单多普勒雷达风场反演（VAD）技术的研究

【作者】 李杰；

【导师】 顾松山；

【作者基本信息】 南京气象学院 ， 大气物理学与大气环境， 2004， 硕士

【摘要】 多普勒雷达资料的应用，关键之一在于发展风场反演技术。因为多普勒雷达探测到的仅仅是风矢量在径向上的分量。多普勒雷达探测到的径向风场资料必须通过一定的数学方法手段才能得到可用的二维、三维风场。 本文第一章概述了多普勒雷达的应用，分析了各种多普勒雷达风场反演技术并对风场反演技术进行总结和展望。第二章详细介绍了多普勒雷达资料的预处理方法。统计结果表明经过预处理后能较好的减少RMS。第三章在几种VAD算法中选择了一种较好的算法，分别用实际业务中使用的两种实施策略：单仰角VAD方法和多仰角VAD方法进行风场反演，比较了这两种算法的反演结果，并提出了融合这两种方法优点的自适应仰角取样策略。结果表明本文提出的自适应VAD方法结合了前两种VAD方法的优点，能得到更实用的结果。 由于VAD方法只是揭示了平均风矢量从低空到高空的演变，得到的是各个高度层上的平均风场，无法得知各个高度层上的水平风场。在一定的假设条件下，通过VAP或UW技术等其它方法反演获取二维风场。本文第四章中运用UW方法进行二维风场的个例反演试验。结果表明UW方法能反演出各高度层上部分二维风场信息。更多还原

【Abstract】 The key development of the wind retrieval technique is the application of Doppler radar data. A Doppler radar only measures the component of the velocity in the line of sight, the so-called radial velocity. Radial velocity data is not straightforward to interpret, some further processing is required before it can be presented to users. And structure of the wind field which we obtained with Doppler radar is not the real wind field; it should be converted into two or three-dimension wind field through some methods.Chapter one in this paper gives brief applications of Doppler radar, analyses the techniques of wind retrieval; The Second part introduce the methods of Dealiasing; Using VAD technique, the environmental wind can be extracted. During actual operation, there are two kinds of practice strategies, one is single-elevation VAD method, and the other is multi-elevation VAD method. There are different between those two methods. Self-adjust elevation VAD methods proposed combine the merits of front two methods. Those methods are discussed in the third part to find out the different, and self-adjust elevation VAD methods can get more valuable wind information.The changes of mean wind from low-level to high-level can be show from VAD technique. We can get the mean wind of certain level only, but no the distributing at different azimuth .So we maybe ignored some local -system. If we want to know the distribution of wind, we could use Velocity Azimuth Processing (VAP) method or Uniform Wind (UW) technique etc. to get the two-dimensional wind field. Finally experimentation to retrieval two-dimensional wind field using UW technique was carried out It is showed mat wind character can be extracted through this method更多还原