UAV-Assisted Wireless Networks: Mobility and Service Oriented Power Allocation and Trajectory Design

In this paper, we consider a downlink wireless network assisted by single unmanned aerial vehicle (UAV) in an area with no-fly zones (NFZs), where there are multiple moving users with diverse quality of service (QoS) requirements to be served. In addition to the cylindrical NFZs, we also modeled and analyzed the polygonal NFZs that are common in reality but seldom investigated in research. We aim to maximize the sumrate of all user by jointly optimizing the power allocation and trajectory design of the UAV under the constraints on the limited power resource, the QoS requirements of users and the NFZs evasion for UAV. Since the formulated joint optimization problem is non-convex, to deal with it, we design a low-complex iterative scheme based on the proposed modified water-filling algorithm, the successive convex approximation (SCA) technology, disjunctive programming and penalty functions. The simulation results show that the proposed algorithm can significantly increase the system sum-rate while ensuring the QoS requirements of all users, reasonably evading the NFZs and adapting well to the real-time mobility of uses.