Iterative Trajectory Planning and Resource Allocation for UAV-Assisted Emergency Communication with User Dynamics  
[PERSON]  
1 School of Electronics and Information Engineering, Beihang University, Beijing 100083, China; [EMAIL_ADDRESS] (Z.Z.); [EMAIL_ADDRESS] (H.Z.); [EMAIL_ADDRESS] (X.Z.) Institute of Unmanned System, Beihang University, Beijing 100083, China; [EMAIL_ADDRESS] 1  
[PERSON]  
2 Institute of Unmanned System, Beihang University, Beijing 100083, China; [EMAIL_ADDRESS] 2  
[PERSON]  
3 School of Computer and Artificial Intelligence, Zhengzhou University, Zhengzhou 450001, China; [EMAIL_ADDRESS] 3  
[PERSON]  
1 School of Electronics and Information Engineering, Beihang University, Beijing 100083, China; [EMAIL_ADDRESS] (H.Z.); [EMAIL_ADDRESS] (X.Z.) Institute of Unmanned System, Beihang University, Beijing 100083, China; [EMAIL_ADDRESS] 1  
[PERSON]  
1 School of Electronics and Information Engineering, Beihang University, Beijing 100083, China; [EMAIL_ADDRESS] (H.Z.); [EMAIL_ADDRESS] (X.Z.) Institute of Unmanned System, Beihang University, Beijing 100083, China; [EMAIL_ADDRESS] 1  
[PERSON]  
1 School of Electronics and Information Engineering, Beihang University, Beijing 100083, China; [EMAIL_ADDRESS] (X.Z.) Institute of Unmanned System, Beihang University, Beijing 100083, China; [EMAIL_ADDRESS] (X.Z.) Institute of Unmanned System, Beihang University, Beijing 100083, China; ding@buaa.  
In recent years, the integration of UAVs into emergency communication systems has caught significant attention due to their ability to overcome limitations in traditional ground base stations [14]. In emergency-stricken cases, disasters such as earthquakes, hurricanes, and wildfires can inflict severe damage on ground communication infrastructure, making them either disabled or inaccessible. Consequently, timely and reliable communication services in such contexts play a vital role in rescue and response. Both civil and military institutions can benefit from UAV-assistance communication. Emergency response agencies like FEMA (Federal Emergency Management Agency) would be interested in leveraging UAVs to enhance communication capabilities during disasters or emergencies, while telecommunication companies could benefit from UAV-assisted communication planning algorithms to improve their capacity for assisting in affected areas. During the 2021 Henan flood, China Mobile dispatched Yilong drones to temporarily restore communication in the disaster area. UAV-assisted mobile communication has several advantages over traditional terrestrial or satellite-based communication systems, such as flexibility, mobility, scalability, ease of deployment, and low cost, therefore they can match the requirements needed in emergency communication cases.  
However, the field also encounters many challenges, especially in intricate problems. In UAV deployment, costs of moving and energy consumption need to be considered, which provide constraints on assistance quality optimization. In problems of trajectory planning or routing, the communication environment changes rapidly, resulting in imperfect channel state information. Coordination, security, and power management also matter in related problems, making the algorithm design rather complicated [9]. Generally speaking, research on UAV-assisted communication mainly involves two aspects: one is the establishment of an air-ground communication model, and the other is the design and optimization of drone scheduling algorithms.