Development of a data processing and distribution system for total electron content data of a GPS receiver network

对大气湍流及其结构的了解在很大程度上取决于观测技术。法国有一个小组正在进行无线电探空实验，以10厘米的超高分辨率测量大气温度廓线。另一方面，利用MU雷达，我们可以进行频域干涉(FDI)实验，以比通常更高的分辨率测量大气反射/散射回波的结构。这些日本和法国小组之间的合作实验，例如MUTSI(MU雷达、温度表和干涉测量)，是在这笔科学研究赠款的帮助下计划和实现的。以下是我们在这项拨款下进行的研究1.MUTSI实验：2000年5月，我们成功地进行了MUTSI实验，在MU雷达FDI和多波束实验的同时，发射了法国无线电探空仪和超高分辨率温度传感器。总共有10个俄罗斯探空器从京都的京田部发射，而我们可以估计它们在志贺市茂名的MU雷达附近的较近轨迹。数据分析：MUTSI实验的MU雷达数据由日本小组分析，无线电探空仪数据由法国科学家分析。经过几次数据比对，我们发现了许多厚度在10m或更小的很薄的湍流层，在其上方和下方的稳定区中存在不稳定区。进一步的雷达实验：在MUTSI实验结果的基础上，我们进一步用MU雷达进行了新的多波束实验，发现了一个有趣的特征，即回波强度的方位(水平)不均匀方向与风切变方向有很好的相关性。利用赤道大气雷达研究了回波强度与大气湍流的关系。

Understanding of the atmospheric turbulence and its structure largely depends on observation techniques. There is a French group that conducts radiosonde experiment to measure atmospheric temperature profile with the ultra-high resolution of 10 cm. On the other hand, with the MU radar we can conduct the Frequency Domain Interferometry (FDI) experiment to measure structure of the atmospheric reflection/scattering echoes with much higher resolution than usual. Cooperative experiment between these Japanese and French groups, e.g., MUTSI (MU radar, Temperature Sheets and Interferometry) was planned and realized with the help of this grant-in-aid for scientific research. Following is the list of studies we conducted under this grant.1. MUTSI experiment : In May 2000, we successfully conducted the MUTSI experiment by launching French radiosonde with ultra-high resolution temperature sensors simultaneously with the MU radar FDI and multi-beam experiment. Totally ten rasiosondes were launched from Kyotanabe, Kyoto while we could estimate their closer trajectory near the MU radar in Shigaraki, Shiga.2. Data analysis : The MU radar data from the MUTSI experiment were analyzed by the Japanese group while the radiosonde data were analyzed by the French scientists. After some meetings for the data comparisons we found many very-thin turbulence layers with 10 m or less thickness, in which unstable region exists within stable regions above and below them.3. Further radar experiment : Based on the results from the MUTSI experiment, we further conducted new multi-beam experiment with the MU radar, and found an interesting feature that direction of the azimuthal (horizontal) inhomogeneity of the echo intensity is well correlated with the wind shear direction. We also used the Equatorial Atmosphere Radar to study relationship between echo intensity and the atmospheric turbulence.