近年來，商業化之立方衛星在全球太空產業迅速成長，這是由於立方衛星相比於大型衛星具有成本低、研發週期短與發射彈性高等優勢，能在限制功耗與體積的條件下執行多樣化任務，也適合透過星座形式部署大範圍通訊與監測系統。
在海事監管方面，陸地上之自動識別系統( AIS , Automatic Identification System）因地球曲率與天線高度受限，對遠洋船舶的即時覆蓋不足；若於低軌衛星搭載AIS接收酬載，可大幅延伸 AIS 監控範圍至公海。臺灣位處西太平洋航運樞紐，透過衛星接收 AIS 得以即時掌握周邊海域船舶動態，對航安管理、漁業資源保護與國土安全均具有相當大的價值。
本論文專注於立方衛星 AIS 訊號接收演算法之開發與驗證。首先，以系統模型分析都普勒效應與鏈路預算，並且評估天線場型與衛星姿態調整對接收 AIS訊號的影響，以尋求立方衛星之最佳配置。訊號接收演算法於 MATLAB 建立非相干之差分解調流程，採用最大似然序列估計解調方法強化低訊號雜訊比情況的接收效能，並利用衛星在軌蒐集之 AIS 訊號樣本進行演算法驗證，確認所提出接收機演算法在真實軌道環境下之有效性與可靠性。此外，亦針對所提出的衛星 AIS 訊號接收演算法進行硬體實作與優化，選用與在軌衛星相同的硬體平台 ADRV9361-Z7035，實現即時處理能力，除了於地面完成功能驗證，也實際進行台南安平港 AIS 訊號接收試驗，成功證明本論文提出之接收機演算法與硬體架構皆具備實務應用之效能與穩定性。綜上所述，本論文完成從演算法設計、硬體實作到實際資料驗證之完整流程，所提出之 AIS 接收技術不僅具備實用性與穩定性，亦具潛力應用於未來低軌衛星之海事監控任務。

In recent years, commercial CubeSats have rapidly grown in the global space industry. This is because CubeSats have several advantages over large satellites, including lower cost, shorter development time, and higher flexibility in launch. CubeSats can carry out a variety of missions under limitations in payload, power, and size. They are also suitable for building large-scale communication and monitoring systems through satellite constellations.
In maritime surveillance, shore-based Automatic Identification System (AIS) has limited real-time coverage of ocean-going ships due to the Earth's curvature and the height of ground antennas. If AIS receivers are placed on Low Earth Orbit (LEO) satellites, the monitoring range can be greatly extended to cover open seas. Taiwan is located in the West Pacific shipping hub, and using satellites to receive AIS signals helps monitor nearby sea areas in real time, which is valuable for maritime safety, fishery protection, and national security.
This thesis focuses on the development and verification of AIS signal receiving algorithms for CubeSats. First, a system model is used to analyze Doppler effects and the link budget. It also evaluates how antenna patterns and satellite attitude affect AIS signal reception, in order to find the best configuration for CubeSats. The receiving algorithm is built in MATLAB and uses a non-coherent differential demodulation process. An Maximum Likelihood Sequence Estimation (MLSE) demodulation method is applied to improve reception performance under low Signal-to-Noise Ratio (SNR ) real AIS signal data collected by satellites is used to verify the algorithm, proving its effectiveness and reliability under real orbital conditions.
In addition, the proposed satellite AIS receiving algorithm is implemented in hardware and optimized. The same hardware platform as the on-orbit satellite, ADRV9361-Z7035, is used to achieve real-time processing. The function is verified on the ground, and a real AIS signal reception test is performed at Anping Port in Tainan. The results successfully prove that both the proposed algorithm and hardware design are practical and stable for real applications.
In summary, this thesis completes a full workflow from algorithm design to hardware implementation and real data validation. The proposed AIS receiving technique is not only practical and stable, but also has great potential for future maritime monitoring missions using LEO satellites.

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