精密單點定位（PPP）是一個高精度的全球導航衛星系統（GNSS）定位技術，藉由單個接收器以及精密衛星軌道、精密衛星鐘差和其他誤差改正產品，消除定位誤差使其達到公分等級定位精度，然而較長的收斂時間大大限制了其應用。研究指出，使用電離層模型作為約制條件處理PPP時，能夠有效提升定位效能。然而在太陽活動活躍期時，電離層資訊的精確度及時空解析度可能會嚴重影響精密單點定位的效能。全球電離層模型在該時期對於低緯度地區的使用來說可能幫助有限，因此凸顯了區域電離層模型能夠提供更即時、更精確的電離層資訊的價值。內政部國土測繪中心使用Trimble pivot軟體，根據台灣的衛星基準站，產生區域電離層模型，作為電離層資訊提供給使用者，幫助其定位解算。本研究利用上述的區域電離層模型，藉由時間內插及空間內插得到待測站對應的垂直總電子含量(VTEC)和穿刺點座標，再藉由映射函數轉換為電離層延遲，作為PPP解算的約制條件。研究結果發現，相較於傳統PPP模型，區域電離層模型在定位解算前30分鐘，能夠較明顯的提升定位精度，在10分鐘、20分鐘、30分鐘時，水平方向分別提升了20%、16%和13%；垂直方向則在20分鐘和30分鐘時分別提升15%和9%。收斂時間方面，以30公分作為收斂門檻值，水平方向減少41%，垂直方向沒有幫助；以20公分作為收斂門檻值，水平方向減少29%，垂直方向沒有幫助；以10公分作為收斂門檻值，水平方向減少3%，垂直方向減少11%。研究同時加入了使用全球電離層模型的結果，兩者比較可以發現，區域電離層模型能夠更加顯著的提升精密單點定位效能，特別是在水平方向，本研究顯示了在太陽活動活躍期時，區域電離層模型對於精密單點定位的重要性。

Precise Point Positioning (PPP) is a Global Navigation Satellite System (GNSS) positioning technique that uses a single receiver, along with precise satellite orbits, satellite clock corrections, and other error correction products, to eliminate positioning errors and achieve centimeter-level accuracy. However, the long convergence time significantly limits its application. Studies have indicated that using external ionospheric information as constraints in PPP processing can effectively improve positioning performance .The National Land Surveying and Mapping Center (NLSC) of Taiwan employs Trimble Pivot software and has established reference stations across Taiwan to generate regional ionosphere maps. These maps provide ionospheric information to users, assisting in positioning solutions. This study utilizes the aforementioned regional ionosphere maps, employing temporal and spatial interpolation to obtain the corresponding Vertical Total Electron Content (VTEC) and pierce point coordinates for the test stations. The VTEC is then converted into ionospheric delay using mapping functions, which serves as a constraint in PPP solutions.

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