目前美國的GPS衛星定位系統已經相當成熟也被廣泛應用於各種工業和商業儀器提供位置、導航和時間 (PNT)資訊。而歐盟 (EU)發展的衛星系統「伽利略」 (Galileo)，也分別於2005和2008年發射了兩顆測試衛星GIOVE-A與GIVOE-B。此系統預計在2011-2013完成佈建30顆衛星的星系，加上美國的GPS系統，全球將會有60顆以上的導航衛星能提供PNT服務。導航衛星數量的大幅提昇以及星系分佈的優化能夠保證導航時失去一枚衛星對使用者也不會有明顯之差別，更可以提供較精準的位置和發展更多應用。本論文主旨即為實現Galileo/GPS雙模接收器，本接收器將能夠接收L1頻帶內所有的Galileo和GPS衛星系統的民用訊號，並利用導航資料解算出使用者位置。論文中介紹接收器整體的架構以及硬體、韌體和軟體實現的詳細說明，並接收GPS和Galileo測試衛星之訊號來做測試和驗證結果。

The GPS of US have been widely used in many industrial and commercial sectors to provide position, navigation and timing (PNT) information. The Galileo satellite system developed by the EU have already launched two testing satellite, GIOVE-A and GIOVE-B in 2005 and 2008, respectively. The system which consists of 30 satellites is planned to be fully operational during 2011-2013. Thus, in the future when both GPS and Galileo are deployed, there will be more than 60 navigation satellites providing PNT service. The large number of satellites together with the optimization of the constellation will ensure that the loss of one satellite has no discernible effect on the user, and providing even more accurate position and develop more application. This thesis presents an implementation of a Galileo/GPS dual-mode receiver. The receiver is required to receive all the civilian signals of the Galileo and GPS satellite systems in the L1 band, and calculate user’s position by using navigation data. The thesis describes the overall receiver architecture, the detailed implementation in hardware, firmware, and software, and the test results using GPS and Galileo test satellites.

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