Uplink Vs. Downlink NOMA in Cellular Networks: Challenges and Research Directions
- Authors
- Tabassum, H.[Tabassum, H.]; Ali, M.S.[Ali, M.S.]; Hossain, E.[Hossain, E.]; Hossain, M.J.[Hossain, M.J.]; Kim, D.I.[Kim, D.I.]
- Issue Date
- 2017
- Publisher
- Institute of Electrical and Electronics Engineers Inc.
- Citation
- IEEE Vehicular Technology Conference, v.2017-June
- Indexed
- SCOPUS
- Journal Title
- IEEE Vehicular Technology Conference
- Volume
- 2017-June
- URI
- https://scholarworks.bwise.kr/skku/handle/2021.sw.skku/32864
- DOI
- 10.1109/VTCSpring.2017.8108691
- ISSN
- 1550-2252
- Abstract
- Non-orthogonal multiple access (NOMA) is a promising multiple access technique for 5G wireless technology. In this paper, we first discuss the fundamentals of uplink and downlink NOMA transmissions in a cellular system and outline their key distinctions in terms of implementation complexity, detection and decoding at the SIC receiver(s), and the intra-cell and inter-cell interferences. Later, for both downlink and uplink NOMA, for each individual user in a two-user NOMA cluster, we theoretically derive the NOMA dominant condition, which refers to the condition under which the spectral efficiency gains of NOMA are guaranteed compared to conventional orthogonal multiple access (OMA). The conditions, which are distinct for uplink and downlink as well as for each individual user, provide direct insights into selecting appropriate users in two-user NOMA clusters. Numerical results show the significance of the derived conditions for user selection in uplink/downlink NOMA clusters and provide a comparison to the random user selection. Finally, a brief summary of the recent research investigations is provided which is followed by a discussion on the research challenges and future research directions. © 2017 IEEE.
- Files in This Item
- There are no files associated with this item.
- Appears in
Collections - Information and Communication Engineering > School of Electronic and Electrical Engineering > 1. Journal Articles
![qrcode](https://api.qrserver.com/v1/create-qr-code/?size=55x55&data=https://scholarworks.bwise.kr/skku/handle/2021.sw.skku/32864)
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.