  Non-orthogonal multiple access (NOMA) is a promising technique for the fifth
generation (5G) wireless communications. As users with good channel conditions
can serve as relays to enhance the system performance by using successive
interference cancellation (SIC), the integration of NOMA and cooperative
relaying has recently attracted increasing interests. In this paper, a
NOMA-based cooperative relaying system is studied, and an analytical framework
is developed to evaluate its performance. Specifically, the performance of NOMA
over Rician fading channels is studied, and the exact expression of the average
achievable rate is derived. Moreover, we also propose an approximation method
to calculate the achievable rate by using the Gauss-Chebyshev Integration.
Numerical results confirm that our derived analytical results match well with
the Monte Carlo simulations.
