CEDAR: Vertical Velocity Measurements in the Mesosphere: Biases and Possible Solutions Using Spatial Interferometry

最重要的参数之一，可以导出 大气多普勒雷达，是垂直分量的 中性风 这个项目将比较和对比各种 用于估算中间层垂直速度的方法。 中间层-平流层-对流层（MST）和部分反射 漂移（PRD）雷达将用于实现这一目标。 MST雷达通常使用垂直指向波束， 速度-方位-显示（VAD）技术估计 垂直风 垂直波束技术可以通过以下方式偏置： 仪器和大气的影响。 PI建议， 使用空间干涉测量法可以消除任何仪器偏差 (SI)来追踪像天鹅座A这样的射电星星。 差异 天文位置和从SI获得的位置 测量结果可归因于光束中的系统偏移 位置 任何大气偏差，由于不均匀性， 反射率场，也可以使用SI技术去除。 如果 正确实施，VAD技术可以产生无偏的 垂直风的估计。 另一方面，如果不适当地 实施，由此产生的垂直速度估计将是 受到风场发散的影响 PI建议 使用中间和上部实现VAD和SI技术 (MU)日本Shigaraki的大气雷达，射程为60-90公里。 这两种中层测量基本上都可以进行 同步 大多数PRD测量仅限于垂直位置 因为典型系统的配置。 因此 对于垂直指向的MST雷达，上述偏差是 也适用于PRD系统。 此外，偏见应该是 由于这些系统使用的典型的宽波束宽度， 雷达 PRD雷达是多接收机系统，工作频率为2-3 MHz. 因此，本文提出了利用SI消除偏倚的方法 技术与MST的情况非常相似。 私家侦探会让 使用PRD雷达进行测量，该雷达计划安装 由克莱姆森的研究人员在格陵兰岛的Sondre Stromfjord 大学和科罗拉多大学。

One of the most important parameters, which can be derived from atmospheric Doppler radars, is the vertical component of the neutral wind. This project will compare and contrast the various methods used in estimating the vertical velocity in the mesosphere. Mesosphere-stratosphere-troposphere (MST) and partial reflection drifts (PRD) radars will be used to achieve this goal. MST radars typically use either a vertically pointing beam or the velocity-azimuth-display (VAD) technique to estimate the vertical wind. The vertical beam technique can be biased by instrumental as well as atmospheric effects. The PIs propose that any instrumental bias can be removed using spatial interferometry (SI) to track a radio star such as Cygnus A. Differences between the astronomical position and that obtained from the SI measurements can be attributed to a systematic offset in the beam position. Any atmospheric bias, due to inhomogeneities in the reflectivity field, can also be removed using SI techniques. If implemented properly, the VAD technique can produce an unbiased estimate of the vertical wind. On the other hand, if not properly implemented, the resulting vertical velocity estimates will be biased by the divergence in the wind field. The PIs propose to implement both the VAD and SI techniques using the Middle and Upper (MU) Atmosphere radar in Shigaraki, Japan, in the 60-90 km range. Both these mesospheric measurements can be conducted essentially simultaneously. Most PRD measurements are restricted to the vertical position because of the configuration of typical systems. Therefore, the biases mentioned above, for the vertically pointing MST radar, are also applicable for PRD systems. Furthermore, the biases should be enhanced because of the typically wide beamwidths used with these radars. PRD radars are multiple-receiver systems operating at 2-3 MHz. As a result, the methods of eliminating the biases using SI techniques are very similar to the MST case. The PIs will make measurements using a PRD radar, which is planned for installation in Sondre Stromfjord, Greenland, by researchers at Clemson University and the University of Colorado.