Resource Allocation for URLLC-Oriented Two-Way UAV Relaying

Due to the high altitude and deployment flexibility, unmanned aerial vehicles (UAVs) can be used as relays to avoid obstacles and extend the coverage of wireless networks. On the other hand, ultra-reliable and low-latency communication (URLLC) is often required to deliver the information reliably and timely for many emerging applications. In this correspondence, we combine the advantages of both UAV and URLLC to investigate the resource allocation for a URLLC-enabled two-way UAV relaying system. Our goal is to maximize the transmission rate of the backward link with the constraint of URLLC requirement for the forward link. The optimization is non-convex and difficult to solve. Therefore, the optimization variables are divided to several blocks, and three sub-problems are formulated and solved. Finally, an iterative algorithm is proposed to solve these sub-problems alternately. Simulation results show that the proposed joint optimization scheme can achieve excellent performance for the URLLC-enabled two-way UAV relaying system.