Efficient 3D placement of drone base stations with frequency planning

Abstract

It is anticipated that unmanned aerial vehicle base stations (UAV-BSs) will play a role in compensating network outages in case of temporary/unexpected events on account of flexibility. However, one of the key issues is how to deploy them efficiently. In this paper, the coverage, capacity and interference constraints are jointly considered, making the 3D placement more practical. Given available UAV-BS number, frequency band number and ground user distribution, the optimization objective is to maximize the number of serviced users and it is formulated into a mixed integer non-linear problem. Thereupon we develop a heuristic algorithm to find a suboptimal solution with polynomial time complexity. Numerical results show that available UAV-BS number is the critical factor of serviced user percent when user density is high, while the maximal allowable coverage radius is the critical factor when user density is low.