Performance analysis of UAV multiple antenna-assisted small cell network with clustered users

The emerging unmanned aerial vehicles (UAVs) are playing an important role to assist cellular networks and provide ubiquitous coverage for cellular networks. UAVs can eventually increase capacity and facilitate line-of-sight connections. In this paper, we develop an analytical framework to analyze coverage probability for UAVs-assisted small base stations (SBSs) with clustered users, taking into consideration mm-Wave and directional beamforming. Moreover, the contributions mainly include the consideration of multiple-input-multiple-output (MIMO) transmission. Additionally, the clustered user’s locations are modeled as Matern cluster process (MCP). Using tools from stochastic geometry, we derive a general expression for coverage probability according to the signal-to-interference-plus-noise ratio, by considering interference between UAVs and SBSs. The analytical results are validated using Monte-Carlo simulations in which the transmit power of SBS and UAV are considered to be 30 and 24 dBm respectively along with a carrier frequency of 28 GHz. The association probability is calculated as a function of cluster size and UAV density with different values of UAV height. Similarly, the coverage probability is computed as a function of SINR. It is observed from the results that the association probability depends on the altitude of the deployed UAVs and the typical height of a UAV should be between 40–120 m in order to achieve maximum association with a user. Further, it is observed that an upsurge in the density of UAVs and cluster size also affects the association criterion.