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An Overview of Massive MIMO: Benefits and Challenges

Lu Lu, Geoffrey Ye Li, A. Lee Swindlehurst, Alexei Ashikhmin, Rui Zhang
2014 IEEE Journal on Selected Topics in Signal Processing  
We particularly focus on the potential impact of pilot contamination caused by the use of non-orthogonal pilot sequences by users in adjacent cells.  ...  Finally, the challenges and opportunities associated with implementing massive MIMO in future wireless communications systems are discussed.  ...  Multi-User MIMO MU-MIMO systems can obtain the promising multiplexing gain of massive point-to-point MIMO systems while eliminating problems due to unfavorable propagation environments.  ... 
doi:10.1109/jstsp.2014.2317671 fatcat:x3hzg3mmizanlnei4lir6z6m4a

Can Massive MIMO Support Uplink Intensive Applications? [article]

Hong Yang, Erik G. Larsson
2019 arXiv   pre-print
Via the newly derived SINR expressions for cell-free Massive MIMO with ZF decoding we show that uplink power control is unnecessary, and that with 10 MHz effective bandwidth for uplink data transmission  ...  In rural morphology, using 450 MHz band, only 2 single antenna AP's per square kilometer is enough.  ...  Because high SINR is required, using Massive MIMO with MR decoding is in general not desirable.  ... 
arXiv:1902.04556v1 fatcat:h24e5dktyfeddnjjkzza5vk3nm

Performance Analysis of Self-Interference Cancellation in Full-Duplex Massive MIMO Systems: Subtraction versus Spatial Suppression [article]

Soo-Min Kim, Yeon-Geun Lim, Linglong Dai, Chan-Byoung Chae
2022 arXiv   pre-print
Accordingly, this paper presents a performance analysis of SI cancellation (SIC) methods in FD massive MIMO systems.  ...  One essential key to realizing practical FD massive MIMO systems is how to effectively mitigate the self-interference (SI).  ...  FD BS with Massive Arrays We consider FD multi-user MIMO channels, as illustrated in Fig. 1 , with a large number of antennas at the BS that serves K DL downlink users and K UL uplink users equipped with  ... 
arXiv:2205.14475v1 fatcat:lz5jw23xebdcfo4z4yspbw4ds4

Efficient Pilot Decontamination Schemes in 5G Massive MIMO Systems

Omar A. Saraereh, Imran Khan, Byung Moo Lee, Ashraf Tahat
2019 Electronics  
Aiming at the problem of pilot contamination in massive MIMO systems, this paper proposes two algorithms to mitigate it.  ...  users in each cell in a dynamic manner.  ...  Figure 1 . 1 Massive MIMO multi-cell multi-user TDD system model. Figure 1 . 1 Massive MIMO multi-cell multi-user TDD system model.  ... 
doi:10.3390/electronics8010055 fatcat:laauqc7wb5bntjdma7pm7xl6eq

Characterisation and Modelling of Measured Massive MIMO Channels [article]

Alex Oliveras Martinez
2017 PhD series, Technical Faculty of IT and Design, ˜Aalborg=ålborgœ University  
Gaussian models. User Multiplexing Massive MIMO is conceived as a multi-user MIMO system.  ...  The measurements are performed in highly realistic environments so the results are a good description of real massive MIMO implementations.  ...  Abstract A multi-user massive MIMO measurement campaign is conducted to study the channel propagation characteristics (e.g. user correlation, sum of eigenvalues and condition number), focusing on the stability  ... 
doi:10.5278/ fatcat:nv7beavwxvhehgu6prhticl7lm

Directional Spatial Channel Estimation For Massive FD-MIMO in Next Generation 5G Networks [article]

Ali A. Esswie, Octavia A. Dobre, Salama Ikki
2018 arXiv   pre-print
The proposed algorithm uses the statistical spatial correlation between the uplink (UL) and downlink (DL) channels of each user equipment.  ...  This letter proposes an FD-directional spatial channel estimation algorithm for frequency division duplex massive FD-MIMO systems.  ...  The proposed algorithm uses the statistical spatial correlation between the uplink (UL) and downlink (DL) channels of each user equipment.  ... 
arXiv:1806.03639v1 fatcat:4f6sjlzcgzawbfjmxlpkcl2qci

Interference-Nulling Time-Reversal Beamforming for mm-Wave Massive MIMO in Multi-User Frequency-Selective Indoor Channels [article]

Carlos A. Viteri-Mera, Fernando L. Teixeira
2015 arXiv   pre-print
In this paper, we analyze a baseband TR beamforming system for mm-wave multi-user massive MIMO.  ...  We use a 60 GHz MIMO channel model with spatial correlation based on the IEEE 802.11ad SISO NLoS model.  ...  In this section, we briefly describe the IEEE 802.11ad model for 60 GHz SISO systems in such scenarios [21] , and extend it to the correlated multi-user massive MIMO case.  ... 
arXiv:1506.05143v2 fatcat:zal3roik2jb4llm7h6fgln5wua

Massive MIMO Systems With Non-Ideal Hardware: Energy Efficiency, Estimation, and Capacity Limits

Emil Bjornson, Jakob Hoydis, Marios Kountouris, Merouane Debbah
2014 IEEE Transactions on Information Theory  
Recent works in the field of massive multiple-input multiple-output (MIMO) show that the user channels decorrelate when the number of antennas at the base stations (BSs) increases, thus strong signal gains  ...  Furthermore, we prove that the huge degrees of freedom offered by massive MIMO can be used to reduce the transmit power and/or to tolerate larger hardware impairments, which allows for the use of inexpensive  ...  ,b N using a negligible amount of overhead signaling [16] (even in massive MIMO systems [67] ).  ... 
doi:10.1109/tit.2014.2354403 fatcat:cla2u6vfordm5bhfavudmfe3d4

First Eigenmode Transmission by High Efficient CSI Estimation for Multiuser Massive MIMO Using Millimeter Wave Bands

Kazuki Maruta, Tatsuhiko Iwakuni, Atsushi Ohta, Takuto Arai, Yushi Shirato, Satoshi Kurosaki, Masataka Iizuka
2016 Sensors  
In Line-of-Sight (LoS) dominant channel environments, the first eigenmode is chiefly formed by the LoS component, which is highly correlated with user movement.  ...  Multiuser MIMO is also effective in further enhancing system capacity by multiplexing spatially de-correlated users.  ...  In other words, antenna elements in a UE are highly correlated to each other and this causes a large level gap between the 1st and 2nd eigenvalues in the LoS dominant single user MIMO channel.  ... 
doi:10.3390/s16071051 pmid:27399715 pmcid:PMC4970098 fatcat:4n4yypoquvew5abbvczqn2il2a

A Systematic Review on NOMA Variants for 5G and Beyond

Ishan Budhiraja, Neeraj Kumar, Sudhanshu Tyagi, Sudeep Tanwar, Zhu Han, Doug Young Suh, MD. Jalil Piran
2021 IEEE Access  
interference mitigation, resource allocations, and QoS management in the 5G environment.  ...  Over the last few years, interference has been a major hurdle for successfully implementing various end-user applications in the fifth-generation (5G) of wireless networks.  ...  Also, the authors in [249] provide the imperfect correlation in HB for multi-users.  ... 
doi:10.1109/access.2021.3081601 fatcat:mzmmr3km5zehhh3fnupyelfo3e

Hybrid NOMA for Future Radio Access: Design, Potentials and Limitations [article]

Kuntal Deka, Sanjeev Sharma
2020 arXiv   pre-print
Therefore, this article explores hybrid NOMA (HNOMA) for massive multiple access in the uplink scenarios due to its higher spectral efficiency.  ...  Non-orthogonal multiple access (NOMA) is a promising technology to address massive connectivity for 5G and beyond by accommodating several users within the same orthogonal resource block.  ...  EXAMPLE OF HNOMA-BASED SYSTEM IN UPLINK SCENARIO We show an example to achieve massive connectivity in IoT using the HNOMA.  ... 
arXiv:2012.08106v1 fatcat:53aqiu4oczbp3b55hmqkmt6o34

Toward 6G TKμ Extreme Connectivity: Architecture, Key Technologies and Experiments [article]

Xiaohu You, Yongming Huang, Shengheng Liu, Dongming Wang, Junchao Ma, Wei Xu, Chuan Zhang, Hang Zhan, Cheng Zhang, Jiao Zhang, Jin Li, Min Zhu (+12 others)
2022 arXiv   pre-print
A few most promising key technologies, i.e., cell-free massive MIMO, photonics-assisted Terahertz wireless access and spatiotemporal two-dimensional channel coding are further discussed.  ...  On this basis, a technological framework of pervasive multi-level (PML) AI is established in the centralised unit to enable task-centric near-real-time resource allocation and network automation.  ...  A cloud-based cell-free massive multiple-input multiple-output (MIMO) system was designed in [15] , in which the SE can exceed 100 bps/Hz.  ... 
arXiv:2208.01190v1 fatcat:3rq2ackzwjgkjhpo5j6osp7azq

Rate-Splitting Multiple Access: Fundamentals, Survey, and Future Research Trends [article]

Yijie Mao, Onur Dizdar, Bruno Clerckx, Robert Schober, Petar Popovski, H. Vincent Poor
2022 arXiv   pre-print
Compared to the conventional MA strategies used in 5G, RSMA enables spectral efficiency (SE), energy efficiency (EE), coverage, user fairness, reliability, and quality of service (QoS) enhancements for  ...  a wide range of network loads (including both underloaded and overloaded regimes) and user channel conditions.  ...  Cell-free massive MIMO usually assumes no instantaneous CSI sharing among users, and relies on the use of non-orthogonal uplink pilot sequences for channel estimation, which therefore results in pilot  ... 
arXiv:2201.03192v2 fatcat:z3ujjbqwxzc5dbgu3ganoqomae

Propagation Models and Performance Evaluation for 5G Millimeter-Wave Bands

Shu Sun, Ted Rappaport, Mansoor Shafi, Pan Tang, Jianhua Zhang, Peter J. Smith
2018 IEEE Transactions on Vehicular Technology  
This paper provides a comprehensive overview of the channel models that will likely be used in the design of 5G radio systems.  ...  Index Terms-Beamforming, channel models, coordinated multipoint (CoMP), hybrid beamforming, millimeter wave (mmWave), multiple-input multiple-output (MIMO), NYUSIM, fifth generation (5G).  ...  It also means that channel characteristics in closely located users are highly correlated.  ... 
doi:10.1109/tvt.2018.2848208 fatcat:43dj6bwrmnd37nf3xu4j6h3xz4

Scoring the Terabit/s Goal:Broadband Connectivity in 6G [article]

Nandana Rajatheva, Italo Atzeni, Simon Bicais, Emil Bjornson, Andre Bourdoux, Stefano Buzzi, Carmen D'Andrea, Jean-Baptiste Dore, Serhat Erkucuk, Manuel Fuentes, Ke Guan, Yuzhou Hu (+17 others)
2021 arXiv   pre-print
At the infrastructure level, we consider ultra-massive MIMO technology (possibly implemented using holographic radio), intelligent reflecting surfaces, user-centric cell-free networking, integrated access  ...  This paper explores the road to vastly improving the broadband connectivity in future 6G wireless systems. Different categories of use cases are considered, with peak data rates up to 1 Tbps.  ...  In 5G, massive MIMO has been the main drive to control co-user interference together with highly adaptive beamforming, which helps to serve the spatially separated users non-orthogonally by spatial multiplexing  ... 
arXiv:2008.07220v2 fatcat:k4yyvxjguzeqtgewy4bxmnmuo4
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