在民航的領域裡，當飛機進場降落時，有許多嚴格的導航規範，而陸基增強系統是由國際民航組織(International Civil Aviation Organization, ICAO) 所提出來的一項用來幫助飛機進場時能滿足這些規範的系統。
先前，我們已經建立了陸基增強系統原型並且曾在高雄國際機場實驗。我們將數個參考站以及一個靜態使用者架設在高雄國際機場的跑道周邊收集資料並且使用第一類精確進場的標準(Category I, CAT I) 來驗證陸基增強系統原型之性能，在我們收集的有限資料中沒有出現任何HMI (Hazardously Misleading Information, HMI)。於是在本研究中，我們將設備架設在台中國際機場周邊，並進行了飛測實驗來驗證陸基增強系統原型，這項試飛實驗是在陸基增強系統進場服務類別C (GBAS Approach Service Type C, GAST C) 標準下來進行，我們的三次試飛實驗從2019年10月24日開始，每一次的試飛實驗長達三小時左右。陸基增強系統主要是幫助飛機精確進場降落，因此我們的結果分析會著重在進場及降落的階段。在我們試飛實驗的結果並不符合第一類精確進場的標準，且有出現HMI，於是我們進行了更深入的分析，並推測發生HMI的原因。為了解決HMI的問題，我們提出了以高度計來輔助最小平方法。因為設備的限制，我們無法取得真實氣壓高度計資料，於是我們以RTK (Real Time Kinematic, RTK)所計算出來的高度當作外加高度。經過外加高度的輔助後，定位誤差減少且沒有發生任何HMI，本文中將針對陸基增強系統原型飛測提供詳細的分析與討論。

A ground based augmentation system (GBAS) is a system proposed by the International Civil Aviation Organization (ICAO) to meet the stringent navigation requirements of civil aviation. We had already developed a GBAS prototype and conducted a field test at Kaohsiung International Airport (ICAO code: RCKH). We installed reference stations and a static ground user near the runway at RCKH. The field test data was used to validate the performance of the GBAS prototype based on the required navigation performance (RNP) of a Category (CAT) I precision approach and landing. The result showed no hazardously misleading information (HMI) in the finite data we received. In this work, we installed the experimental reference receivers near Taichung International Airport (ICAO code: RCMQ) in Taiwan. Then, we conducted flight tests at the airport and evaluated the navigation performance of the GBAS prototype. The experiment was conducted to validate the GBAS performance based on the GBAS approach service type (GAST) C specifications. There were three flight tests in the experiments. The first flight test was carried out on October 24th, 2019. Each flight test took approximately three hours. We focused our analyses on the approach phase since the GBAS is aimed toward supporting precision approaches and landings. The results of this validation showed that an HMI event occurred, and based on the flight test data, the performance of the GBAS prototype appeared to fail to meet the CAT I requirement. We confirmed that the HMI event was not caused by the GBAS prototype algorithm, truth, ionosphere, and troposphere. Then, we provide a method to resolve the HMI event, a barometric altimeter-aided least squares (LS) method. Since we couldn’t obtain the barometric altitude, we used the altitude calculated using real-time kinematic (RTK) positioning as the external altitude. The position error was decreased significantly after the baro-aided LS, and the HMI event was absent. A detailed analysis of the resulting navigation capabilities is carried out in this thesis.

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