Impact of IQI on Sum Rate of mmWave Massive MU-MIMO Systems with Hybrid Beamforming

This paper proposes a high performance wireless commmunication technology in MU-MIMO systems. The millimeter wave (mmWave) communication technology was considered for the future wireless communication systems such as the fifth-generation new radio (5G NR). In 5G NR, the mmWave communication technology was studied to increase the use of wide bandwidth and the data rate. Therefore, MU-MIMO systems can be used in mmWave. To decrease the complexity of conventional digital beamforming system, the hybrid beamforming system was studied. In particular, the proposed hybrid beamforming system improves the error performance and average sum rate in partially connected structure (PCS) hybrid beamforming system. The proposed PCS hybrid beamforming system forms variously combined beam patterns using the information of azimuth and elevation angles for the multi-paths according to the number of bits. In addition, the azimuth and elevation angles among the formed beam patterns are estimated according to the received signal strength (RSS). In the simulation results, the proposed PCS hybrid beamforming system has better error performance and the average sum rate than the conventional hybrid beamforming system.

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Mixed Time Scale Weighted Sum Rate Maximization for Hybrid Beamforming in Multi-Cell MU-MIMO Systems

2017 IEEE Globecom Workshops (GC Wkshps) ◽

10.1109/glocomw.2017.8269180 ◽

2017 ◽

Cited By ~ 3

Author(s):

Christo Kurisummoottil Thomas ◽

Dirk Slock

Keyword(s):

Time Scale ◽

Mimo Systems ◽

Weighted Sum ◽

Rate Maximization ◽

Sum Rate Maximization ◽

Sum Rate ◽

Hybrid Beamforming ◽

Weighted Sum Rate ◽

Weighted Sum Rate Maximization

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Spatio-Radio Resource Management and Hybrid Beamforming for Limited Feedback Massive MIMO Systems

Electronics ◽

10.3390/electronics8101061 ◽

2019 ◽

Vol 8 (10) ◽

pp. 1061 ◽

Cited By ~ 3

Author(s):

Hedi Khammari ◽

Irfan Ahmed ◽

Ghulam Bhatti ◽

Masoud Alajmi

Keyword(s):

Massive Mimo ◽

Fourier Transforms ◽

Mimo Systems ◽

Limited Feedback ◽

Base Station ◽

Discrete Fourier Transforms ◽

Beam Selection ◽

Sum Rate ◽

Hybrid Beamforming ◽

Csi Feedback

In this paper, a joint spatio–radio frequency resource allocation and hybrid beamforming scheme for the massive multiple-input multiple-output (MIMO) systems is proposed. We consider limited feedback two-stage hybrid beamformimg for decomposing the precoding matrix at the base-station. To reduce the channel state information (CSI) feedback of massive MIMO, we utilize the channel covariance-based RF precoding and beam selection. This beam selection process minimizes the inter-group interference. The regularized block diagonalization can mitigate the inter-group interference, but requires substantial overhead feedback. We use channel covariance-based eigenmodes and discrete Fourier transforms (DFT) to reduce the feedback overhead and design a simplified analog precoder. The columns of the analog beamforming matrix are selected based on the users’ grouping performed by the K-mean unsupervised machine learning algorithm. The digital precoder is designed with joint optimization of intra-group user utility function. It has been shown that more than 50 % feedback overhead is reduced by the eigenmodes-based analog precoder design. The joint beams, users scheduling and limited feedbacK-based hybrid precoding increases the sum-rate by 27 . 6 % compared to the sum-rate of one-group case, and reduce the feedback overhead by 62 . 5 % compared to the full CSI feedback.

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