Performance of Two Stage Cooperative NOMA Transmission for Full-Efficient Three User Network

In this paper, we investigate the performance of three user network with two-stage non-orthogonal multiple access (NOMA) scheme. In particular, the outage performance is analyzed by considering full efficiency information transmission protocol, where each user receives its own data symbol in every slot. We investigate outage performance metric at each user, and obtained closed-form expressions. Moreover, a novel fragmental outage probability at near users is evaluated, which is useful for obtaining optimum NOMA power allocation coefficients. The results demonstrate that the considered scheme outperform conventional NOMA and optimal NOMA parameter selection maximizes the system performance. Simulation results corroborate the derived analytical expressions.