本篇論文是使用福爾摩沙衛星三號ionPhs(Level1)的資料進行GPS掩星法的計算，可反演出電離層之電子濃度；其演算方式是參考[Antonio Rius, 1997]論文中所提到的方式，由ionPhs中超額相位和衛星的位置和速度的資料可算出偏折角(bending angle)，再利用Abel transform積分法算出折射指數(index of refractivity)，進而算出電離層之電子濃度(Electron density)。最後，將會比較和討論COSMIC之反演法與[Antonio Rius, 1997]論文中其反演法之差異，再跟福衛三號ionPrf(Level2)之電子濃度做交叉比對，並且討論及誤差之分析。結果與討論之重點會放在模擬的部份，希望可以透過模擬的方式，進一步探討GPS掩星反演法演算之準確性，且可以確認[Antonio Rius, 1997]論文中之反演法和計算過程的誤差值，再分別討論其結果。 The ionospheric electron density profile can be retrieved from total electron content (TEC) by using Abel method, which is measured by LEO satellite from GPS signal. However, the excess phase information of GPS signals received by COSMIC satellites can also used to retrieve electron density profile in accordant with radio occultation technique, in which the bending angle of GPS is calculated and the ionosphere refractive index is converted using the Abel transform that contains electron density information. In this presentation, the electron density profiles obtained by piercing method and bending angle of GPS ray are compared and the discrepancies in the two are discussed.
