Resource Allocation for 3D Drone Networks Sharing Spectrum Bands

This paper provides an appropriate allocation scheme of channel resources for drone communications. In recent years, the usage of drones has been increasing for a wide range of applications, and their communications require using additional frequency bands. However, their communications must avoid interference with primary users (e.g., radar systems) when they use additional frequency bands. We assume that their communications use two frequency bands, the main band and the backup band, to avoid interference. The proposed resource allocation method, which determines whether each drone should use the main or the backup bands, enables drone communications to use the main band efficiently without causing interference. For the proposed resource allocation scheme, this paper presents a stochastic geometry analysis of interference in drone networks. Based on the assumption that the distribution of drones follows a 3D Poisson point process, we analytically derive the radar's outage probability (OP) and the drone's OP. From these analyses, an optimization problem is formulated to maximize the number of drones using the main band, since drones can transmit massive amounts of data by using the main band. Then, we numerically evaluate the solution of the optimization problem. Our results show that the maximum ratio of the number of drones using the main band to the total number of all drones increases along with the size of the primary exclusive region.