Outage Performance of Two Users Cooperative NOMA with Energy Harvesting Relay

Non Orthogonal Multiple Access (NOMA) is considered as a potential technique for next generation networks. In this paper a cooperative relay scheme for two users NOMA using an energy harvesting Decode and Forward relay is investigated. The relay harvests energy from the Radio Frequency signals of the two sources following a Time Switching (TS) protocol and transmits information of the sources to their respective destinations following the principal of NOMA. Successive interference cancellation is used at the destinations to decode their signals. More precisely, we evaluate the system outage performance for the proposed scheme. A closed form analytical expression for the outage probability of the considered scheme is developed. Impact of several network parameters such as source transmit power, time switching coefficient, power allocation coefficient of NOMA is indicated. Analytical results are validated by MATLAB based simulation. We observe existence of optimal values of time switching coefficient, power allocation coefficient, signal-to-interference ratio of source which minimizes the system outage probability under a given scenario.