傳統的船舶自動識別系統(AIS)受到陸上設施的可視範圍限制，導致無法監控廣大的離岸海洋區域，此限制不利於在這些區域作業船舶的航海安全和氣象預報。為了解決這個問題，我們提出了一種利用低地球軌道(LEO)立方衛星的星載船舶自動識別系統(S-AIS)進行實時氣象報告的系統。我們的系統使用基於現場可程式化邏輯陣列(FPGA)的微型軟體定義無線電(MSDR)作為AIS收發機。船舶可以自動收集氣象資料並嵌入AIS訊息中，這些AIS信號會通過裝載S-AIS的立方衛星轉發到地面站，從而擴展AIS的覆盖範圍並提供有價值的實時海上氣象資料，以提高海上安全和氣象預報的準確性。我們基於FPGA的S-AIS收發機具有高度的靈活性和性能，能夠有效地傳輸和接收嵌入氣象資料地AIS信號。這個多用途的技術可以在衛星上作為AIS中繼站，也可以在船舶上和地面站中作為AIS 收發機，從而進一步增強通信網路的連結與數據的收集。此外，我們還設計並分析了足以滿足任務需求的LEO衛星軌道，軌道設計選擇使用GRT軌道，在500公里高的衛星軌道與70度的FOV考量下，衛星可以提供半徑350公里的圓的資料收集面積，在10顆衛星的星系設計下可以提供約40分鐘的資料更新率。;Traditional Automatic Identification System (AIS) relies by terrestrial infrastructure, leaving vast ocean areas unmonitored. This limitation restricts maritime safety and weather forecasting for vessels operating in these regions. This study proposes a novel approach utilizing Satellite Automatic Identification System (S-AIS) onboard Low-Earth Orbit (LEO) CubeSats for real-time weather reporting. Our system uses Miniature Software-Defined Radios (MSDRs) built on Field-Programmable Gate Arrays (FPGAs) for efficient and customizable AIS transceivers. The flexibility of FPGA-based S-AIS transceivers facilitates rapid development and configuration of weather data reporting across the open water. Fishing vessels equipped with these MSDRs autonomously collect weather data and embed it within their AIS messages. S-AIS equipped CubeSats can then relay these enhanced AIS messages to ground stations, significantly extending the AIS coverage and providing real-time weather data for improved maritime safety and weather forecasting accuracy. This multipurpose technology functions as an AIS repeater on CubeSats and an AIS transceiver on vessels or ground stations, enhancing network connectivity and data acquisition. Additionally, the study explores the design and analysis of potential Repeating Ground Track (RGT) orbits for Low Earth Orbit (LEO) satellite to provide weather-reporting S-AIS service coverage area of a circle with a radius of 350 km with 70 degrees Field of View (FOV) at altitude of 500 km. For the 10-satellite constellation configuration, this constellation can provide data update frequency up to 40 minutes.
