Simulation of ionospheric tomography by using global positioning system and low earth orbit satellites

• Main Authors: Yue-Cheng Lin, 林昱程
• Other Authors: Jann-Yenq Liu
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/22870869551795509103

碩士 === 國立中央大學 === 太空科學研究所 === 94 === The global positioning system (GPS) has been employed to calculate the total electron content (TEC) with advantages of its worldwide coverage and high time resolution. Recent developments on low earth orbit (LEO) satellites with the radio occultation (RO) technology, such as CHAMP , SAC-C, or FORMOSAT-3 COSMIC, provide the horizontal (tangent ray) observations to derive the vertical profiles. In this study, the two observations are combined to reach a new approach, the Multiplicative Algebra Reconstruction Technique (MART) is modified to reconstruct and obtain a high spacial resolution three-dimensional ionospheric electron density structure. The simulations indicate that the new approach significantly reduces the dependence of MART on initial values and achieves better reconstructions. Results show that observations from LEO satellites and/or priori information from co-located ionosondes can greatly improve the performance of inversion distributions.