本研究計畫主要的研究重點為東亞中低緯電離層之小尺度結構及動態研究。我們首先建立新的低緯電離層電腦斷層網站 New LITN (New Low-Latitude Ionospheric Tomography Network)，結合日本電離層電腦斷層網站，形成一中低緯電離層電腦斷層網，收集Naval Navigation Satellite System(NNSS)衛星的斜向相對全電子含量(STEC)資料。其次收集東亞中低緯及附近地區的全球定位系統(GPS)網站上空的垂直絕對全電子含量(VTEC)，結合兩者可得NNSS、GPS 至接收站的絕對全電子含量(TEC)。最後再建立一套疊代或非疊代演算法，根據前述所測得的TEC 資料，反演求得東亞上空中低緯電離層之電子密度分布，並對其結果，主要為赤道異常現象，做可能的物理解釋。The main purpose of this program is to study the structure of the middle and low latitude ionosphere in Eastern-Asia sector. We have set up a New Low Latitude Ionospheric Tomography Network (LITN) along the 120 degree geolatitude. The New LITN will join Japan beacon receiver to receive transit satellite beacon signals and measure relative slant total electron content (STEC) values. We then collected absolute vertical TEC data from the Global Positioning System (GPS) network near Taiwan. Combining the relative STEC and VTEC data sets we can get the absolute STEC. Finally, we shall develop an algorithm to reconstruct the electron density distribution in the low latitude ionosphere in the Eastern-Asia sector based on the observed absolute TEC data from NNSS and GPS. Physical explanation on our results will also be discussed, especially on the Equatorial Anomaly Region (EAR). 研究期間：9808 ~ 9907
