Outage Probability of Wireless Powered Cooperative NOMA over Fluctuating Two-Ray Fading

This paper investigates the outage probability of a cooperative non-orthogonal multiple access (NOMA) system over fluctuating two-ray (FTR) fading channels. The scenario considered is a downlink scenario consisting of one source node and two receiving nodes. The node closest to the source node acts as a relay, forwarding the data of the other receiving node using the selective decode-and-forward (DF) protocol. The nearby node is energy-constrained and its transmission depends on the energy harvested using the radio frequency (RF) signal transmitted by the source node. The end-to-end communication occurs in three time slots: the first slot is dedicated to wireless power transmission from the source node to the nearby node, while the next two slots involve cooperative NOMA transmission. Analytical expressions for the end-to-end outage probability of the two users are derived. The corresponding analytical results are validated with simulation results. Insightful findings are presented for various fading parameter settings.