Adaptive Transmission for Cooperative NOMA System With Buffer-Aided Relaying

We study a cooperative non-orthogonal multiple-access (NOMA) system with buffer-aided relaying. By assuming that the relay node possesses a buffer, we propose an adaptive transmission scheme in which the system adaptively chooses its working mode in each time slot. The optimal mode selection scheme that maximizes the sum throughput of the NOMA users is obtained. Numerical results validate our analysis and show that the proposed adaptive transmission scheme can improve the system throughput.