利用無人機作為數據收集的方法，是近來在許多實際場景中，具有前景和新穎的應用。本文研究無人機在物聯網網路中，信息新鮮度(Freshness)相關的數據收集問題。最近新鮮信息的實時(Real-time)傳輸，已成為一個重要的研究議題。信息年齡(Age of Information, AoI)被定義為無人機的飛行時間加上離開該傳感器節點後的數據上傳時間。在我們的問題中，無人機從事數據收集的任務，從來源數據中心收集感測器數據到目標數據中心。經由考慮軌跡規劃、信息年齡和總完成時間，我們提出了一種三階段演算法來最小化無人機輔助物聯網網絡中任務的平均信息年齡。實驗結果證明我們的效能優於其他演算法。

The use of unmanned aerial vehicles (UAVs) to collect data is a recent promising and novel application in many practical scenarios. This paper studies the data collection problem related to how fresh the information is in the UAV-assisted IoT networks. The real-time transmission of fresh data has been an increasingly crucial topic recently. The Age of Information (AoI) is defined as the flight time of the UAV plus the data uploading time after leaving this sensor node. In our problem, UAV is assigned the mission of data gathering to collect real-time data from the source data center to the destination data center by considering the trajectory planning, information age, and the total completion time. We proposed a three-phase algorithm to minimize the average AoI of the mission in UAV-assisted IoT networks. Simulation results show that our performance outperforms the baselines.

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