Power allocation for full-duplex NOMA relaying based underlay D2D communications

Abstract

In this paper, a full-duplex NOMA relaying based underlay device-to-device (D2D) communication scheme is proposed, in which D2D transmitter assists cellular downlink transmission as a full-duplex relay. Specifically, D2D transmitter receives signals from base station and transmits the superposition signals to D2D receiver and cellular user in NOMA scheme simultaneously. Furthermore, we investigate the power allocation under the proposed scheme, aiming to maximize D2D link's achievable transmit rate under cellular link's transmit rate constraint and total power constraint. To tackle the power allocation problem, we first propose a power allocation method based on linear fractional programming. In addition, we derive closed-form expressions of the optimal transmit power for base station and D2D transmitter. Simulation results show that the performance of two solutions matches well and the proposed full-duplex NOMA relaying based underlay D2D communication scheme outperforms existing full-duplex relaying based D2D communication scheme.

Optimal Power Allocation for NOMA-based Cellular Two-Way Relaying

“…Non-orthogonal multiple access (NOMA) is an efficient multiple access technique to support massive connections in Internet of Things (IoT) networks [1] [2]. In a typical power-domain NOMA system, multiple users' signals are assigned with different power levels, and user with stronger channel gain needs to decode signals of other weaker users before decoding its own signal using successive interference cancellation (SIC).…”

Sum-Rate Performance of A NOMA-based Two-Way Relay Approach for A Two-User Cellular Network

“…Non-orthogonal multiple access (NOMA) is a promising solution to improve the spectral and energy efficiency of wireless communication networks [1] [2]. By allowing multiple wireless terminals share the same radio resources, NOMA significantly improves transmission efficiency as compared with conventional time-division multiple access (TDMA) or frequency-division multiple access (FDMA) schemes.…”