Low Complexity Hybrid Beamforming for MmWave-UAV Communication Systems with a Pre-defined Codebook

Unmanned Aerial Vehicles (UAVs) have been regarded as a candidate for future networks with high capacity requirement. However, the high mobility and agility of UAVs make the designation of the cooperative communication system more complex than that of the traditional terrestrial cell network, how to construct an aerial network efficiently for terrestrial terminals or users is still a hot spot. In this paper, we investigate the UAV-based wireless communication system where the detection performance for each user needs to be guaranteed. We mainly focus on two different types of communication systems, in the first kind of systems, the UAVs will hover above the targeted cell to communicate with different users simultaneously. A low complexity hybrid beamforming method for the UAV with finite resolution phase shifters (PSs) is proposed. Moreover, for the second type of UAV-based systems, the UAV can communicate with different user groups where only one user in a group could be motivated during a transmission block. We then propose an effective multiuser selection scheme to improve the efficiency of the system. Finally, from the simulation, we can confirm that the proposed methods are reasonable and attractive to the UAV-based communication system.