Uplink non-orthogonal multiple access protocol in two-way relaying networks: realistic operation and performance analysis

In this paper, we study a two-way non-orthogonal multiple access cooperative schemes with two sources and the aid of a decode-and-forward relay under the overall effects of perfect/imperfect successive interference cancellation and perfect/imperfect channel state information. In this scheme, the digital network coding technique is used at the relay to decrypt sequentially the received data from sources, then encode these data by the XOR operation and transmit back to the sources. System performance in terms of outage probabilities and throughput is analyzed by exact and asymptotic closed-form expressions. Besides, the proposed protocol performance is compared to the performance of a conventional two-way scheme. The Monte Carlo simulation results evidence the validity of the analysis expressions.