Performance analysis of NOMA aided cooperative relaying over α-η-κ-μ fading channels

In this paper, we investigate the outage analysis of Millimeter wave (mmWave) non-orthogonal multiple access (NOMA) based cooperative relaying system. We consider that the source communicates with user equipment with the aid of decode and forward relay using power domain downlink NOMA, and by sending messages in two time slots. Moreover, the α-η-κ -μ fading channel is considered between source, relay and user equipment, which is recently proposed in literature as a good fit model for mmWave communication. To this end, we derive the analytical expression for outage probability in terms of channel fading parameters. In order to gain insights at high SNR, asymptotic analysis for outage probability is carried out. Furthermore, analysis of achievable sum rate is also studied. Findings suggest that the considered channel model provides comparative diversity gain than the other fading channels. Proposed analytical expressions are verified by Monte Carlo simulations. We observe that at high SNR, diversity order depends only on the number of the scattered clusters and on the non linearity of the medium i.e. diversity order is αμ/2.