Joint Tx-Rx Beamforming and Power Allocation for 5G Millimeter-Wave Non-Orthogonal Multiple Access Networks

• Published in: IEEE transactions on communications Vol. 67; no. 7; pp. 5114 - 5125
• Main Authors: Zhu, Lipeng, Zhang, Jun, Xiao, Zhenyu, Cao, Xianbin, Wu, Dapeng Oliver, Xia, Xiang-Gen
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.07.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: 5G mobile communication; Algorithms; Array signal processing; Beamforming; Closed form solutions; Decoding; Downlink; Exact solutions; Mathematical analysis; Millimeter waves; Millimeter-wave communications; NOMA; Nonorthogonal multiple access; Particle swarm optimization; Phased arrays; power allocation; Power management; Production scheduling; Radio frequency; Resource management; Tx-Rx beamforming
• ISSN: 0090-6778; 1558-0857
• DOI: 10.1109/TCOMM.2019.2906589

In this paper, we investigate the combination of non-orthogonal multiple access and millimeter-wave communications (mmWave-NOMA). A downlink cellular system is considered, where an analog phased array is equipped at both the base station and users. A joint Tx-Rx beamforming and power allocation problem is formulated to maximize the achievable sum rate (ASR) subject to a minimum rate constraint for each user. As the problem is non-convex, we propose a sub-optimal solution with three stages. In the first stage, the optimal power allocation with a closed form is obtained for an arbitrary fixed Tx-Rx beamforming. In the second stage, the optimal Rx beamforming with a closed form is designed for an arbitrary fixed Tx beamforming. In the third stage, the original joint Tx-Rx beamforming and power allocation problem is reduced to a Tx beamforming problem by using the previous results, and a boundary-compressed particle swarm optimization (BC-PSO) algorithm is proposed to obtain a sub-optimal solution. Extensive performance evaluations are conducted to verify the rational of the proposed solution, and the results show that the proposed sub-optimal solution can achieve a significantly better performance in terms of ASR compared with those of the state-of-the-art schemes and the conventional mmWave orthogonal multiple access (mmWave-OMA) system.