Effective Rate of Multiuser NOMA Systems with Imperfect SIC for Beyond 5G Applications

In this paper, we compare the performance of the downlink of multi-user NOMA and OMA systems for the applications of the next generation of mobile communications with imperfect interference cancellation. The case we consider involves services with heterogeneous latency demands in a finite blocklength scenario. The effective capacity is used to assess the system’s performance, because it reflects the effect of estimation errors and time delay requirements. We calculate the achievable effective rates by numerical integration using the ordered statistics distributions for Rayleigh fading channels, and verify these results through Monte Carlo simulations. The performance of NOMA is evaluated considering different estimation errors and in terms of homogeneous and heterogeneous latency requirements.