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. 5 Evolution from 1G to 5G 6 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) 7 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 8 HetNets 9 HetNets versus Power 10 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. 11 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 12 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. 13 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. 14 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. 15 Superimposed Signal (SC) • 16 Successive Interference Cancellation (SIC) • Power 17 Frequency SIC of U2 signal U1 signal decoding U1 U2 signal decoding U2 BS High SINR Low 18 Comparison between OMA and NOMA[3] 19 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. 20 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]. 21 Literature Review Downlink NOMA Clustering[4] 22 Literature Review Uplink NOMA Clustering [4] 23 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 24 Literature Review Downlink User Selection in NOMA [5] 25 Literature Review Uplink User Selection In NOMA [5] 26 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]. 27 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]. 28 Research Problem • Analysis for the uplink NOMA HetNets and their respective impact on the user grouping and power allocation problems. 29 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. 30 Proposed Method • Uplink NOMA in HetNets 31 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. 32 Applications Device to Device Communications Internet of Things (IoT) Green Communications Massive MIMO Millimeter Wave & Terahertz band Big Data & Mobile Computing 33 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!