| 摘要: | 中華衛星三號預計在民國94年秋天發設升空，將六顆小衛星佈放到高度為約800公里的軌道上，形成一個繞地運行的人造衛星星系。主要科學目的在於利用這些小衛星上所配置的全球定位系統(Global Positioning System, GPS)人造衛星訊號接收機﹐將接收所得的GPS訊號，藉電波掩星技術(Radio Occultation Technique)所反演出的大氣折射指數(Atmospheric Refractive Index)隨高度之分布，再推算出的大氣溫度，水汽含量，以及電離層電子密度等參數隨高度之全球分布，進行有關低層大氣之天氣預報與氣候研究，以及電離層之全球動態研究。故中華衛星三號計畫又稱COSMIC(Constellation Observing System for Meteorology, Ionosphere and Climate)衛星計畫。每一顆COSMIC衛星將具有三個科學酬載，除了前述之GPS訊號接收機之外，尚有三頻標識訊號(Tri-band Beacon Signal)發射機以及小型電離層光測器(Tiny Ionospheric Photometer)。前者可以量測電離層全電子含量以及閃爍現象，後者則可以觀測衛星垂直下方之全電子含量。本計畫將利用COSMIC衛星計畫中所獲得之電離層電子密度之全球分布，以及全電子含量和閃爍(Scintillation)資料，進行有關之電離層科學與應用研究。在本年度的電離層研究整合計畫中，除了總計畫之外，包括四個子計畫，分別為ＣＯＳＭＩＣ電離層資料之反演與驗證，電離層全球動態研究與太空氣象之預報研究，電離層斷層掃描之研究，以及電離層不規則體與電離層閃爍之研究。本整合計畫之最終目標，在於建立我國特有之電離層模式，能夠進行電離層全球動態分析與太空氣象之預報，完成COSMIC電離層資料之反演與驗證方法，提高COSMIC資料的精確度與可用性，並發展出四維電離層斷層掃描技術，以進一步了解電離層電子密度在大尺度三度空間中的動態變化，以及建立電離層小尺度不規則體與人造衛星訊號閃爍現象之關係。本計畫之執行成果，相信對於提升我國太空科學之研究學術水準以及發展未來太空天氣預報之能力與相關應用，將有極為重大之助益。 ROCSAT-3, which is a satellite constellation system consisting of 6 small satellites being planning to be deployed in the orbit at around 800 km height, is scheduled to launch in 2005. The ROCSAT-3 project is also called COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate) project. There are three payloads mounted on each ROCSAT-3 satellite, namely, GPS receiver, tiny ionospheric photometer (TIP), and tri-band beacon transmitter. With the GPS receiver, the atmospheric refractive index can be retrieved from received GPS signals using limb sounding technique, in which the profiles of temperature and ionospheric electron density can be deduced. With TIP, the horizontal variation of ionospheric total electron density content can be observed. The ionospheric scintillation and total electron density content can be measured by using tri-band beacon transmitter. In this proposal, we are going to employ the above mentioned satellite instruments in combination with ground-based ionospheric instruments to study the structures and dynamics of ionosphere. During the fiscal year 2003, the ionospheric research of the COSMIC project will be conducted parallelly by five individual projects, including management project, development of new algorithm for the retrieval and validation of COSMIC ionospheric electron density profile, model study of ionospheric global dynamics and space weather forecast, investigation of 4-dimensional ionospheric tomography, and study of ionospheric irregularities and scintillation using tri-band beacon signals combined with ground-based radar. We hope that the results of this integrated project for the ionopsheric research could not only greatly improve our understandings of the ionosphere and advance the academic research level in the field of space science in Taiwan, but also create the capability of the forecast of space weather in ionosphere in the future. 研究期間：9201 ~ 9212 |
