陸基增強系統(Ground Based Augmentation System, GBAS)能幫助飛具使用GPS(Global Positioning System)進行精確進場(precision approach, PA)與降落的系統，而IMT(Integrity Monitoring Test-bed)計畫的目的就是為了於台北飛航情報區(Taipei Flight Information Region, Taipei FIR)內建置陸基增強系統地面設施原型機，IMT計畫主要又分為兩個部份，第一個目的是評估IMT主控站演算法對導航效能的影響，第二個目的是驗證IMT使用者演算法對導航效能的影響，其中第二個目的主要工作包括了發展GBAS使用者接收機平台。本論文分別提出以軟體無線電(Software Defined Radio, SDR)與FPGA(field-programmable gate array)技術實現GBAS使用者接收機平台，其主要與一般的硬體接收機之不同，GBAS使用者接收機平台可以根據需求修改其基頻處理器與通用處理器，另外由於GBAS使用者接收機平台需要處理GPS訊號與IMT服務訊息，所以本文也將介紹GPS的基頻處理器與通用處理器的原理，當中包括處理器的硬體架構與軟體流程，除此之外，GBAS使用者演算法實現在GBAS使用者接收機平台的過程將會呈現，要注意到GBAS使用者是根據RTCA DO-253C發展而成，而在本文會介紹差分修正量應用流程、接收機位置計算流程與保護極限計算流程。目前GBAS使用者接收機平台已經可以成功地應用IMT服務訊息計算出接收機位置與保護極限(Protection Level, PL)。事實上IMT是以支援第一類精確進場而發展，所以GBAS接收機測試平台在應用IMT服務訊息後是以第一類精確進場的需求為驗證標準。為了驗證GBAS接收機雛型的效能，一些場地測試分別在高雄國際機場與屏東賽嘉飛行場舉行，在高雄國際機場的實驗中，GBAS接收機測試平台以靜態的方式測試並驗證導航效能，在屏東賽嘉飛行場的實驗中，GBAS接收機測試平台則是安裝在輕航機上以動態的方式驗證結果。

Aircrafts can conduct the GPS-based precision approach (PA) and landing by Ground Based Augmentation System (GBAS). IMT (Integrity Monitoring Test-bed) is aimed to establish GBAS ground facility prototype in Taipei Flight Information Region (FIR). The IMT project is divided into two parts. The first part is to assess the effects on navigation performance due to various parameter changes in the algorithms of GBAS master station, and the second part is to evaluate the impacts on navigation performance from the changes in the GBAS user algorithm. This involved developing a GBAS test-bed user receiver prototype. The Software Defined Radio (SDR) and field-programmable gate array (FPGA) technology are used to implement a GBAS receiver prototype. Unlike a conventional hardware-based receiver, the GBAS receiver prototype allows us to modify the baseband processor and general purpose processor. In addition, because the GBAS receiver prototype needs to process the GPS signal and IMT messages, the theory of the baseband processor and general purpose processor are briefly introduced. Also, this work shows the hardware architecture of the baseband processor and the flowchart of the general purpose processing. The implementation of GBAS user algorithm on the GBAS receiver prototype is presented as well. Of note, the GBAS user algorithm is based on RTCA-DO253C ,and the GBAS user algorithm includes application of differential corrections, the calculation of position solutions, and the computation of protection level (PL). Current GBAS receiver prototype can apply the IMT correction messages and output differential position solution and PL. After applying the IMT correction messages, the performance of GBAS receiver prototype is aimed to meet the requirement of CAT I. In order to evaluate the performance of GBAS receiver prototype, several field tests were conducted at Kaohsiung International Airport (ICAO code: RCKH) and Sijjia air field. In RCKH experiment, the performance of GBAS receiver prototype was tuned and verified as a static user. In Sijjia air field experiment, the GBAS receiver prototype was deployed on the ultralight vehicle as a dynamic user.

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