Energy-Efficient and QoS-aware UAV Communication using Reactive RF Band Allocation

Next generation mobile communication systems propose the use of Unmanned Aerial Vehicles (UAVs) in providing wireless communication services. Emerging bandwidth-demanding applications such as real-time video streaming could also be satisfied by the next generation UAVs while exploiting the unoccupied bandwidth available at millimetre Wave (mmWave) frequency ranging from 30 to 300 GHz. However, mmWave UAVs suffer from high attenuation loss and Line Of Sight (LOS) communication. To combat the attenuation, UAVs must transmit using higher transmission power which results in higher energy consumption. MmWave, however, incurs shorter communication sessions implying shorter flight duration and less energy consumption than Long-Term Evolution (LTE) band for delivering the same service. Furthermore, a wide range of applications are delay sensitive and unable to be served by LTE. Since mmWave UAVs require continuous LOS and are unable to serve concurrent multiple nodes, we explore the concept of dual-mode UAV-assisted service delivery in which the UAV switches to mmWave band for serving bandwidth-hungry applications, and back to LTE for all other applications. The aim is to achieve a trade-off between Quality of Service (QoS) and energy consumption for Air2Ground (A2G) service delivery. Our evaluation results show the feasibility of such dual-mode system for next generation UAVs while achieving higher QoS compared to the current mono-band UAVs.