Performance Analysis in UAV-enabled Relay with NOMA under Nakagami-m Fading Considering Adaptive Power Splitting

This paper investigates the system performance of an energy harvesting (EH) unmanned aerial vehicle (UAV)-enabled relay (UR) in the Internet of Things (IoT) under Nakagami-m fading, where the UR applied time switching (TS) and adaptive power splitting (APS) (U-TSAPS). To increase throughput, all links (i.e., from the base station (BS) to the UR and from the UR to the IoT device (Id) clusters) are transmitted using the nonorthogonal multiple access (NOMA) technique. The U-TSAPS protocol is divided into two stages. In the first stage, the BS chooses the best antenna for transmitting the signal to the UR. The UR then divides the received signal into two streams, one for information processing and the other for the EH. In the second stage, the UR uses the decode-and-forward (DF) scheme to send the obtained signal to the best far device (BFD) in the far cluster and the best near device (BND) in the near cluster. Under imperfect channel state information (ICSI) details, we derive closed-form expressions for the outage probability (OP) of BFD and BND with the APS ratio to evaluate device efficiency. These derivations are also used to evaluate the throughput of the system under consideration. Monte Carlo simulations are used to validate our system.