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MIMO Transmission with Limited Feedback

Markus Rupp, Ana I. Pérez-Neira, David Gesbert, Christoph F. Mecklenbräuker
2008 EURASIP Journal on Advances in Signal Processing  
The feedback consists of channel direction information (CDI) based on a predetermined codebook and a scalar metric with channel quality information (CQI) to perform user scheduling.  ...  Particularly, the sum rates of SDMA and time-division multiple access (TDMA) are compared in the extreme regimes: large number of users, high SNR, and low SNR.  ...  Particularly, the sum rates of SDMA and time-division multiple access (TDMA) are compared in the extreme regimes: large number of users, high SNR, and low SNR.  ... 
doi:10.1155/2008/518950 fatcat:okyhyovgdjhdbh7ixmsm6mwid4

An Approach For Real Time Prototyping Of Mimo-Ofdm Systems

Sven Janssens, Stefaan Derore, Andre Bourdoux, Maryse Wouters, Veerle Derudder
2004 Zenodo  
Publication in the conference proceedings of EUSIPCO, Viena, Austria, 2004  ...  A 2-antenna MIMO-OFDM system with a doubled downlink capacity compared with IEEE.11a standard is prototyped on the platform. An overview of the hardware resources is given.  ...  OVERVIEW OF MIMO ALGORITHMS WITH TRANSMITTER PROCESSING The system model is described as an OFDM/SDMA system with A antennas at the base station and U single antenna terminals.  ... 
doi:10.5281/zenodo.38558 fatcat:levpztfysjfxldhvx37zfrfpuq

Multiple Access Techniques for Next Generation Wireless: Recent Advances and Future Perspectives

Shree Krishna Sharma, Mohammad Patwary, Symeon Chatzinotas
2016 EAI Endorsed Transactions on Wireless Spectrum  
The proposed concept envisions to employ joint antenna coding in order to enhance the orthogonality of SDMA beams with the objective of enhancing the spectral efficiency of future cellular networks.  ...  In this context, this paper first provides a detailed review on the existing Space Division Multiple Access (SDMA) related works.  ...  enhance the capacity of OFDM-SDMA systems.  ... 
doi:10.4108/eai.19-1-2016.151002 fatcat:7yxosuz675efvpme6b47bm5idu

Rate-Splitting Multiple Access: Unifying NOMA and SDMA in MISO VLC Channels [article]

Shimaa Naser, Lina Bariah, Wael Jaafar, Sami Muhaidat, Paschalis C. Sofotasios, Mahmoud Al-Qutayri, Octavia A. Dobre
2020 arXiv   pre-print
Through system modeling and simulations of an RSMA-based two-use scenario, we illustrate the flexibility of RSMA in generalizing NOMA and SDMA, as well as its superiority in terms of weighted sum rate  ...  Despite their promising multiplexing gains, their performance is somewhat limited. In this article, we first provide an overview of the key MA technologies used in VLC systems.  ...  Most research effort has focused on the analysis of downlink BC of MU-MIMO, with an emphasis on the data rate performance.  ... 
arXiv:2007.13560v1 fatcat:j4bhz64ca5dnlj7ew4du4sv2ii

Multiple Access for Visible Light Communications: Research Challenges and Future Trends [article]

Sarah S. Bawazir, Paschalis C. Sofotasios, Sami Muhaidat, Yousof Al-Hammadi, George K. Karagiannidis
2016 arXiv   pre-print
In this context, we initially provide a thorough overview of frequency domain multiple access techniques for single and multi-carrier systems, which is then followed by an in depth discussion on the technical  ...  To this end, the present article provides a comprehensive overview of a particularly promising and effective wireless technology, namely, visible light communication (VLC).  ...  Based on this, NOMA was thoroughly analyzed in [15] and compared against OFDMA in the context of a VLC downlink scenario with two users.  ... 
arXiv:1612.05894v1 fatcat:swn7cgozg5e53afvqjhhcksem4

Advances in MIMO Techniques for Mobile Communications—A Survey

Farhan Khalid, Joachim Speidel
2010 International Journal of Communications, Network and System Sciences  
A detailed review of various MU-MIMO uplink and downlink techniques then follows, clarifying the underlying concepts and emphasizing the importance of MU-MIMO in cellular communication systems.  ...  This paper also touches upon the topic of MU-MIMO capacity as well as the promising convex optimization approaches to MIMO system design. where Q is an N  M unitary matrix with orthonormal columns, R  ...  It specifies an OFDM based system with support for MIMO. Downlink transmission is based on OFDMA while SC-FDMA is used for the uplink due to its low PAPR characteristics.  ... 
doi:10.4236/ijcns.2010.33031 fatcat:wyhhqdwt5nablim2rvqij2osju

A Survey of NOMA for VLC Systems: Research Challenges and Future Trends

Hesham Sadat, Mohamed Abaza, Ali Mansour, Ayman Alfalou
2022 Sensors  
The power domain nonorthogonal multiple access (PD-NOMA) scheme is envisioned to address several challenges in VLC systems. In this paper, we present a detailed overview of PD-NOMA based VLC systems.  ...  Moreover, we introduce insights on some PD-NOMA VLC system constraints and challenges such as power allocation, clipping effect, MIMO and security.  ...  Block diagram of a two-user downlink DCO-OFDM-based PD-NOMA-VLC system. Figure 11 . 11 Figure 11. Block diagram of 2 × 2 MIMO-PD-NOMA-based VLC system with N users.  ... 
doi:10.3390/s22041395 pmid:35214296 pmcid:PMC8962994 fatcat:qhjvxjkt2jcptm7cfsyot6wk6u

Optical Rate-Splitting Multiple Access for Visible Light Communications [article]

Shimaa Naser, Lina Bariah, Wael Jaafar, Sami Muhaidat, Paschalis C. Sofotasios, Mahmoud Al-Qutayri, Octavia A. Dobre
2020 arXiv   pre-print
We first provide an overview of the key multiple access technologies used in VLC systems. Then, we propose the first comprehensive approach to the integration of RSMA with VLC systems.  ...  In spite of their promising gains, the performance of these techniques is somewhat limited.  ...  Most research focused on the analysis of the downlink BC of MU-MIMO, with an emphasis on the data rate performance.  ... 
arXiv:2002.07583v2 fatcat:hlfxktsvbjag7mi2jyzeqlmbtu

Evolution from TD-SCDMA to FuTURE [chapter]

Xiaodong Xu, Lihua Li, Ping Zhang
2009 Internet and Communications  
Furthermore, DCA can be combined with a smart antenna and GDAA so as to improve the system performance using SDMA.  ...  Therefore, an efficient frequency reuse strategy, as well as enhancing performance for the cell-edge users, is still left as an open research issue for those FDMA-based systems.  ... 
doi:10.1201/9781420072112.ch2 fatcat:xnhslgf2qfhe5gadpbmzzyc45u

Multiuser MIMO-OFDM for Next-Generation Wireless Systems

Ming Jiang, Lajos Hanzo
2007 Proceedings of the IEEE  
for MIMO-OFDM systems and characterizes their achievable performance.  ...  The amelioration of powerful multicarrier OFDM arrangements with multiple-input multiple-output (MIMO) systems has numerous benefits, which are detailed in this treatise.  ...  Enhanced GA MUDs In order to further improve the achievable performance of MIMO SDMA-OFDM systems, the enhanced GA-based MUDs of [281] , [282] can be employed, which improve the detector's performance  ... 
doi:10.1109/jproc.2007.898869 fatcat:mzfhdw6hyzbvrgraoly4mdpapq

Joint Power Allocation and Scheduling of Multi-Antenna OFDM System in Broadcast Channel

F. She, W. Chen, H. Luo, T. Huang, X. Wang
2009 2009 IEEE International Conference on Communications  
We present joint user selection algorithms for DPC, ZF-DPC, ZFBF and TDMA for multi-antenna OFDM system in broadcast channels, and we also present a practical waterfilling solution in this paper.  ...  This paper considers the general multiuser downlink scheduling problem and power minimization with multiuser rate constraints.  ...  In multiuser MIMO-OFDM system, we consider a wireless communication system with one base station and K users. The base station is with N t In an OFDM symbol, the number of total subcarrier is N c .  ... 
doi:10.1109/icc.2009.5199118 dblp:conf/icc/SheCLHW09 fatcat:eqynk4sdczekde5msiwtcyue6q

Impact of the Transmission Scheme on the Performance in Wireless LANs [chapter]

Andreas Könsgen, Andreas Timm-Giel, Carmelita Görg, Ronald Böhnke
2009 Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering  
For MIMO-TDMA and -OFDMA, channel knowledge at the PHY layer does not result in essential performance enhancement.  ...  MISO-SDMA has a relatively small performance penalty in comparison to MIMO-SDMA which gives the best result.  ...  An OFDM transmission system is used with N M = 32 subcarriers working at a carrier frequency f C of 5.2 GHz with a channel bandwidth of 40 MHz.  ... 
doi:10.1007/978-3-642-03819-8_29 fatcat:xpg6lfufyvcezeisq2tz7s6r6e

Multi-User Visible Light Communications: State-of-the-Art and Future Directions

Saad Al-Ahmadi, Omar Maraqa, Murat Uysal, Sadiq M. Sait
2018 IEEE Access  
While initial studies in this area are mainly limited to single-user point-to-point links, more recent efforts have focused on multi-user VLC systems in an effort to transform VLC into a scalable and fully  ...  In this paper, we provide a comprehensive overview of multi-user VLC systems discussing the recent advances on multi-user precoding, multiple access, resource allocation, and mobility management.  ...  [82] proposed an adaptive OFDM VLC system which allows MIMO mode switching based on channel conditions.  ... 
doi:10.1109/access.2018.2879885 fatcat:y7ltnuy4yjfzzggeaolnasttz4

Towards 5th generation cellular mobile networks

Jian A. Zhang, Peng Cheng, Andrew R. Weily, Y. Jay Guo
2014 Australian Journal of Telecommunications and the Digital Economy  
dense small cells, and provide an indepth discussion on potential enabling techniques for the next generation (5G) cellular networks, particularly massive MIMO and multiband base-station antennas.  ...  In this article, we show the path of the evolution in both standards and techniques, and provide our vision for the future of the cellular networks.  ...  Based on the law of large numbers, the deterministic channel makes frequency domain scheduling unnecessary. Each subcarrier in a massive MIMO-OFDM system will approach the same channel gain.  ... 
doi:10.7790/ajtde.v2n2.34 fatcat:43ixpaqptzdybafodcglgnakwq

Rate-Splitting Multiple Access: Unifying NOMA and SDMA in MISO VLC Channels

Shimaa Ayman Naser, Paschalis C. Sofotasios, Lina Bariah, Wael Jaafar, Sami Muhaidat, Mahmoud Al-Qutayri, Octavia A. Dobre
2020 IEEE Open Journal of Vehicular Technology  
However, despite their achievable multiplexing gain, their overall performance is still limited compared to the overall potential of this technology.  ...  Secondly, through realistic system modeling and simulations of an RSMA-based two-user scenario, we illustrate the flexibility of RSMA as well as its superiority in terms of the achievable weighted sum  ...  In particular, research results have shown that RSMA in MIMO-based RF systems outperforms other common MA schemes, such as NOMA and SDMA, in terms of both spectral and energy efficiency [24] .  ... 
doi:10.1109/ojvt.2020.3031656 fatcat:2eu67wbpgrdsdpdcehppv6zr6e
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