Outage performance of NOMA over α-μ, η-μ and α-η-μ faded channels with imperfect CSI and interference

For future wireless communications, non-orthogonal multiple access (NOMA) is very promising. This paper evaluates the outage performance of multi-user (MU) NOMA in non-homogeneous fading environment. The closed-form expressions of outage probability are obtained over alpha-mu, eta-mu and alpha-eta-mu faded channels. Here, we obtained the expressions considering the effect of channel estimation error, intra and inter-cellular interference. The obtained expressions can also be used to asses the outage performance of NOMA over common faded channels as special cases. The derived expressions are very helpful to evaluate the impact of interference and channel estimation error on the performance of NOMA with different fading parameters. The analytical results are presented for two users which are at near and edge positions of a Voronoi cell. Finally, simulated results are presented to validate the derived expressions.