Studies of Plasma Structure in the Ionosphere Using Scintillation and Tomographic Techniques

我们提出利用层析成像技术和闪烁技术研究电离层等离子体结构。每一个都总结如下。1. 层析成像技术：我们过去几年的模拟研究，以及其他人的一些研究，已经证明了在几十公里到几百公里的水平尺度上成像电离层结构的潜力和能力。我们建议建立一个接收站网络，接收来自导航卫星NNSS的多普勒频移信号，利用层析成像技术对赤道电离层进行成像，以了解赤道异常区的动态。该项目的相关任务包括修复和修改捐赠的JMR大地测量TRANSIT接收器、开发基于低成本PC的数据采集系统、开发选定现场的接收器、数据管理和处理、进一步开发计算机算法和数据解释。2. 闪烁技术：这个项目是关于分析已经收集到的闪烁数据在地球物理利益的不同地点。其中一个台站（Spitzbergen, 77.00oN, 15.55o，地磁倾角73.43oN）是一个极尖台站。闪烁技术观测到的小结构可能与极光的存在、行星际磁场的结构、电磁遗漏等有关。在太平洋-亚洲地区收集了一个台站网的资料，分析了闪烁与电离层扰动的关系。在赤道，闪烁数据可以与雷达数据相关联，以研究电离层运动与电离层小结构的产生之间的关系。

We propose to investigate the ionospheric plasma structures using two techniques: tomographic technique and scintillation technique. Each is summarized in the following. 1. Tomographic technique: Our simulation studies over the past several years, as well as several studies by others, have demonstrated the potential and capability of imaging ionospheric structures of horizontal scales from tens of kilometers to hundreds of kilometers. We propose to set up a network of stations to receive Doppler shifted signals from the navigation satellites NNSS for the purpose of imaging the equatorial ionosphere using the tomographic technique to learn about the dynamics of the equatorial anomaly region. This project has associated tasks in repair and modification of donated JMR geodetic TRANSIT receivers, development of a low-cost PC based data acquisition system, development of receivers at selected field sites, data management and processing, further development of computer algorithm, and data interpretation. 2. Scintillation technique: This project is concerned with analyzing already collected scintillation data at various sites of geophysical interests. One station (Spitzbergen, 77.00oN, 15.55o, geomagnetic dip 73.43oN) is a polar cusp station. The small structures observed by the scintillation technique can be related to the presence of auroras, the configuration of the interplanetary magnetic field, electromagnetic omissions, etc. In the Pacific-Asia region data from a network of stations have been collected to analyze the relation of scintillation with the traveling ionospheric disturbances. At equator the scintillation data can be correlated with the radar data to investigate the relation between ionospheric motions and the production of small ionospheric structures.