摘要: | 中華衛星三號預計在民國94年春天發設升空,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星系。主要科學目的在於利用GPS(Global Positioning System)人造衛星訊號橫切穿過地球大氣時,因大氣折射指數作用所造成之訊號延遲,藉反演法可以得到大氣折射指數隨高度之分布,進而估算出大氣溫度,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(Triband 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資料,進行有關之電離層科學與應用研究。本計畫擬以整合型計畫方式提出,其中除了總計畫之外,包括五個子計畫,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,小型電離層光測器量測水平電子含量之研究,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 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. This project is an integrated one consisting of five sub-projects, including the retrieval and validation of COSMIC ionospheric electron density profile data, analysis of ionospheric global dynamics and study of space weather forecast, investigation of 4-dimensional ionospheric tomography, study of ionospheric irregularities and scintillation, and the measurements of horizontal variations of total electron content using TIP. We hope that the results of this integrated project could greatly improve he academic research level in the field of space science in Taiwan and create the capability of the forecast of space weather in ionosphere in the future. 研究期間:9012 ~ 9112 |