1. Massive MIMO in 5G
SEMINAR REPORT
Massive MIMO in 5G
EC451 : Seminar
Submitted By
RENJITHA M
(PKD16EC042)
under the guidance of
Lincy K
Asst.Professor, Dept.Of Electronics and Communication Engineering
DEPARTMENT OF ELECTRONICS AND COMMUNICATION
ENGINEERING
GOVERNMENT ENGINEERING COLLEGE SREEKRISHNAPURAM
PALAKKAD- 678633
Department of Electronics and communication engineering, Govt. Engg. College Palakkad i
2. Massive MIMO in 5G
CERTIFICATE
This is to certify that the report entitled Massive MIMO in 5G submitted by Renjitha M
to the Department of Electronics and Communication Engineering, Government Engineering
College, Sreekrishnapuram, Palakkad-678633, in fulfillment of the requirement for the award
of B-Tech Degree in Electronics and Communication Engineering, is a bonafide record of the
seminar carried out by her.
Prof. Shamla B Asst.Prof.Lincy K Dr. Mohanan K P
Co-ordinator Guide Head of the Department
Date:
Place: Sreekrishnapuram, Palakkad
Department of Electronics and communication engineering, Govt. Engg. College Palakkad ii
3. Massive MIMO in 5G
ACKNOWLEDGEMENT
First of all I thank the Almighty, for giving me strength ,courage and knowledge to do this
seminar successfully.
I express my heartfelt gratitude to the Principal Dr. P C Reghu Raj, Govt. Engineering
College, Sreekrishnapuram, for his inspiration throughout the seminar.
I would also like to thank Dr. Mohanan K P, Head Of the Department, Electronics and
Communication Engineering, Govt. Engineering College, Sreekrishnapuram for providing per-
mission and availing all required facilities for undertaking the seminar in a systematic way.
I am extremely grateful to Asst. Prof. Lincy K, my Internal Guide, Govt. Engineering
College, Sreekrishnapuram, who guided me with his kind, ordinal, valuable suggestions.
I would like to appreciate the guidance given by Prof.Shamla B, our Seminar Coordina-
tors, Department of Electronics and Communication Engineering, Govt. Engineering College,
Sreekrishnapuram, for providing sincere guidance.
I would also like to express my sincere gratitude to all teaching and non- teaching staffs
of Department of Electronics and Communication Engineering, Govt. Engineering College,
Sreekrishnapuram, for the sincere directions imparted and the cooperation in connection with
the seminar.
I am also thankful to my parents for the support given in connection with the seminar.
Gratitude may be extended to all well-wishers and my friends who supported me for the
seminar.
Department of Electronics and communication engineering, Govt. Engg. College Palakkad iii
4. Massive MIMO in 5G
ABSTRACT
5G technologies will change the way most high-bandwidth users access 5G supported phones.
With 5G pushed over a VOIP-enabled device, people will experience a level of call volume and
data transmission never experienced before.5G technology is offering the services in Product
Engineering, Documentation, supporting electronic transactions (e-Payments, e-transactions)
etc.NOVA was the first mobile operator to launch both 3G and 4G. NOVA expect 5G to be
widely adopted in Iceland in 2020,since they succeeded the 5G test recently. They used Massive
MIMO with router which essentially groups together antennas at the transmitter and receiver
to provide better throughput and better spectrum efficiency. The 5G design is based on user-
centric mobile environment with many wireless and mobile technologies on the ground. In
heterogeneous wireless environment changes in all, either new or older wireless technologies, is
not possible, so each solution towards the next generation mobile and wireless networks should
be implemented in the service stratum. In 5G technology the user terminal has possibility
to change the Radio Access Technology - RAT based on certain criteria. For the purpose of
transparent change of the RATs by the mobile terminal, routers are used, which establishes IP
tunnels to the mobile terminal via different available RATs to the terminal.
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6. CONTENTS Massive MIMO in 5G
5.0.2 Operation Mode of Massive MIMO . . . . . . . . . . . . . . . . . . . . . 25
5.0.3 Operational limits of Massive MIMO . . . . . . . . . . . . . . . . . . . . 26
5.0.4 Pilot Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
6 SCOPE AND APPLICATION 29
7 CONCLUSION 30
BIBLIOGRAPHY 31
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7. LIST OF FIGURES Massive MIMO in 5G
List of Figures
3.1 Functional Architecture of 5G Wireless . . . . . . . . . . . . . . . . . . . . . . . 16
4.1 MIMO in 4G Base station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
5.1 Massive MIMO in 5G . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.2 Uplink and Downlink operation of a MIMO link . . . . . . . . . . . . . . . . . . 26
5.3 Pilot Contamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
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8. Massive MIMO in 5G
Organisation of report The main body of the report is preceded by detailed contents
including abstract. This is followed by system description.
• Chapter 1 gives a brief introduction about the aim of the paper.
• Chapter 2 provides the literature survey.
• Chapter 3 provide overview and system architecture 5G Technology.
• Chapter 4 provides architecture of MIMO in LTE.
• Chapter 5 Discusses about the system architecture and opertion of Massive MIMO.
• Chapter 6 Discusses about future scope and benefits.
• Chapter 7 conclusion of the paper.
The main report is followed by references..
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9. Massive MIMO in 5G
Chapter 1
INTRODUCTION
Today phones have everything ranging from the smallest size, largest phone memory, speed
dialing, video player, audio player, and camera and so on. Recently with the development
of Pico nets and Blue tooth technology data sharing has become a child’s play. Earlier with
the infrared feature you can share data within a line of sight that means the two devices
has to be aligned properly to transfer data, but in case of blue tooth you can transfer data
even when you have the cell phone in your pocket up to a range of 50 meters. The creation
and entry of 5G technology into the mobile marketplace will launch a new revolution in the
way international cellular plans are offered. The global mobile phone is upon the cell phone
market. Just around the corner, the newest 5G technologies will hit the mobile market with
phones used in China being able to access and call locally phones in Germany.Truly innovative
technology changing the way mobile phones will be used. With the emergence of cell phones,
which are similar to a PDA, you can now have your whole office within the phone. Cell phones
will give tough competitions to laptop manufacturers and normal computer designers. Even
today there are phones with gigabytes of memory storage and the latest operating systems
.Thus one can say that with the current trends, the industry has a real bright future if it can
handle the best technologies and can produce affordable handsets for its customers. Thus you
will get all your desires unleashed in the near future when these smart phones take over the
market. 5G Network’s router and switch technology delivers Last Yard Connectivity between
the Internet access provider and building occupants. 5G’s technology intelligently distributes
Internet access to individual nodes within the building.
Cell phones are used millions and billions of users worldwide.0G , 1G, 2G, 3G 4G (”G”
stands for ”Generation”) are the generations of wireless telecom connectivity. In 1945, the
zero generation (0G) of mobile telephones was introduced. Mobile Telephone Service, were
not officially categorized as mobile phones, since they did not support the automatic change
of channel frequency during calls.1G (Time Division Multiple Access and Frequency Division
Multiple Access ) was the initial wireless telecom network system. It’s out-dated now. The
analog “brick phones” and “bag phones” are under 1G technology. Cell phones era began
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with 1G. The next era, 2G has taken its place of 1G. Cell phones received their first major
upgrade when they went from 1G to 2G. This leap effectively took cell phones from analog to
digital. 2G and 2.5G were versions of the GSM and CDMA connections. And GSM is still the
most popular technology, but with no internet. Fortunately, GPRS, an additional service, is
provided over GSM for the purpose of internet access. GPRS has been developed and thus,
EGPRS was created. It’s more secure and faster than GPRS.Then 3G came, the new Wireless
CDMA technology. It is the first wireless telecom technology that provides broadband-speed
internet connection on mobile phones. It has been specially made for the demand of internet
on smart phones. Further development led to the creation of 3.5G, which provides blazing
fast internet connection on phones, up to the speed of 7.2 MBPS. A smart phone can be
connected to a PC to share its internet connection and 3G and 3.5G are ideal for this. But,
as this WCDMA technology is not available in all regions, its not as popular as GSM yet.Next
comes 4G, which is also known as “beyond 3G” or “fourth-generation” cell phone technology,
refers to the entirely new evolution. Developers are now going for 4G (OFDMA), which will
provide internet up to the speed of 1 GBPS! It is said to be able to overcome the problems of
weak network strength and should provide a much wider network.making sure that the users get
high-speed connectivity anytime anywhere. No doubt, 4G will open new doors of revolutionary
internet technologies, but for now, 3G and 3.5G are the best. 4G will allow for speeds of up
to 100Mbps. 4G promises voice, data and high-quality multimedia in real-time form all the
timeand anywhere.
The use of MIMO technology has been introduced successively over the different releases
of the LTE standards.As the LTE standards progressed, so the numbers of antennas being
supported increased. For many mobiles the use of MIMO just resulted in improvements in signal
performance, whereas for others it was able to provide real data rate improvements.Recently,
massive MIMO technology has appealed to many researchers due to its promising capability of
greatly improving spectral efficiency, energy efficiency, and robustness of the system.Massive
MIMO is scalable to any desired degree with respect to the number of service antennas. Adding
more antennas is always beneficial for increased throughput, reduced radiated power, uniformly
great service everywhere in the cell, and greater simplicity in signal processing. Massive MIMO
is a brand new technology that has yet to be reduced to practice.
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Chapter 2
LITERATURE REVIEW
J.Hoydis S.ten Brink Massive MIMO in cellular networks IEEE vol.31, no.2, pp.160-171,
Feb.2018: Demand for wireless throughput, both mobile and fixed, will always increase. One
can anticipate that, in five or ten years, millions of augmented reality users in a large city will
want to transmit and receive 3D personal high-definition video more or less continuously, say
100 megabits per second per user in each direction. Massive MIMO-also called Large-Scale
Antenna Systems-is a promising candidate technology for meeting this demand. Fifty-fold or
greater spectral efficiency improvements over fourth generation (4G) technology are frequently
mentioned. A multiplicity of physically small, individually controlled antennas performs ag-
gressive multiplexing/demultiplexing for all active users, utilizing directly measured channel
characteristics. Unlike today’s Point-to-Point MIMO, by leveraging time-division duplexing
(TDD), Massive MIMO is scalable to any desired degree with respect to the number of ser-
vice antennas. Adding more antennas is always beneficial for increased throughput, reduced
radiated power, uniformly great service everywhere in the cell, and greater simplicity in signal
processing. Massive MIMO is a brand new technology that has yet to be reduced to practice.
Notwithstanding, its principles of operation are well understood, and surprisingly simple to
elucidate.
H. Q. Ngo, E. G. Larsson, and T. L. Marzetta, ”Energy and spectral efficiency
of very large multiuser MIMO systems, IEEE Trans. Commun., vol. 61, pp.
1436-1449, Apr. 2017: A multiplicity of autonomous terminals simultaneously transmits
data streams to a compact array of antennas. The array uses imperfect channel-state informa-
tion derived from transmitted pilots to extract the individual data streams. The power radiated
by the terminals can be made inversely proportional to the square-root of the number of base
station antennas with no reduction in performance. In contrast if perfect channel-state informa-
tion were available the power could be made inversely proportional to the number of antennas.
Lower capacity bounds for maximum-ratio combining (MRC), zeroforcing (ZF) and minimum
mean-square error (MMSE) detection are derived. An MRC receiver normally performs worse
than ZF and MMSE. However as power levels are reduced, the cross-talk introduced by the
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inferior maximum-ratio receiver eventually falls below the noise level and this simple receiver
becomes a viable option. The tradeoff between the energy efficiency (as measured in bits/J)
and spectral efficiency (as measured in bits/channel use/terminal) is quantified for a channel
model that includes small-scale fading but not large-scale fading. It is shown that the use of
moderately large antenna arrays can improve the spectral and energy efficiency with orders of
magnitude compared to a single-antenna system.
Patel, S., Chauhan, M., Kapadiya, 5G: Future mobile technology-vision 2020 In-
ternational Journal of Computer Applications: Currently, Mobile operators are busy
with deployment of 4G technology namely, LTE-advanced or WIMAX 802.16m. This 4G tech-
nology will be concluded within two years. 5G technology is not standardizing yet, probably
5G standard will define in two to three years, and its deployment will start around 2020. In
future, people will expect same quality of internet connectivity as the device is capable. This
technology will include all types of advanced features, which make 5G technology more power-
ful. The main features we want to add in 5G mobile network is that user can simultaneously
connect to the multiple wireless technologies and can switch between them. Forthcoming mo-
bile technology has to support IPv6 and flat IP. This paper explains different technology which
we want to include making future mobile technology more powerful and more in demand.
T. S. Rappaport, Shu Sun, Rimma Mayzual ‘Millimeter wave mobile communi-
cations for 5G cellular roc. IEEE, vol. 1, 2013, no. 10, pp. 335349, may. 2013:
The global bandwidth shortage facing wireless carriers has motivated the exploration of the
underutilized millimeter wave (mm-wave) frequency spectrum for future broadband cellular
communication networks. There is, however, little knowledge about cellular mm-wave propa-
gation in densely populated indoor and outdoor environments. Obtaining this information is
vital for the design and operation of future flufth generation cellular networks that use the mm-
wave spectrum. In this paper, we present the motivation for new mm-wave cellular systems,
methodology, and hardware for measurements and offer a variety of measurement results that
show 28 and 38 GHz frequencies can be used when employing steerable directional antennas
at base stations and mobile devices.
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Chapter 3
5G TECHNOLOGY
5G Technology stands for 5th Generation Mobile technology. 5G technology has changed
the means to use cell phones within very high bandwidth. User never experienced ever before
such a high value technology.The 5G technologies include all type of advanced features which
makes 5G technology most powerful and in huge demand in near future.The gigantic array of
innovative technology being built into new cell phones is stunning. 5G technologies which are
on hand held phone offering more power and features than at least 1000 lunar modules. A
user can also hook their 5G technology cell phone with their Laptop to get broadband internet
access. 5G technology including camera, MP3 recording, video player, large phone memory,
dialling speed, audio player and much more you never imagine.
5G technology going to be a new mobile revolution in mobile market . Through 5G technology
now you can use worldwide cellular phones and this technology also strike the china mobile
market and a user being proficient to get access to Germany phone as a local phone. With the
coming out of cell phone alike to PDA now your whole office in your finger tips or in your phone.
5G technology has extraordinary data capabilities and has ability to tie together unrestricted
call volumes and infinite data broadcast within latest mobile operating system. 5G technology
has a bright future because it can handle best technologies and offer priceless handset to their
customers. May be in coming days 5G technology takes over the world market. 5G Technologies
have an extraordinary capability to support Software and Consultancy. The Router and switch
technology used in 5G network providing high connectivity. The 5G technology distributes
internet access to nodes within the building and can be deployed with union of wired or
wireless network connections. The current trend of 5G technology has a glowing future.
5G technology offer high resolution for crazy cell phone user and bi-directional large band-
width shaping.The advanced billing interfaces of 5G technology makes it more attractive and
effective.5G technology also providing subscriber supervision tools for fast action.The high
quality services of 5G technology based on Policy to avoid error.5G technology is providing
large broadcasting of data in Gigabit which supporting almost 65,000 connections and offer
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transporter class gateway with unparalleled consistency.Also traffic statistics by 5G technology
makes it more accurate.
3.0.1 5G Spectrum and Deployement
Large quantities of new radio spectrum (5G NR frequency bands) have been allocated to
5G in order to enable its increased throughput when compared with 4G. For example, in
July 2016, the U.S. Federal Communications Commission (FCC) freed up vast amounts of
bandwidth in underused high-band spectrum for 5G. The Spectrum Frontiers Proposal (SFP)
doubled the amount of millimeter-wave unlicensed spectrum to 14 GHz and created four times
the amount of flexible, mobile-use spectrum the FCC had licensed to date.In March 2018,
European Union lawmakers agreed to open up the 3.6 and 26 GHz bands by 2020.As of March
2019, there are reportedly 52 countries, territories, special administrative regions, disputed
territories and dependencies that are formally considering introducing certain spectrum bands
for terrestrial 5G services, are holding consultations regarding suitable spectrum allocations for
5G, have reserved spectrum for 5G, have announced plans to auction frequencies or have already
allocated spectrum for 5G use. Research has been done into the most suitable candidates
for spectrum ranges for 5G.Due to the demand for spectrum resources and wide frequency
range of 5G technology, it is necessary to plan high, medium and low frequency bands in
stages in frequency planning, gradually release frequency resources and guarantee the frequency
requirements of 5G.The frequency spectrum became a focus due to predictions that the 3G/4G
frequency spectrum would not suffice to accommodate the amount of traffic that 5G will need
to handle.
Beyond mobile operator networks, 5G is also expected to be widely used for private networks
with applications in industrial IoT, enterprise networking, and critical communications.Initial
5G NR launches will depend on existing LTE (4G) infrastructure in non-standalone (NSA)
mode (5G NR software on LTE radio hardware), before maturation of the standalone (SA)
mode (5G NR software on 5G NR radio hardware) with the 5G core network.As of April
2019, the Global Mobile Suppliers Association had identified 224 operators in 88 countries
that are actively investing in 5G (i.e. that have demonstrated, are testing or trialling, or have
been licensed to conduct field trials of 5G technologies, are deploying 5G networks or have
announced service launches).The equivalent numbers in November 2018 were 192 operators in
81 countries.The first country to adopt 5G on a large scale was South Korea, in April 2019.
When South Korea launched its 5G network, all carriers used Samsung, Ericsson, and Nokia
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base stations and equipment, except for LG U Plus, who also used Huawei equipment.Samsung
was the largest supplier for 5G base stations in South Korea at launch, having shipped 53,000
base stations at the time, out of 86,000 base stations installed across the country at the time.
he first fairly substantial deployments were in April 2019. In South Korea, SK Telecom claimed
38,000 base stations, KT Corporation 30,000 and LG U Plus 18,000; of which 85 percent are
in six major cities.They are using 3.5 GHz (sub-6) spectrum in non-standalone (NSA) mode
and tested speeds were from 193 to 430 Mbit/s down. 260,000 signed up in the first month
and the goal is 10 percent of phones on 5G by the end of 2019.
3.0.2 Emerging Features of 5G
New radio frequencies: The air interface defined by 3GPP for 5G is known as New Radio
(NR), and the specification is subdivided into two frequency bands, FR1 (below 6 GHz) and
FR2 (mmWave),each with different capabilities.
Frequency range 1 (less than 6 GHz): The maximum channel bandwidth defined for
FR1 is 100 MHz, due to the scarcity of continuous spectrum in this crowded frequency range.
The band most widely being used for 5G in this range is around 3.5 GHz. The Korean carriers
are using 3.5 GHz although some millimeter wave spectrum has also been allocated.
Frequency range 2 (greater than 24 GHz): The minimum channel bandwidth defined
for FR2 is 50 MHz and the maximum is 400 MHz, with two-channel aggregation supported in
3GPP Release 15. In the U.S., Verizon is using 28 GHz and ATT is using 39 GHz. 5G can
use frequencies of up to 300 GHz.The higher the frequency, the greater the ability to support
high data transfer speeds without interfering with other wireless signals or becoming overly
cluttered. Due to this, 5G can support approximately 1,000 more devices per meter than 4G.
FR2 coverage: 5G in the 24 GHz range or above use higher frequencies than 4G, and as a
result, some 5G signals are not capable of traveling large distances (over a few hundred meters),
unlike 4G or lower frequency 5G signals (sub 6 GHz). This requires placing 5G base stations
every few hundred meters in order to use higher frequency bands. Also, these higher frequency
5G signals cannot penetrate solid objects easily, such as cars, trees, and walls, because of the
nature of these higher frequency electromagnetic waves.
Massive MIMO: Massive MIMO (multiple input and multiple output) antennas increases
sector throughput and capacity density using large numbers of antennas and Multi-user MIMO
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(MU-MIMO). Each antenna is individually-controlled and may embed radio transceiver com-
ponents. Nokia claimed a five-fold increase in the capacity increase for a 64-Tx/64-Rx antenna
system. The term ”massive MIMO” was coined by Nokia Bell Labs researcher Dr. Thomas L.
Marzetta in 2010, and has been launched in 4G networks, such as Softbank in Japan.
Edge computing: Edge computing is delivered by cloud computing servers closer to the
ultimate user. It reduces latency and data traffic congestion.
Small cell: Small cells are low-powered cellular radio access nodes that operate in licensed
and unlicensed spectrum that have a range of 10 meters to a few kilometers. Small cells are
critical to 5G networks, as 5G’s radio waves can’t travel long distances, because of 5G’s higher
frequencies.
Beamforming: Beamforming, as the name suggests, is used to direct radio waves to a tar-
get. This is achieved by combining elements in an antenna array in such a way that signals
at particular angles experience constructive interference while others experience destructive
interference. This improves signal quality and data transfer speeds. 5G uses beamforming due
to the improved signal quality it provides. Beamforming can be accomplished using Phased
array antennas.
Wifi-cellular convergence: One expected benefit of the transition to 5G is the convergence
of multiple networking functions to achieve cost, power, and complexity reductions. LTE has
targeted convergence with Wi-Fi band/technology via various efforts, such as License Assisted
Access (LAA; 5G signal in unlicensed frequency bands that are also used by Wi-Fi) and LTE-
WLAN Aggregation (LWA; convergence with Wi-Fi Radio), but the differing capabilities of
cellular and Wi-Fi have limited the scope of convergence. However, significant improvement
in cellular performance specifications in 5G, combined with migration from Distributed Radio
Access Network (D-RAN) to Cloud- or Centralized-RAN (C-RAN) and rollout of cellular small
cells can potentially narrow the gap between Wi-Fi and cellular networks in dense and indoor
deployments. Radio convergence could result in sharing ranging from the aggregation of cellular
and Wi-Fi channels to the use of a single silicon device for multiple radio access technologies.
Operation in unlicensed spectrum: Like LTE in unlicensed spectrum, 5G NR will also
support operation in unlicensed spectrum (NR-U).In addition to License Assisted Access (LAA)
from LTE that enable carriers to use those unlicensed spectrum to boost their operational
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performance for users, in 5G NR it will support standalone NR-U unlicensed operation that
will allow new 5G NR networks to be established in different environments without acquiring
operational license in licensed spectrum, for instance for localized private network or lower the
entry barrier for providing 5G internet services to the public.
3.0.3 5G Core Architecture
The 5G core network architecture is at the heart of the new 5G specification and enables the
increased throughput demand that 5G must support. The new 5G core, as defined by 3GPP,
utilizes cloud-aligned, service-based architecture (SBA) that spans across all 5G functions and
interactions including authentication, security, session management and aggregation of traffic
from end devices. The 5G core further emphasizes NFV as an integral design concept with
virtualized software functions capable of being deployed using the MEC infrastructure that
is central to 5G architectural principles.Changes at the core level are among the myriad of
architectural changes that accompany the shift from 4G to 5G, including the migration to
millimeter wave, massive MIMO, network slicing and essentially every other discrete element
of the diverse 5G ecosystem. The 4G Evolved Packet Core (EPC) is significantly different
from the 5G core, with the 5G core leveraging virtualization and cloud native software design
at unprecedented levels. Among the other changes that differentiate the 5G core from its
4G predecessor are user plane function (UPF) to decouple packet gateway control and user
plane functions, and access and mobility management function (AMF) to segregate session
management functions from connection and mobility management tasks.
ridging the gap between 4G and 5G will require incremental steps and a well-orchestrated
game plan. Emblematic of this shift will be the gradual transition from stand-alone mode to
non-standalone mode 5G architecture options. The 5G non-standalone standard was finalized
in late 2017 and utilizes existing LTE radio access and core networks as an anchor, with the ad-
dition of a 5G component carrier. Despite the reliance on existing architecture, non-standalone
mode will increase bandwidth by tapping into millimeter wave frequencies.5G standalone mode
is essentially 5G deployment from the ground up with the new core architecture and full deploy-
ment of all 5G hardware, features and functionality. As non-standalone mode gradually gives
way to new 5G mobile network architecture deployments, careful planning and implementation
will make this transition seamless for the user base.
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3.0.4 Functional Architecture
The system consists of a user terminal (which has a crucial role in the new architecture) and
a number of independent, autonomous radio access technologies. Within each of the terminals,
each of the radio access technologies is seen as the IP link to the outside Internet world.
However, there should be different radio interface for each Radio Access Technology (RAT) in
the mobile terminal. For an example, if we want to have access to four different RATs, we
need to have four different access - specific interfaces in the mobile terminal, and to have all of
them active at the same time, with aim to have this architecture to be functional applications
and servers somewhere on the Internet. Routing of packets should be carried out in accordance
with established policies of the user.
Application connections are realized between clients and servers in the Internet via sockets.
Internet sockets are endpoints for data communication flows. Each socket of the web is a unified
and unique combination of local IP address and appropriate local transport communications
port, target IP address and target appropriate communication port, and type of transport
protocol. Considering that, the establishment of communication from end-to-end between the
client and server using the Internet protocol is necessary to raise the appropriate Internet
socket uniquely determined by the application of the client and the server. This means that in
case of interoperability between heterogeneous networks and for the vertical handover between
the respective radio technologies, the local IP address and destination IP address should be
fixed and unchanged. Fixing of these two parameters should ensure handover transparency
to the Internet connection end-to-end, when there is a mobile user at least on one end of
such connection. In order to preserve the proper layout of the packets and to reduce or prevent
packets losses, routing to the target destination and vice versa should be uniquely and using the
same path. Each radio access technology that is available to the user in achieving connectivity
with the relevant radio access is presented with appropriate IP interface. Each IP interface in
the terminal is characterized by its IP address and net mask and parameters associated with
the routing of IP packets across the network.
In regular inter-system handover the change of access technology (i.e., vertical handover)
would mean changing the local IP address. Then, change of any of the parameters of the
socket means and change of the socket, that is, closing the socket and opening a new one.
This means, ending the connection and starting e new one. This approach is not-flexible, and
it is based on today’s Internet communication. In order to solve this deficiency we propose
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Figure 3.1: Functional Architecture of 5G Wireless
a new level that will take care of the abstraction levels of network access technologies to
higher layers of the protocol stack. This layer is crucial in the new architecture. To enable the
functions of the applied transparency and control or direct routing of packets through the most
appropriate radio access technology, in the proposed architecture we introduce a control system
in the functional architecture of the networks, which works in complete coordination with the
user terminal and provides a network abstraction functions and routing of packets based on
defined policies.The network abstraction level would be provided by creating IP tunnels over
IP interfaces obtained by connection to the terminal via the access technologies available to
the terminal.In fact, the tunnels would be established between the user terminal and control
system named here as Policy Router, which performs routing based on given policies. In this
way the client side will create an appropriate number of tunnels connected to the number of
radio access technologies, and the client will only set a local IP address which will be formed
with sockets Internet communication of client applications with Internet servers. The way IP
packets are routed through tunnels, would be served by policies whose rules will be exchanged
via the virtual network layer protocol. This way we achieve the required abstraction of the
network to the client applications at the mobile terminal. The process of establishing a tunnel
to the Policy Router, for routing based on the policies, are carried out immediately after the
establishment of IP connectivity across the radio access technology, and it is initiated from
the mobile terminal Virtual Network-level Protocol. Establishing tunnel connections as well as
maintaining them represents basic functionality of the virtual network level.
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3.0.5 Challenges for Implementing 5G network
Interference issues: Spectrum used by various 5G proposals will be near that of passive
remote sensing such as by weather and Earth observation satellites, particularly for water
vapor monitoring. Interference will occur and will potentially be significant without effective
controls. An increase in interference already occurred with some other prior proximate band
usages.Interference to satellite operations impairs numerical weather prediction performance
with substantially deleterious economic and public safety impacts.The concerns prompted U.S.
Secretary of Commerce Wilbur Ross and NASA Administrator Jim Bridenstine in February
2019 to urge the FCC to delay some spectrum auction proposals, which was rejected.The
chairs of the House Appropriations Committee and House Science Committee wrote separate
letters to FCC chair Ajit Pai asking for further review and consultation with NOAA, NASA,
and DoD, and warning of harmful impacts to national security.Acting NOAA director Neil
Jacobs testified before the House Committee in May 2019 that 5G out-of-band emissions could
produce a 30 percent reduction in weather forecast accuracy and that the resulting degradation
in ECMWF model performance would have failed to predict the track and thus, the impact
of Superstorm Sandy in 2012. The United States Navy in March 2019 wrote a memorandum
warning of deterioration and made technical suggestions to control band bleed-over limits, for
testing and fielding, and for coordination of the wireless industry and regulators with weather
forecasting organizations.
Surveillance concerns: Due to fears of potential espionage of foreign users by Chinese
equipment vendors, several countries (including Australia and the United Kingdom as of early
2019)have taken actions to restrict or eliminate the use of Chinese equipment in their respective
5G networks. Chinese vendors and the Chinese government have denied these claims.In 2019,
the United States via its FBI, the British GCHQ, other intelligence agencies, and criminal
prosecuting organizations, is heavily involved in adjusting surveillance standards. The 5G
security architecture is being adjusted so as much metadata as possible is collected for mass
surveillance purposes. This happens via the 3SALI meetings of the 3GPP standardization
organization.
Health concerns: The development of the technology has elicited a range of responses re-
garding concerns that 5G radiation could have adverse health effects.An article in the scientific
magazine Scientific American emphasized that scientific research regarding its effects have
not been conducted and that there could be health risks.Wired characterized fears that the
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21. Massive MIMO in 5G
technology could cause cancer, infertility, autism, Alzheimer’s, and mysterious bird deaths as
”conspiracy theory”.In April 2019, the city of Brussels in Belgium blocked a 5G trial because
of radiation laws.In Geneva, Switzerland, a planned upgrade to 5G was stopped for the same
reason.The Swiss Telecommunications Association (ASUT) has said that studies have been
unable to show that 5G frequencies have any health impact.Health concerns related to radi-
ation from cell telephone towers and cell telephones are not new. Although electromagnetic
hypersensitivity is not scientifically recognized, effects such as headaches and neurasthenia have
been claimed from 4G and Wi-Fi. However, 5G technology presents a couple of new issues that
depart from 4G technology, namely, higher microwave frequencies from 2.6 GHz to 28 GHz,
compared to 700–2500 MHz typically used by 4G.
Because the higher millimeter wave used in 5G does not penetrate objects easily, this
requires the installation of antennas every few hundred meters, which has sparked concern
among the public.Critics of 5G say that these millimeter wavelengths have not been tested
extensively on the general public. Most experts believe that more scientific research is needed,as
even though millimeter wave technology has been used in technology such as radar for many
decades,there is considerable research regarding the association of cancer to the use of radar
devices by police officers.
Security concerns: n 18 October 2018, a team of researchers from ETH Zurich, the Uni-
versity of Lorraine and the University of Dundee released a paper entitled, “A Formal Analysis
of 5G Authentication”.It alerted that 5G technology could open ground for a new era of se-
curity threats. The paper described the technology as “immature and insufficiently tested,”
the one that “enables the movement and access of vastly higher quantities of data, and thus
broadens attack surfaces”. Simultaneously, network security companies such as Fortinet,Arbor
Networks,A10 Networks,and Voxility advised on personalized and mixed security deployments
against massive DDoS attacks foreseen after 5G deployment.
IoT Analytics estimated an increase in the number of IoT devices, enabled by 5G technology,
from 7 billion in 2018 to 21.5 billion by 2025.This can raise the attack surface for these devices
to a substantial scale, and the capacity for DDoS attacks, cryptojacking, and other cyberattacks
could boost proportionally.
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Chapter 4
MIMO IN 4G BASE STATION
In radio, multiple-input and multiple-output, or MIMO is a method for multiplying the ca-
pacity of a radio link using multiple transmission and receiving antennas to exploit multipath
propagation.MIMO has become an essential element of wireless communication standards in-
cluding IEEE 802.11n (Wi-Fi), IEEE 802.11ac (Wi-Fi), HSPA+ (3G), WiMAX (4G), and Long
Term Evolution (4G LTE). More recently, MIMO has been applied to power-line communica-
tion for 3-wire installations as part of ITU G.hn standard and HomePlug AV2 specification.At
one time, in wireless the term ”MIMO” referred to the use of multiple antennas at the trans-
mitter and the receiver. In modern usage, ”MIMO” specifically refers to a practical technique
for sending and receiving more than one data signal simultaneously over the same radio channel
by exploiting multipath propagation. MIMO is fundamentally different from smart antenna
techniques developed to enhance the performance of a single data signal, such as beamforming
and diversity.
MIMO, Multiple Input Multiple Output is a technology that was introduced into many
wireless communications systems including 4G LTE to improve the signal performance.Using
multiple antennas, LTE MIMO is able to utilise the multiple path propagation that exists to
provide improvements in signal performance.LTE MIMO adds complexity to the system, but
it is able to provide some significant improvements in performance and spectral efficiency and
these more than justify its inclusion in the LTE standard.The use of MIMO technology has
been introduced successively over the different releases of the LTE standards.MIMO has been
a cornerstone of the LTE standard, but initially, in releases 8 and 9 multiple transmit antennas
on the UE was not supported because in the interested of power reduction, only a single RF
power amplifier was assumed to be available.As the LTE standards progressed, so the numbers
of antennas being supported increased. For many mobiles the use of MIMO just resulted in
improvements in signal performance, whereas for others it was able to provide real data rate
improvements.
A 4G base station can only handle a certain number of calls at one time. A typical base
station has about 168 voice channels available and once capacity is nearly reached the base
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23. Massive MIMO in 5G
Figure 4.1: MIMO in 4G Base station
station will seamlessly hand off a mobile user to another base station within the users range.The
base station will also have a limit to the amount of bandwidth available for internet and data
use. With the introduction of smart phones, the carriers have had to increase the channel
bandwidth and base stations to ensure the internet does not become slow during peak periods.
The wider the channel bandwidth, the wider the pipe is to send data. Standard channel
bandwidths used by the carriers in Australia are 10 MHz or 15 MHz. Vodafone plan on using
20MHz of bandwidth for 4G.And the cell coverage area is determined by the base station
output power and the environment. Things such trees, hills, buildings and land formations will
have an affect on the coverage area.In city areas there is generally a larger number of users and
also obstructions.
4.0.1 LTE MIMO Modes
There are several ways in which MIMO is implemented in LTE. These vary according to the
equipment used, the channel function and the equipment involved in the link.
i.Single antenna: This is the form of wireless transmission used on most basic wireless links.
A single data stream is transmitted on one antenna and received by one or more antennas.
It may also be referred to as SISO: Single In Single Out or SIMO Single In Multiple Out
dependent upon the antennas used. SIMO is also called receive diversity.
ii.Transmit diversity: This form of LTE MIMO scheme utilises the transmission of the same
information stream from multiple antennas. LTE supports two or four for this technique.. The
information is coded differently using Space Frequency Block Codes. This mode provides an
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24. Massive MIMO in 5G
improvement in signal quality at reception and does not improve the data rate. Accordingly
this form of LTE MIMO is used on the Common Channels as well as the Control and Broadcast
channels.
iii.Open loop spatial multiplexing: This form of MIMO used within the LTE system
involves sending two information streams which can be transmitted over two or more anten-
nas. However there is no feedback from the UE although a TRI, Transmit Rank Indicator
transmitted from the UE can be used by the base station to determine the number of spatial
layers.
iv.Close loop spatial multiplexing: This form of LTE MIMO is similar to the open loop
version, but as the name indicates it has feedback incorporated to close the loop. A PMI,
Pre-coding Matrix Indicator is fed back from the UE to the base station. This enables the
transmitter to pre-code the data to optimise the transmission and enable the receiver to more
easily separate the different data streams.
v.Closed loop with pre-coding: This is another form of LTE MIMO, but where a single
code word is transmitted over a single spatial layer. This can be sued as a fall-back mode for
closed loop spatial multiplexing and it may also be associated with beamforming as well.
vi.Multi-User MIMO, MU-MIMO: This form of LTE MIMO enables the system to target
different spatial streams to different users.
vii.Beam-forming MIMO: This is the most complex of the MIMO modes and it is likely
to use linear arrays that will enable the antenna to focus on a particular area. This will reduce
interference, and increase capacity as the particular UE will have a beam formed in their
particular direction. In this a single code word is transmitted over a single spatial layer. A
dedicated reference signal is used for an additional port. The terminal estimates the channel
quality from the common reference signals on the antennas.
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4.0.2 Functions of LTE MIMO
MIMO can be sub-divided into three main categories: precoding, spatial multiplexing (SM),
and diversity coding.
Precoding: It is multi-stream beamforming, in the narrowest definition. In more general
terms, it is considered to be all spatial processing that occurs at the transmitter. In (single-
stream) beamforming, the same signal is emitted from each of the transmit antennas with
appropriate phase and gain weighting such that the signal power is maximized at the receiver
input. The benefits of beamforming are to increase the received signal gain – by making signals
emitted from different antennas add up constructively – and to reduce the multipath fading
effect. In line-of-sight propagation, beamforming results in a well-defined directional pattern.
However, conventional beams are not a good analogy in cellular networks, which are mainly
characterized by multipath propagation.
Spacial Multiplexing: requires MIMO antenna configuration. In spatial multiplexing,a
high-rate signal is split into multiple lower-rate streams and each stream is transmitted from a
different transmit antenna in the same frequency channel. If these signals arrive at the receiver
antenna array with sufficiently different spatial signatures and the receiver has accurate CSI,
it can separate these streams into (almost) parallel channels. Spatial multiplexing is a very
powerful technique for increasing channel capacity at higher signal-to-noise ratios (SNR). The
maximum number of spatial streams is limited by the lesser of the number of antennas at the
transmitter or receiver. Spatial multiplexing can be used without CSI at the transmitter, but
can be combined with precoding if CSI is available. Spatial multiplexing can also be used
for simultaneous transmission to multiple receivers, known as space-division multiple access or
multi-user MIMO, in which case CSI is required at the transmitter.
Diversity coding: techniques are used when there is no channel knowledge at the trans-
mitter. In diversity methods, a single stream (unlike multiple streams in spatial multiplexing)
is transmitted, but the signal is coded using techniques called space-time coding. The signal
is emitted from each of the transmit antennas with full or near orthogonal coding. Diversity
coding exploits the independent fading in the multiple antenna links to enhance signal diversity.
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Chapter 5
MASSIVE MIMO IN 5G
Multiple-antenna (MIMO) technology is becoming mature for wireless communications and
has been incorporated into wireless broadband standards like LTE and Wi-Fi. Basically, the
more antennas the transmitter/receiver is equipped with, the more the possible signal paths
and the better the performance in terms of data rate and link reliability. The price to pay is
increased complexity of the hardware (number of RF amplifier frontends) and the complexity
and energy consumption of the signal processing at both ends.Massive MIMO (also known
as Large-Scale Antenna Systems, Very Large MIMO, Hyper MIMO, Full-Dimension MIMO
and ARGOS) makes a clean break with current practice through the use of a very large num-
ber of service antennas (e.g., hundreds or thousands) that are operated fully coherently and
adaptively. Extra antennas help by focusing the transmission and reception of signal energy
into ever-smaller regions of space. This brings huge improvements in throughput and energy
efficiency, in particularly when combined with simultaneous scheduling of a large number of
user terminals (e.g., tens or hundreds). Massive MIMO was originally envisioned for time divi-
sion duplex (TDD) operation, but can potentially be applied also in frequency division duplex
(FDD) operation.In TDD mode uplink and downlink tranfer occur on same radio frequency ie,
only one channel is required.So the chammel noise in Massive MIMO is less.Where as in FDD
mode two channel is required for this two tranfer.
5.0.1 Constuction of Massive MIMO
Massive MIMO, as you might guess, takes MIMO technology and scales it up to hundreds
or even thousands of antennas and terminals. These antennas, attached to a base station,
focus the transmission and reception of signal energy into small regions of space, providing
new levels of efficiency and throughput. The more antennas that are used, the finer the spatial
focusing can be.In massive MIMO antennas can be used to increase the gain of transmitted
signals. This means they radiate less power when transmitting data that makes more energy
efficient system. A Massive MIMO network is a multicarrier cellular network with L cells that
operate according to asynchronous TDD protocol. A synchronous TDD protocol refers to a
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27. Massive MIMO in 5G
Figure 5.1: Massive MIMO in 5G
protocol in which UL and DL transmissions within different cells are synchronized. In massive
MIMO the BS is equipped with M antennas to serve K number of users in each cell and M K
.Massive MIMO is also known by other names such as ”Large Scale Antenna Systems”, ”Hyper
MIMO”, ”Very Large MIMO”, ”ARGOS” and ”Full Dimension MIMO”. The antenna arrays
have attractive form factors: in the 2 GHz band, a halfwavelength-spaced rectangular array
with 200 dual-polarized elements is about 1.5 x 0.75 meters large. Massive MIMO operates in
TDD mode and the downlink beamforming exploits the uplink-downlink reciprocity of radio
propagation. Specifically, the base station array uses channel estimates obtained from uplink
pilots transmitted by the terminals to learn the channel in both directions. This makes Massive
MIMO entirely scalable with respect to the number of base station antennas. Base stations
in Massive MIMO operate autonomously, with no sharing of payload data or channel state
information with other cells. Massive MIMO has many advantages compared to conventional
MIMO systems.
Lots of channel measurements have been carried out in order to discriminate the main prop-
erties of massive MIMO channel. These measurements mainly focus on the impacts of antenna
numbers on the small-scale propagation characteristics. Further measurements should be im-
plemented to validate the two properties for the spherical, cylindrical, and rectangular antenna
array configurations. Channel measurements for both the cylindrical and linear antenna array
with 128-antenna were implemented, when the space of adjacent antennas is half a wavelength
and the bandwidth is 50MHz. Similar to, the non-stationary phenomenon can be observed
over the linear antenna array. Meanwhile, large power variation can also be experienced over
the cylindrical antenna array as of both the polarization and directional pattern.
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5.0.2 Operation Mode of Massive MIMO
A non-stationary wireless channel needs to be re-estimated after every coherence time lap.
Massive MIMO systems were originally envisioned for time division duplex (TDD) operation,
in which the channel is periodically estimated in one direction and compensation can be applied
in both directions assuming reciprocity.
TDD systems have the following features:
1. The time required to acquire CSI does not depend on the number of BSs or users.
2. Only the BS needs to know the information about the channels to process antennas
coherently.
In TDD systems, multi-user precoding in the downlink and detection in the uplink require
CSI knowledge at the BS. The resource, time or frequency needed for channel estimation is
proportional to the number of the transmit antennas. In frequency division duplexing (FDD),
uplink and downlink use different frequency bands (different CSI in both links). The uplink
channel estimation at the BS is done by letting all users send different pilot sequences. To
get the CSI for the downlink channel, the BS transmits pilot symbols to all users. The users
respond by the estimated CSI for the downlink channels. CSI can be estimated at the receiver
side only, or at both at the transmitter and the receiver. Estimation at both sides has some
advantages. The CSI does not have to be transmitted, which yields low latency and high
capacity. In addition, more power can be allocated to the (OFDM) subchannels with higher
channel gain. Schemes with estimation at the receiver side only experience higher outage
probability with fast fading channels but have lower complexity.
As the number of BS antennas goes up, the time required to transmit the downlink pilot
symbols increases. In addition, as the number of BS antennas grows, FDD channel estimation
becomes almost impossible and a TDD approach can resolve this issue. In TDD systems, due
to channel reciprocity, only CSI for the uplink needs to be estimated. In addition, linear MMSE
based channel estimation can provide near-optimal performance with low complexity.
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29. Massive MIMO in 5G
Figure 5.2: Uplink and Downlink operation of a MIMO link
5.0.3 Operational limits of Massive MIMO
MIMO is already found on some 4G base stations. But so far, massive MIMO has only
been tested in labs and a few field trials,beause Massive MIMO comes with its own compli-
cation. Ie, broadcasting many more Information in every direction at once, And all these
crossing signals cause serious interference.Deploying a system with hundreds or thousands of
antennas and terminals requires more advanced processing capability in the nodes. Also, each
node must be able to determine the data transmitted from one antenna to th another, other-
wise network performance will be limited.This requires sophisticated channel estimation and
sounding techniques.Also making many low-cost low-precision components that work effec-
tively together.Acquisition and synchronization for newly joined terminals and exploitation of
extra degrees of freedom provided by the excess of service antennas and finding new deploy-
ment scenarios is quite difficult.Reducing internal power consumption to achieve total energy
efficiency reductions is a challenge.Massive MIMO have igh signal processing complexity due
to utilization of large number of antennas and multiplexing of UEs and also sensitive to beam
alignment, as extremely narrower beam is used which is sensitive to movement of MS or swaying
of antenna array.
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30. Massive MIMO in 5G
5.0.4 Pilot Contamination
As wireless communications systems have to accommodate an ever-increasing number of data
transfers,but a lack of sufficient protocols for ensuring that data is transferred to the correct
user could leave systems open to an attack.To address this issue, smaller, periodic signals called
pilots are assigned to each user, which ensure that data is transferred to the correct person. A
major constraint of this approach is that limited number of piolts are available, but the number
of communication channels in base stations are growing. Sometimes, users must be assigned
the same pilot sequence, which can interfere with the proper transfer of data and lead to poor
system performance. This is called pilot contamination.When an attacker is close to the base
station, within 300 meters or closer, he or she can impose their own pilots strongly enough to
reduce the total transmission rate of a massive MIMO system by more than 50 percent.
The base station wants to know the channel responses of its user terminals and these are
estimated in the uplink by sending pilot signals. Each pilot signal is corrupted by inter-cell
interference and noise when received at the base station. For example, consider the scenario
illustrated below where two terminals are transmitting simultaneously, so that the base station
receives a superposition of their signals—that is, the desired pilot signal is contaminated.When
estimating the channel from the desired terminal, the base station cannot easily separate the
signals from the two terminals. This has two key implications:First, the interfering signal
acts as colored noise that reduces the channel estimation accuracy.Second, the base station
unintentionally estimates a superposition of the channel from the desired terminal and from
the interferer. Later, the desired terminal sends payload data and the base station wishes to
coherently combine the received signal, using the channel estimate. It will then unintentionally
and coherently combine part of the interfering signal as well. This is particularly poisonous
when the base station has M antennas, since the array gain from the receive combining increases
both the signal power and the interference power proportionally to M. Similarly, when the base
station transmits a beamformed downlink signal towards its terminal, it will unintentionally
direct some of the signal towards to interferer.
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31. Massive MIMO in 5G
Figure 5.3: Pilot Contamination
Pilot contamination reduction:
For reducing degradation,this scheduling assigns a optimal pilot sequence to the user who
suffers from the greatest degradation in a greedy way.Moreover,the scheme is further optimized
with an extra set of orthogonal pilot sequences, which is called pilot scheduling scheme based
on user grouping. Simulation results show that the target cell’s achievable sum rate of the
proposed scheme is much higher than the random pilot scheduling (RPS) and the smart pi-
lot assignment (SPA) schemes. Currently, pilot contamination reduction schemes in massive
MIMO systems can be classified into three groups: channel estimation, precoding, and pilot
scheduling.Pilot contamination was tackled by a multi-cell precoding method based on the
minimum mean square error channel estimation. Under the assumption of spatially correlated
channels, it has been found that the pilot contamination would disappear by exploiting the co-
variance information of user channels and using a coordinated pilot assignment strategy among
cells. Alternatively, the concept of time-shifted pilots was proposed to avoid the inter-cell in-
terference via rearranging the order of uplink pilot transmission in different cells. However, this
asynchronous transmission scheme may result in strong interference when two closely located
users in neighboring cells are transmitting or receiving simultaneously. The sparse Bayesian
learning was employed to estimate not only the CSI but also the interference from neighboring
cells.
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32. Massive MIMO in 5G
Chapter 6
SCOPE AND APPLICATION
The cellular world is really starting to dig into massive MIMO because 5G needs it. There
is a limited amount of spectrum available for 5G, so spectral efficiency is very important. 5G
networks will also need to connect to billions of devices. For that to happen they’ll need
massive MIMO’s pinpoint accuracy and energy efficiency.The US government recently opened
up a new part of the high frequency spectrum for 5G technology. That will be very helpful
in the future, but for the short term transition period, frequencies below 6 GHz will provide
a smoother transition from 4G/LTE. It just so happens that massive MIMO operates best
at frequencies below 6 GHz. This band is already crowded, so the extra spectral efficiency
makes massive MIMO a prime candidate.As technology advances our world is becoming more
connected. The Internet of Things is taking off, self driving cars are on the horizon, and there
are already networks in place for smart cities. 5G is poised to move into all of these arenas,
and will need to connect billions of devices. In order to do that it will need massive MIMO to
be able to beam data to and from individual devices. Massive MIMO’s energy efficiency will
also mean that these networks won’t require another oil boom to power them.
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33. Massive MIMO in 5G
Chapter 7
CONCLUSION
The new coming 5G technology is available in the market in affordable rates, high peak
future and much reliability than its preceding technologies.This technology helps to promotes
stronger links between people working in different fields creating future concepts of mobile
communication , internet services , cloud computing , all pie network , and nanotechnology
.Almost Using huge numbers of antennas will allow cell networks to connect large numbers of
users efficiently and reliably. Those attributes also happen to be what’s needed in order to
implement 5G. With billions of devices coming online and a limited frequency spectrum, 5G will
need massive MIMO to help us transition into the future.With these 5G technologies, engineers
hope to build the wireless network that future smartphone users, VR gamers, and autonomous
cars will rely on every day. Already, researchers and companies have set high expectations for
5G by promising ultra-low latency and record-breaking data speeds for consumers. If they can
solve the remaining challenges, and figure out how to make all these systems work together,
ultrafast 5G service could reach consumers in all over the world.
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