Non-Orthogonal Multiple Access with Coordinated Transmission Aided by Buffers in End User and Relay

In this paper, we investigate a buffer-aided nonorthogonal multiple access (NOMA) system with coordinated direct and relay transmission (CDRT), in which the buffers are equipped in user equipment 1 (UE1) directly connected to a base station (BS) and a relay, respectively. With the buffer, UE1 can perfectly remove interference from the relay when the relay delivers the received signal. We provide the mean service rate of the proposed system as well as two benchmark systems and compare their performances. Numerical investigation shows that the proposed method is promising especially when BS power is relatively greater than relaying power.