Power splitting protocol design for the cooperative NOMA with SWIPT

In this paper, we consider the simultaneous wireless information and power transfer assisted cooperative nonorthogonal multiple access (SWIPT-CNOMA) system, in which the near NOMA users with strong channel conditions serve as energy harvesting (EH) relays to help the far NOMA users with poor channel conditions. For the considered system, a new power splitting (PS) protocol for EH relay is proposed and its impact on the outage performance of both near and far NOMA users is studied. The analytical expressions of both outage probability and system throughput are further derived for delay-sensitive transmission mode. Simulation results are provided to verify the derived results and reveal the advantages of the proposed protocol.