SWIPT-Enabled Cellular-Connected UAV: Energy Harvesting and Data Transmission

Achieving green unmanned aerial vehicle (UAV) communications is highly desirable in future 6G communication networks. In this regard, this work investigates a cellular-connected UAV served by downtilted terrestrial base station (BS) antennas in the downlink using simultaneous wireless information and power transfer (SWIPT). We consider a network where in the first time slot, the UAV harvests energy from aggregate transmissions of the BSs and in the second time slot, the UAV is served by the nearest BS. In such a network, there is an inherent trade-off between energy harvesting and data transmission performance which is impacted by the UAV height and directional BS and UAV antenna models. To characterize this trade-off, we derive the power coverage probability (which char-acterizes the energy harvesting performance) and the channel coverage probability (which characterizes the data transmission performance) using stochastic geometry. The analytical results are verified by simulations. Our results show that there is an optimal height of the UAV to maximize the channel coverage probability, subject to the power coverage probability constraint. For the urban scenario, as an example, a maximum channel coverage probability of over 82% can be achieved with a UAV height around 48 m for power coverage requirement of less than 90%. The results demonstrate the potential of SWIPT to support and enhance cellular-connected UAVs.