Computation-Intensive Status Update in UAV Relay-Assisted IoT with Short Packet Communications

Abstract

Unmanned aerial vehicle (UAV) can act as a flexible relay to help Internet of things (IoT) devices transmit real-time status information to the control center. Due to the variety and complexity of original data in some real-time applications, computation-intensive status update should be considered. To this end, this paper considers a computation-intensive status update in UAV relay-assisted IoT, where the short packet communication is adopted and the original data collected by a IoT device need to be calculated in the IoT device, relay or control center. To realize the trade-off optimization of age of information (AoI) and energy consumption, we first derive the closed-form expressions of average peak AoI, the average energy consumption of both IoT device and UAV under the condition of non-zero packet error probability (PEP). Then, we formulate the minimization problem of the weighted sum of the three performance metrics above, where the UAV locations, packet length and computing strategy are optimized jointly. Finally, an alternative optimization algorithm is proposed to obtain the sub-optimal solution. Simulation results show that the proposed algorithm can achieve efficient status update with low energy consumption and improve the performance effectively with the appropriate maximum tolerable PEP and the adaptive computing strategy.