Abstract:

The wireless communications regarding unmanned aerial vehicles (UAVs) have been investigated for the usage of base stations (BS) to provide Internet access. This paper presents the usage of a UAV as a pairing user to enhance the sum capacity by flexible pairing in nonorthogonal multiple access (NOMA). In the proposed scheme, the UAVs and the ground users (GUs) get paired to promote the line-of-sight (LoS) characteristics. The performance of flexible pairing is presented in terms of sum capacity, outage probability, and throughput with the LoS path loss. Channel modeling is necessary to apply flexible pairing by utilizing the LoS characteristic as a special case. Moreover, the height of the UAV is calculated based on the elevation angle. It is revealed that the LoS path loss determines the effect on the channel covariance. The analysis of the flexible pairing is shown with Monte Carlo-based simulation and analytic results are validated to maximize throughput.

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