GPS地面台网和掩星观测结合的时变三维电离层层析

本文给出GPS地面台网和掩星观测结合的时变三维电离层层析的原理、算法和基于实测数据的反演结果.反演结果的比较表明，联合地基GPS与掩星观测数据进行重建，电子密度整体图像的重建质量特别是其垂直结构的重建质量得到了明显改善.在平静日和磁暴期间两种条件下利用实测数据的重建结果表明，GPS地面台网和掩星观测结合的电离层层析可以获得电离层电子密度在高度-纬度-经度-时间四维空间中的变化.重建结果清晰地显示了磁暴期间电离层负相暴效应，表明结合GPS地面台网和掩星观测的时变三维电离层层析可以有效地监测扰动条件下的大尺度电离层结构.

Time-dependent 3-D computerized ionospheric tomography with ground-based GPS network and occultation observations

This paper illuminates the principle and algorithm of time-dependent three-dimensional Computerized Ionospheric Tomography with ground-based GPS network and occultation observations as well as reconstruction results based on real measurements. A comparison of reconstruction results shows that the whole quality of reconstructed electron density image, specially the vertical resolution of electron density structure, is obviously improved by the combination of ground-based GPS beacon measurements with GPS occultation observations. Reconstructed results based on actual observations under conditions of geomagnetic quiet and storm both show that variations of ionospheric electron density with height, latitude, longitude and time can be resolved by means of CIT with ground-based GPS network and occultation observations. Ionospheric negative phase storm effects are exhibited in the reconstruction results during the magnetic storm. The study of present paper confirms that (time-dependent) 3-D CIT with ground-based GPS network and occultation observations is a powerful tool to monitor large-scale ionospheric structures under disturbed conditions.