中文摘要：

由三维射线追踪微分方程推出掩星三维直角坐标射线追踪的矩阵方程,对实现射线追踪的具体步骤进行讨论。采用Ne Quick作背景模拟夜间和白天的掩星电离层三频载波相位延迟观测数据,采用双频绝对TEC反演法对白天模拟数据进行反演,并比较3种不同频率组合对反演结果的影响。结果表明,在附加相位延迟等精度观测条件下,L1-L5组合获得的反演结果与模式值最为吻合。

英文摘要：

GNSS radio occultation technique has been proved to be an important method to investigate the iono- spheric electron density in different levels. 3D ray tracing is the best choice for analyzing the propagation of ray in i- onosphere. A group of matrix equations from the differential equation in Cartesian coordinate was used to analyze the detail steps of ray tracing with the formulas. The NeQuick model is used to simulate the excess phase of L1, L2 and L5, and the simulated results are used to retrieval the electric density profile with absolute TEC inversion method with different band combination. The result of two numerical preferable choice for vertical density profiles inversion under experiments shows that the combination L1-L5 is the the identical observation conditions.