Abstract
This paper jointly studies cognitive radio (CR) and non-orthogonal multiple access (NOMA) networks by adopting an energy restricted amplify-and-forward relay. We study the outage performance of NOMA secondary destination users (U1and U2). Then, power allocation (PA) factors based on the NOMA users' outage fairness are evaluated for different distances of NOMA users. Furthermore, the outage performance for CR-NOMA is compared to the traditional CR orthogonal multiple access approach, where the former technique shows the better performance than the latter one. Moreover, we show the relation between the amount of harvested power and the power-splitting factor. Finally, the theoretical results are validated by the Monte Carlo simulations.