隨著衛星定位的技術漸趨成熟，GPS定位已普遍運用在日常生活中。而在GPS相關應用愈趨重要的同時，其相應的欺騙訊號技術也隨之進步，因此GPS訊號的驗證工作日漸受到重視。本論文首先會著眼於發展一訊號認證機制，此架構實現於兩台軟體無線電接收機。此外經由改良已存在之方法，本研究使用相較於現存方法更具彈性的方式進行訊號認證。此認證機制不僅可降低接收時的取樣率且不需強制要求兩台接收機之取樣率相同，還可大幅降低處理訊號時需儲存的資料量。另外在訊號認證的實際應用上，發出警告與定位結果真正受到影響程度的取捨是很重要的課題，為了進一步降低誤判的情況發生，本論文而後會藉由模擬接收機受到欺騙訊號攻擊的狀況的實驗來探討GPS訊號受干擾程度與定位結果的關係，並以提出的訊號認證演算法排除欺騙訊號的攻擊，使定位結果更加可靠。

Nowadays, satellite navigation techniques have been widely applied in our daily lives. At the same time, spoofing attacks toward satellite navigation have also been advanced. Therefore, the authentication of satellite navigation signals is of importance. The thesis focuses on developing a mechanism of GPS (Global Position System) signal authentication. This mechanism uses two software-defined radio receivers and improve the existing methods. In fact, this method is more flexible than the existing ones. The following are the advantages of this mechanism: (1) it can reduce the sampling rate while receiving GPS signals; (2) two receivers would not be required to have identical sampling rate; and (3) it significantly reduces the amount of data to be stored during signal processing. Furthermore, in the practical application of signal authentication, there is a trade-off between warning and the influence level on GPS positioning. To decrease the probability of false alarm, this study simulates the situation that the receiver is cheated; these experiments investigate the relationship between the influence level of GPS signals and the positioning results. By using the proposed signal authentication algorithm, the positioning results become more reliable.

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