On the Performance of RIS-Aided NOMA System with Non-ideal Transceiver over Nakagami-m Fading

Reconfigurable intelligent surfaces (RISs) have recently been envisioned to provide an adaptable channel for futuristic wireless communication networks. In this work, we investigate a downlink RIS-aided non-orthogonal multiple access (NOMA) wireless networks, where a RIS is deployed to enhance users’ performance communicating with the base station (BS) in the presence of a non-ideal transceiver. Specifically, closed-form expressions for the outage, spectral efficiency (SE) and energy efficiency (EE) are derived. The results demonstrate that the non-ideal transceiver has a detrimental impact on the performance of the RIS-aided NOMA system. The proposed analysis also shows that for a RIS-aided NOMA system with a non-ideal transceiver, there exists an upper bound on SE that is independent of the transmit power and the number of reflecting elements in the RIS. Additionally, the performance of the NOMA system is compared with its OMA counterpart, where the results show that for a non-ideal transceiver-based system, the RIS-aided NOMA outperforms OMA.