Tradeoffs for Data Collection and Wireless Energy Transfer Dilemma in IoT Environments

Recently, UAV has provided a significant role to support the wireless network, thanks to the several advantages that can offer in comparison with the terrestrial base station. In this paper, we aim to deal with data collection and charging depletion ground IoT devices through UAV station, which is used as a flying base station. To extend the network lifetime, we present a novel use of UAV with energy harvesting module. Thus, the UAV can be used as an energy source to serve depleted IoT devices. On one hand, the UAV charges the depletion ground IoT devices starting initially with those with battery level under a certain threshold. On the other hand, the UAV station collects data from IoT devices that have sufficient energy to transmit their packets, and in the same phase, the UAV exploits the RF signals transmitted by IoT devices to extract and harvest energy. Furthermore, and as the UAV station has a limited coverage time due to its known energy constraint, we investigate in this work the trade- off between both times that the UAV reserves to devices in order to recharge them and to collect data. Numerical results evaluate different metrics of performances in which we examine the added value of UAV with energy harvesting module.