Joint Task Allocation and Power Optimization in Multi-UAV Systems: An Overlapping Coalition Formation Game Approach

Multiple Unmanned Aerial Vehicle (multi-UAV) systems are capable of executing tasks and transmitting data effectively through cooperation. However, most existing works mainly focus on non-overlapping coalition formation and independent data transmission, which does not fully utilize the capability of UAV. This article investigates the cooperative task allocation of multi-UAV systems with consideration of limited UAV communication energy. In order to improve cooperative task performance, we jointly optimize overlapping coalition formation and UAVs' transmit power within the communication energy budget. Specifically, the problem is formulated as an overlapping coalition formation game (OCFG) in order to model the interactions among UAVs. In addition, a multi-coalition-based altruistic (MCA) order is proposed to support the overlapping of coalition members. The modeled OCFG is strictly proved to be an exact potential game (EPG), and hence the existence of stable coalition sturcture is guaranteed. Furthermore, we derive the conditions for UAV transmit power adjustment and develop a Joint Overlapping Coalition Formation and Transmit Power Optimization (JOCFTPO) algorithm to obtain the stable coalition structure. Finally, simulation results demonstrate that the proposed JOCFTPO algorithm outperforms the benchmark schemes in terms of the network utility.