surface changing with the incident angle and azimuth under the small incidence angle, which makes the remote sensing of the wave slope possible. Based on the quasi-mirror scattering approximation model, the wave slope inversion model of the wave spectrometer is established in this paper, and the simulation results of the wave slope inversion model are compared with those of the small-angle sea surface exact scattering model-physical optics model. The applicable range of incident angle of slope inversion model is determined. By means of nonlinear least square two-dimensional inversion method, all parameters of quasi Gao Si wave slope are extracted from the two-dimensional scattering data of the machine carrier spectrometer, and the remote sensing of the wave slope is realized.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：P716.22;P731.2

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