Joint Design of Hybrid Beamforming and Phase Shifts in RIS-Aided mmWave Communication Systems

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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Joint Design of Fronthauling and Hybrid Beamforming for Downlink C-RAN Systems

IEEE Transactions on Communications ◽

10.1109/tcomm.2019.2903142 ◽

2019 ◽

Vol 67 (6) ◽

pp. 4423-4434 ◽

Cited By ~ 5

Author(s):

Jaein Kim ◽

Seok-Hwan Park ◽

Osvaldo Simeone ◽

Inkyu Lee ◽

Shlomo Shamai Shitz

Keyword(s):

Joint Design ◽

Hybrid Beamforming

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Ergodic Secrecy Rate of RIS-Assisted Communication Systems in the Presence of Discrete Phase Shifts and Multiple Eavesdroppers

IEEE Wireless Communications Letters ◽

10.1109/lwc.2020.3044178 ◽

2020 ◽

pp. 1-1

Author(s):

Peng Xu ◽

Gaojie Chen ◽

Gaofeng Pan ◽

Marco Di Renzo

Keyword(s):

Communication Systems ◽

Phase Shifts ◽

Secrecy Rate ◽

Discrete Phase ◽

Ergodic Secrecy Rate

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Joint User Scheduling and MU-MIMO Hybrid Beamforming Algorithm for mmWave FDMA Massive MIMO System

International Journal of Antennas and Propagation ◽

10.1155/2016/4341068 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Jing Jiang ◽

Deting Kong

Keyword(s):

Multiple Access ◽

Mimo System ◽

Multiple Input Multiple Output ◽

Phase Shifts ◽

Base Station ◽

User Group ◽

Frequency Division ◽

User Scheduling ◽

Hybrid Beamforming ◽

Beamforming Algorithm

The large bandwidth and multipath in millimeter wave (mmWave) cellular system assure the existence of frequency selective channels; it is necessary that mmWave system remains with frequency division multiple access (FDMA) and user scheduling. But for the hybrid beamforming system, the analog beamforming is implemented by the same phase shifts in the entire frequency band, and the wideband phase shifts may not be harmonious with all users scheduled in frequency resources. This paper proposes a joint user scheduling and multiuser hybrid beamforming algorithm for downlink massive multiple input multiple output (MIMO) orthogonal frequency division multiple access (OFDMA) systems. In the first step of user scheduling, the users with identical optimal beams form an OFDMA user group and multiplex the entire frequency resource. Then base station (BS) allocates the frequency resources for each member of OFDMA user group. An OFDMA user group can be regarded as a virtual user; thus it can support arbitrary MU-MIMO user selection and beamforming algorithms. Further, the analog beamforming vectors employ the best beam of each selected MU-MIMO user and the digital beamforming algorithm is solved by weight MMSE to acquire the best performance gain and mitigate the interuser inference. Simulation results show that hybrid beamforming together with user scheduling can greatly improve the performance of mmWave OFDMA massive MU-MIMO system.

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2D-OPC Subarray Structure for Efficient Hybrid Beamforming over Sparse mmWave Channels

International Journal of Antennas and Propagation ◽

10.1155/2021/6680566 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Junhyuk Yoo ◽

Wonjin Sung ◽

In-Kyung Kim

Keyword(s):

Antenna Arrays ◽

Communication Systems ◽

Dimensional Space ◽

Path Loss ◽

Two Dimensional ◽

Hardware Cost ◽

Antenna Structure ◽

Digital Beamforming ◽

Trade Offs ◽

Hybrid Beamforming

Millimeter-wave (mmWave) communication is a key technology of 5G new radio (NR) mobile communication systems. Efficient beamforming using a large antenna array is important to cope with the significant path loss experienced in the mmWave spectrum. The existing fully digital beamforming scheme requires a separate radio frequency (RF) chain for each antenna, which results in an excessive hardware cost and consumption power. Under these circumstances, hybrid beamforming which approaches the performance of fully digital beamforming while reducing the complexity is a promising solution for the mmWave multiuser transmission. By extending the existing hybrid beamforming strategies, this paper proposes a novel architecture which effectively reduces the hardware cost and complexity for large antenna arrays. The proposed scheme includes multiple subarrays in the form of uniform planar array (UPA) which are allowed to be overlapped in the two-dimensional space. The corresponding antenna structure is referred to as the two-dimensional overlapped partially connected (2D-OPC) subarray structure. We evaluate the performance of the proposed scheme to suggest performance-complexity trade-offs in designing versatile antenna arrays for efficient beamforming over the mmWave channel.

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