OUTAGE PERFORMANCE OF FULL-DUPLEX UNMANNED AERIAL VEHICLE-AIDED COOPERATIVE NON-ORTHOGONAL MULTIPLE ACCESS

Unmanned Aerial Vehicles (UAVs) are envisioned to play a key role in the Sixth-Generation (6G) and Beyond Fifth-Generation (B5G) networks. Resolving spectrum constraints in UAV communications remains a critical issue. This article investigates Full-Duplex (FD) UAV-aided Non-Orthogonal Multiple Access (NOMA) to effectively utilise the scarce wireless spectrum. Specifically, exact closed-form formulas for the outage probability of FD UAV-aided NOMA have been developed. The results are validated using Monte Carlo simulation in 3GPP UMi conditions to provide practical guidelines for real-world deployment. In low transmission power regimes, the results also reveal that FD UAV-aided NOMA has a lower outage probability at the downlink Ground Users (GUs) than HD UAV-aided NOMA. At high transmit power regimes, FD UAV-aided NOMA is limited by residual SI at the UAV and interference from the UAV to the GUs. The numerical results also show that the transmission power at the UAV should be significantly lower than that at the Ground Base station (GB) to ensure low outages at the GUs.

Automated summary

This article investigates the application of Full-Duplex (FD) UAV-aided Non-Orthogonal Multiple Access (NOMA) in resolving spectrum constraints in UAV communications. Closed-form formulas for the outage probability of FD UAV-aided NOMA have been developed and validated through Monte Carlo simulation and experimental verification in 3GPP UMi conditions. The results show that FD UAV-aided NOMA has a lower outage probability at the downlink Ground Users (GUs) compared to HD UAV-aided NOMA in low transmission power regimes. However, in high transmit power regimes, FD UAV-aided NOMA is limited by residual self-interference at the UAV and interference from the UAV to the GUs.