Modeling and Coverage Analysis of Power Control in User-Centric UAV Networks

In unmanned aerial vehicle (UAV) networks, line-of-sight (LOS) links dominate the communication among UAV transmission points (TPs) and user equipments (UEs), which tremendously improves link quality but also leads to strong interference. This paper proposes a power control strategy to combat interference in user-centric UAV networks, where a dynamic UAV transmission point group (TPG) is organized serve each user seamlessly. Based on the strategy, semi-closed expression of network downlink coverage probability is derived leveraging stochastic geometry analysis with the consideration that different TPGs can overlap with each other. Specifically, each UE would choose the closest UAV as its serving UAV to transmit data while other UAVs within the TPG will mitigate interference by reducing transmitting power. Two coefficients mu and beta are applied to determine the area and intensity for power control, which can realize the tradeoff between interference mitigation and resource utilization. The results show that with the power control strategy we proposed, coverage probability can be improved at most by 66% when the SIR threshold is 10 dB.