Introduction to 5G transmission
technique NOMA
3
Outline
• Introduction
• Literature Review
• Research Problem
• Proposed Method
• Research Objectives
• Applications
• References
4
Introduction
• The use of mobile devices has been increasing in an
exponential fashion from past few years
• The exponential increase in the use of interconnected
mobile devices will result in the growth of data traffic.
• This will force the network operators to increase the
capacity of the networks in a dramatic fashion to meet the
upcoming demands.
Because there are too many users demanding too much data.
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Evolution from 1G to 5G
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HetNets and NOMA
• Heterogeneous Networks and Non orthogonal multiple access
are two significant and promising enabling techniques to further
improve overall system performance for next generation mobile
communication systems [1].
Heterogeneous
Networks
(HetNets)
Non Orthogonal
Multiple Access
(NOMA)
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Heterogeneous Networks (HetNets)
• HetNets are typically composed of a variety of formats of base
station, radio access networks, transmission solutions and
power levels.
• In this way HetNets have several aspects:
Use of multiple radio access technologies
Operation of different cell sizes and approaches
Backhaul
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HetNets
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HetNets versus Power
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HetNets
• HetNets require the changes in following important aspect:
Cell Association
Downlink-Uplink Relationship
Mobility
Interference Management
Many of these issues are still under the research work for
betterment.
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HetNets
• HetNets will play a key role in future of mobile broadband
cellular networks.
• Support shift from spectral efficiency to network efficiency
▫ High capacity at low cost
▫ Flexible deployment and self management
▫ Low power Levels
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HetNets
• Future networks should support explosive mobile data traffic
growth driven by
Multimedia applications
More connected users and devices etc.
• Future networks should be low power, and environment
friendly.
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Non orthogonal multiple access (NOMA)
• Non-orthogonal multiple access is a multiple access technique in
which the user multiplexing is done in the power domain [2].
• The strong users having better channel conditions transmit with
low power and the weak users having worse channels transmit
with high power, while sharing the same spectral resources.
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NOMA
• There are two main techniques employed in NOMA for multiple
access.
• Power domain: Here NOMA achieves multiplexing based on
different power levels.
• Code domain: Here NOMA achieves multiplexing based on
different codes.
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Superimposed Signal (SC)
•
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Successive Interference Cancellation (SIC)
•
Power
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Frequency
SIC of U2
signal
U1 signal
decoding
U1
U2 signal
decoding
U2
BS
High
SINR
Low
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Comparison between OMA and NOMA[3]
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Advantages of NOMA
• Higher spectral efficiency
• Massive connectivity
• Better QoS (Quality of Service) to all the users
• The NOMA along with MIMO delivers enhanced performance.
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Literature Review
• User Clustering, Power Allocation and differences between
Uplink and Downlink .
• There is no proper investigation to precisely analyze the
difference in uplink and downlink NOMA systems and their
respective impact on the user grouping and power allocation
problems [4].
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Literature Review
Downlink NOMA Clustering[4]
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Literature Review
Uplink NOMA Clustering [4]
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Literature Review
• User pairing in a two-user downlink and uplink NOMA cluster
[5].
• Key distinction between uplink and downlink NOMA
Implementation Complexity
Intra-cell/Intra-cluster Interference
SIC at Receiver(s)
Inter-cell Interference
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Literature Review
Downlink User Selection in NOMA [5]
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Literature Review
Uplink User Selection In NOMA [5]
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Literature Review
• NOMA with SIC technology to HetNets in order to alleviate the
cross-tier interference and improve the system energy efficiency
via resource optimization [6].
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Literature Review
• Non-orthogonal multiple access (NOMA) and Heterogeneous
network (HetNets) are two significant and promising enabling
techniques to further improve overall system performance for
next- generation mobile communications systems.
• A novel NOMA HetNets through applying NOMA technique to
both macro cell and small-cell of conventional HetNets, which
improves the spectral efficiency whereas results in a more
complex interference environment [1].
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Research Problem
• Analysis for the uplink NOMA HetNets and their respective
impact on the user grouping and power allocation problems.
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Proposed Method
• Consider Two base station:
i) Macro Base Station (MBS)
ii) Small Base Station (SBS).
• User clustering
• To Apply NOMA based technique to both Macro-cell and
Small-cell of conventional HetNets.
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Proposed Method
• Uplink NOMA in HetNets
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Research Objectives
• To tackle the complicated interference problem and maximize
the throughput of NOMA HetNets.
• To develop a low complexity algorithm for user pairing and
power allocation for Uplink NOMA HetNets.
• Comparison of the developed algorithm with the existing
algorithm.
• To evaluate the system performance.
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Applications
Device to Device
Communications
Internet of
Things (IoT)
Green
Communications
Massive MIMO
Millimeter Wave
& Terahertz band
Big Data &
Mobile
Computing
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References
• [1]” Power Allocation for Downlink NOMA Heterogeneous Networks”
DADONG NI 1, (Student Member, IEEE), LI HAO1, (Member, IEEE), QUANG
THANH TRAN 1,2, AND XIAOMIN QIAN 1 Received April 1, 2018, accepted
May 1, 2018, date of publication May 11, 2018, date of current version June
5, 2018.
• [2] A. Benjebbour, Y. Saito, Y. Kishiyama, A. Li, A. Harada, and T. Nakamura, “Concept
and practical considerations of non-orthogonal multiple access (noma) for future
radio access,” in Intelligent Signal Processing and Communications Systems (ISPACS),
2013 International Symposium on, pp. 770–774, IEEE, 2013.
• [3] Review Article “A Tutorial on Nonorthogonal Multiple Access for 5G and
Beyond” Mahmoud Aldababsa,1 Mesut Toka,1,2 Selahattin Gökçeli ,3 GüneG
Karabulut Kurt,3 and OLuz Kucur 1 Hindawi Wireless Communications and
Mobile Computing Volume 2018, Article ID 9713450, 24 pages
,https://doi.org/10.1155/2018/9713450
34
References
• [4] “Dynamic User Clustering and Power Allocation for Uplink and Downlink
Non-orthogonal Multiple Access” date of publication August 31, 2016 MD
SHIPON ALI, HINA TABASSUM, AND EKRAM HOSSAIN
• [5] ‘Non-Orthogonal Multiple Access (NOMA) in Cellular Uplink and Downlink:
Challenges and Enabling Techniques’,Hina Tabassum, Md Shipon Ali, Ekram
Hossain, Md. Jahangir Hossain, and Dong In Kim, published in 2017
• [6] “Energy-Efficient Resource Allocation in NOMA Heterogeneous Networks”
Haijun Zhang, Fang Fang, Julian Cheng, Keping Long, Wei Wang, and Victor C.
M. Leung IEEE Wireless Communications • April 2018
Thank you!