UAV aided FD-NOMA for Energy-efficient Ultra-Reliable Low-latency Communications

Abstract

Unmanned aerial vehicle (UAV) aided network and ultra-reliable low-latency communication (URLLC) systems are expected to enable a new paradigm for future mission-critical and military communications. This paper considers a novel framework of energy-efficient resource allocation design for a UAV-aided full-duplex non-orthogonal multiple access (FD-NOMA) system with URLLC. In particular, we formulate a problem of energy-efficiency maximization subject to the joint design of 3-D UAV placement and power allocation for uplink (UL) and downlink (DL) users of the FD-NOMA system under a finite block-length regime. We propose an alternating optimization framework where the problems of power allocation and UAV placement are alternatively solved using general convex approximation techniques and simulated annealing algorithms, respectively. Finally, numerical results are presented to validate the effectiveness and the superiority of the proposed UAV-aided FD-NOMA URLLC system over conventional orthogonal multiple access (OMA) and half-duplex (HD-NOMA) schemes, while maintaining low packet-size and high reliability.