User-Centric Intelligent UAV Swarm Networks: Performance Analysis and Design Insight

To enhance the network coverage and capacity, unmanned aerial vehicle (UAV) communication has become a promising technology thanks to the high mobility and the flexible deployment of UAVs. However, the consistency of the service is not guaranteed due to the limitation single UAV base station (BS), leading to the research for the user-centric UAV swarm networks. This paper derives the semi-closed-form expressions of coverage probability and average achievable rate for the user-centric UAV swarm networks to characterize the performance gain obtained from the increased UAV swarm diversity. Especially, the user-centric UAV swarm networks organize a dynamic UAV swarm for each user consisting of potential serving UAVs in user's vicinity, which gives the design of boundaryless cells to serve each user seamlessly without user's involvement. By modeling the locations of the UAVs as Poisson point process (PPP) and modeling the channel fading as Nakagami-$m$ distribution, the analytical results are calculated under two transmission modes, depending on whether cell coordination is considered or not. The results show that the coverage performance can be improved by 30% without cell coordination and 50% with cell coordination in comparison with traditional cell-centric networks when the UAV altitude is 100 m and SINR threshold is 0 dB.