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

Abstract

In this paper, we investigate the combination of nonorthogonal 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 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 suboptimal solution can achieve a near-upper-bound performance in terms of ASR, which is significantly improved compared with those of the state-of-the-art schemes and the conventional mmWave orthogonal multiple access (mmWave-OMA) system.Index Terms-millimeter-wave communications, NOMA, Tx-Rx beamforming, power allocation, particle swarm optimization.

User Grouping and Power Allocation for Downlink NOMA-Based Quadrature Spatial Modulation

“…Furthermore, in cooperative NOMA systems, relay location optimization algorithms were considered to minimize the outage probability [19], a closed-form expression for the throughput under the delay-limited transmission mode was presented [20], and the approximate expression for the ergodic sum rate was derived [21]. The ASR maximization problem was considered in NOMA-millimeter wave systems, where the gradient ascent method and the gradient descent method were presented for power allocation [22]. The robust interference efficiency maximization problem was studied for multicell heterogeneous networks (HetNets), where perfect and imperfect channel state information (CSI) were considered [23].…”

Spatial-Temporal-DBSCAN-Based User Clustering and Power Allocation for Sum Rate Maximization in Millimeter-Wave NOMA Systems

“…Initially, to reduce the inter-cluster interference, an approximate zero-forcing (AZF) method is used to design the DBF, where the ABF matrix is fixed and arbitrary. Next, the BC-PSO algorithm is utilized to deal with the ABF problem [49]. A summary of this solution is shown below.…”

Spectral-Energy Efficiency Trade-Off-Based Beamforming Design for MISO Non-Orthogonal Multiple Access Systems

“…Different disruptive technologies, including massive multiple-input multiple-output (MIMO) [4] [5], millimeterwave (mmWave) [1] [6] [7], and non-orthogonal multiple access (NOMA) techniques [8] have been proposed to meet the stringent design and operational requirements surrounding EE and SE. In particular, NOMA has been envisioned as one of the key techniques for significantly improving the SE while providing massive connectivity to support the Internetof-Things (IoT) in 5G and beyond wireless networks [9].…”