Coordinated Scheduling and Power Control for Non-Orthogonal Multiple Access (NOMA) enabled H-CRAN

Abstract

In this paper, the performance analysis of non-orthogonal multiple access (NOMA) in heterogeneous cloud radio access networks (H-CRAN) is carried out, where coordination of macro base station (MBS) and remote radio heads (RRHs) for H-CRAN with NOMA is introduced to improve network performance. We formulate the problem of jointly optimizing user association, coordinated scheduling and power allocation for NOMA-enabled H-CRANs. To efficiently solve this problem, we decompose the joint optimization problem into two subproblems as 1) coordinated scheduling 2) power allocation optimization. Firstly the users are divided based on interferences they suffer from. This interference-aware NOMA approach account for the inter-tier interference. Based on the user scheduling scheme, optimal power allocation optimization is performed by the hierarchical decomposition approach. Simulation results show that the proposed NOMA-enabled H-CRAN outperforms orthogonal multiple access (OMA)-based H-CRANs in terms of total achievable rate, interference mitigation and can achieve significant fairness improvement.