Analysis of partial relay selection in NOMA systems with RF energy harvesting

In this paper, we investigate a dual hop communication decode-and-forward relaying system where a source node wants to transmit two symbols to its two desired destinations with the help of a selected energy constraint relay node. The power for relay operation comes from the harvested energy of ambient radio frequency (RF) and the non-orthogonal multiple access (NOMA) technology is used. We mathematically evaluate the impact of relay selection (RS) on the system performance by considering the probability that symbols cannot be decoded at the two end users under the effect of imperfect and perfect successive interference cancellation (SIC). We also perform Monte-Carlo simulations in MATLAB to verify the correctness of our analysis. The results show that the performance of the system is significantly influenced by the efficiency of SIC technique. Moreover, if the power transmission is in high region, we can use approximation method to simplify our analysis.