Performance Study of Cooperative Non-Orthogonal Multiple Access with Energy Harvesting

Abstract

Non-orthogonal Multiple Access (NOMA) is a candidate channel access technique for the future-generations wireless communication systems. It exploits the power domain to enable simultaneous access for multiple users. In this project, a NOMA system with a base station (BS) and two users is studied. A novel scheme where the near user (UE 1) harvests energy from the signals sent from BS, and relays the previously decoded message of the far user (UE 2) is proposed. Different energy harvesting schemes are also investigated. The performance is evaluated by the achievable data rate of UE 2 under different requirements for data rate of UE 1. Numerical simulations reveal that when the channel conditions between BS and UE1, and between UE 1 and UE 2 are good, while that between BS and UE 2 is bad, the proposed scheme works the best and has a significant gain over traditional NOMA scheme. In addition, for the sake of simplicity, power splitting scheme can be used to replace the generalized scheme for energy extraction without jeopardizing the performance gain much.