全球衛星導航系統是下一代的民航監視系統的關建促成技術，其所能提供連續、準確的定位服務使得此套系統所衍生的民航監視系統能夠迎合快速發展的民航運輸流量。然而，許多研究亦指出衛星導航訊號可以被刻意或非刻意的干擾。為了應付衛星導航系統無法正常運作的狀況，替代導航系統的概念在許多研究中被提出，其主旨即為如何在全球衛星導航系統失效時對空域中的航機持續提供相同精準度的導航服務。
在這篇論文的第一部分使用市面上即可取得的器材實現了廣域多點定位架構的替代導航系統，並以此套系統以及抵達時間差定位演算法於台南市周邊進行了一個城市規模的航機定位實驗。此篇論文所取得的定位結果驗證了廣域多點定位架構的可行性並以百公尺等級的誤差定位出台南上空的航機，並且這個實驗同時也展示了廣域多點定位架構先天上受制於參考站幾何分布的特性。
因此，在這篇論文的第二部分對參考站幾何限制著手討論。海島型國家如台灣由於先天上地形的條件，在使用域多點定位架構下需要更加注意並考量此一限制。多觀測量定位演算法在本論文的第二部分被討論以增進廣域多點定位架構在參考站分布相對受到限制時的表現，其結果顯示本論文所提出的新一代廣域多點定位增強系統架構能夠對在台北飛航情報區單一參考站涵蓋範圍增進約10%的定位服務範圍。

Global navigation satellite system (GNSS) is essential to aviation communication, navigation, surveillance, and air traffic management. A continuous accurate positioning service allows a GNSS-supported surveillance system to keep up with the growing requirements of civil aviation. However, many studies have shown that GNSS signals are susceptible to interference. To continue accurate positioning service in the case of GNSS failure, various alternative positioning, navigation, and timing (APNT) systems have been proposed. The objectives of APNT systems are to provide navigation and surveillance services to ensure flight safety when GNSS fails.

In the first part of this thesis, the wide area multilateration (WAM) mechanism for APNT systems is developed using commercial off-the-shelf components, and a city-size multilateration experiment is carried out in the proximity of Tainan, Taiwan. Using the four ground reference stations surrounding Tainan, the differential time of arrival positioning algorithm is employed to calculate the positions of aircraft passing above Tainan. The positioning results show positive positioning result with positioning error around 100 meters horizontally. However, this experiment also showed the mechanism’s limitation on the positioning due to the geometry of stations.
In the second part of this thesis, to overcome the geometry limitation, a viable concept is developed based on a multi-measurement positioning algorithm. A simulation is conducted to validate the proposed concept. In comparison to the original WAM based APNT, the results showed that the positioning service coverage is increased about 10% using multi-measurement positioning algorithm.

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