The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Zhiguo Ding - One of the best experts on this subject based on the ideXlab platform.
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non Orthogonal Multiple access common myths and critical questions
IEEE Wireless Communications, 2019Co-Authors: Mojtaba Vaezi, Zhiguo Ding, Robert Schober, Vincent H PoorAbstract:Non-Orthogonal Multiple access (NOMA) has received tremendous attention for the design of radio access techniques for fifth generation (5G) wireless networks and beyond. The basic concept behind NOMA is to serve more than one user in the same resource block, for example, a time slot, subcarrier, spreading code, or space. With this, NOMA promotes massive connectivity, lowers latency, improves user fairness and spectral efficiency, and increases reliability compared to Orthogonal Multiple access (OMA) techniques. While NOMA has gained significant attention from the communications community, it has also been subject to several widespread misunderstandings, such as "NOMA is based on allocating higher power to users with worse channel conditions. As such, cell-edge users receive more power in NOMA and due to this biased power allocation toward celledge users inter-cell interference is more severe in NOMA compared to OMA. NOMA also compromises security for spectral efficiency." The above statements are actually false, and this article aims at identifying such common myths about NOMA and clarifying why they are not true. We also pose critical questions that are important for the effective adoption of NOMA in 5G and beyond and identify promising research directions for NOMA, which will require intense investigation in the future.
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locally cooperative interference mitigation for small cell networks with non Orthogonal Multiple access a potential game approach
International Conference on Communications, 2018Co-Authors: Xianling Wang, Zhiguo Ding, Haijun Zhang, Yue Tian, Victor C M LeungAbstract:In this paper, we investigate distributed subchannel allocation problem in small cell network (SCN) with non-Orthogonal Multiple access (NOMA) enhancement. Different from existing studies, we exploit NOMA for the purpose of mitigating aggregate inter-cell and intra-cell interference. The problem is analyzed through a locally cooperative game model, in which information is exchanged only among neighboring small cell base stations (SBSs) instead of all SBSs in the SCN. The existence of Nash equilibrium (NE) is confirmed by proving the formulated game as an exact potential game, which allows the application of best response algorithm to solve the problem locally or globally. It is shown that the aggregate interference can be more efficiently suppressed in the NOMA system, compared with traditional Orthogonal Multiple access (OMA) system. Furthermore, as the network grows denser, higher percentage of SBSs have the incentive to Multiplex users via the NOMA technique, revealing the superiority of NOMA over OMA in future ultra dense network.
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a survey of non Orthogonal Multiple access for 5g
IEEE Communications Surveys and Tutorials, 2018Co-Authors: Bichai Wang, Zhaocheng Wang, Zhiguo Ding, Sheng Chen, Lajos HanzoAbstract:In the fifth generation (5G) of wireless communication systems, hitherto unprecedented requirements are expected to be satisfied. As one of the promising techniques of addressing these challenges, non-Orthogonal Multiple access (NOMA) has been actively investigated in recent years. In contrast to the family of conventional Orthogonal Multiple access (OMA) schemes, the key distinguishing feature of NOMA is to support a higher number of users than the number of Orthogonal resource slots with the aid of non-Orthogonal resource allocation. This may be realized by the sophisticated inter-user interference cancellation at the cost of an increased receiver complexity. In this paper, we provide a comprehensive survey of the original birth, the most recent development, and the future research directions of NOMA. Specifically, the basic principle of NOMA will be introduced at first, with the comparison between NOMA and OMA especially from the perspective of information theory. Then, the prominent NOMA schemes are discussed by dividing them into two categories, namely, power-domain and code-domain NOMA. Their design principles and key features will be discussed in detail, and a systematic comparison of these NOMA schemes will be summarized in terms of their spectral efficiency, system performance, receiver complexity, etc. Finally, we will highlight a range of challenging open problems that should be solved for NOMA, along with corresponding opportunities and future research trends to address these challenges.
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short packet downlink transmission with non Orthogonal Multiple access
IEEE Transactions on Wireless Communications, 2018Co-Authors: Xiaofang Sun, Zhiguo Ding, Chao Shen, Nan Yang, Zhangdui ZhongAbstract:This paper introduces downlink non-Orthogonal Multiple access (NOMA) into short-packet communications. NOMA has great potential to improve fairness and spectral efficiency with respect to Orthogonal Multiple access (OMA) for low-latency downlink transmission, thus making it attractive for the emerging Internet of Things. We consider a two-user downlink NOMA system with finite blocklength constraints, in which the transmission rates and power allocation are optimized. To this end, we investigate the trade-off among the transmission rate, decoding error probability, and the transmission latency measured in blocklength. Then, a 1-D search algorithm is proposed to resolve the challenges mainly due to the achievable rate affected by the finite blocklength and the unguaranteed successive interference cancellation. We also analyze the performance of OMA as a benchmark to fully demonstrate the benefit of NOMA. Our simulation results show that NOMA significantly outperforms OMA in terms of achieving a higher effective throughput subject to the same finite blocklength constraint, or incurring a lower latency to achieve the same effective throughput target. Interestingly, we further find that with the finite blocklength, the advantage of NOMA relative to OMA is more prominent when the effective throughput targets at the two users become more comparable.
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Toward the Standardization of Non-Orthogonal Multiple Access for Next Generation Wireless Networks
IEEE Communications Magazine, 2018Co-Authors: Yan Chen, Bin Ren, Shaohui Sun, Shaoli Kang, Alireza Bayesteh, Yiqun Wu, Qi Xiong, Chen Qian, Bin Yu, Zhiguo DingAbstract:Non-Orthogonal Multiple access (NOMA) as an efficient method of radio resource sharing has its roots in network information theory. For generations of wireless communication systems design, Orthogonal Multiple access schemes in the time, frequency, or code domain have been the main choices due to the limited processing capability in the transceiver hardware, as well as the modest traffic demands in both latency and connectivity. However, for the next generation radio systems, given its vision to connect everything and the much evolved hardware capability, NOMA has been identified as a promising technology to help achieve all the targets in system capacity, user connectivity, and service latency. This article provides a systematic overview of the state-of-the-art design of the NOMA transmission based on a unified transceiver design framework, the related standardization progress, and some promising use cases in future cellular networks, based on which interested researchers can get a quick start in this area.
Vincent H Poor - One of the best experts on this subject based on the ideXlab platform.
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ris enhanced massive non Orthogonal Multiple access networks deployment and passive beamforming design
IEEE Journal on Selected Areas in Communications, 2020Co-Authors: Xiao Liu, Yuanwei Liu, Yue Chen, Vincent H PoorAbstract:A novel framework is proposed for the deployment and passive beamforming design of a reconfigurable intelligent surface (RIS) with the aid of non-Orthogonal Multiple access (NOMA) technology. The problem of joint deployment, phase shift design, as well as power allocation in the Multiple-inputsingle-output (MISO) NOMA network is formulated for maximizing the energy efficiency with considering users particular data requirements. To tackle this pertinent problem, machine learning approaches are adopted in two steps. Firstly, a novel long short-term memory (LSTM) based echo state network (ESN) algorithm is proposed to predict users’ tele-traffic demand by leveraging a real dataset. Secondly, a decaying double deep Qnetwork (D3QN) based position-acquisition and phase-control algorithm is proposed to solve the joint problem of deployment and design of the RIS. In the proposed algorithm, the base station, which controls the RIS by a controller, acts as an agent. The agent periodically observes the state of the RIS-enhanced system for attaining the optimal deployment and design policies of the RIS by learning from its mistakes and the feedback of users. Additionally, it is proved that the proposed D3QN based deployment and design algorithm is capable of converging within mild conditions. Simulation results are provided for illustrating that the proposed LSTM-based ESN algorithm is capable of striking a tradeoff between the prediction accuracy and computational complexity. Finally, it is demonstrated that the proposed D3QN based algorithm outperforms the benchmarks, while the NOMA-enhanced RIS system is capable of achieving higher energy efficiency than Orthogonal Multiple access (OMA) enabled RIS system.
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ris enhanced massive non Orthogonal Multiple access networks deployment and passive beamforming design
arXiv: Signal Processing, 2020Co-Authors: Xiao Liu, Yuanwei Liu, Yue Chen, Vincent H PoorAbstract:A novel framework is proposed for the deployment and passive beamforming design of a reconfigurable intelligent surface (RIS) with the aid of non-Orthogonal Multiple access (NOMA) technology. The problem of joint deployment, phase shift design, as well as power allocation is formulated for maximizing the energy efficiency with considering users' particular data requirements. To tackle this pertinent problem, machine learning approaches are adopted in two steps. Firstly, a novel long short-term memory (LSTM) based echo state network (ESN) algorithm is proposed to predict users' tele-traffic demand by leveraging a real dataset. Secondly, a decaying double deep Q-network (D3QN) based position-acquisition and phase-control algorithm is proposed to solve the joint problem of deployment and design of the RIS. In the proposed algorithm, the base station, which controls the RIS by a controller, acts as an agent. The agent periodically observes the state of the RIS-enhanced system for attaining the optimal deployment and design policies of the RIS by learning from its mistakes and the feedback of users. Additionally, it is proved that the proposed D3QN based deployment and design algorithm is capable of converging within mild conditions. Simulation results are provided for illustrating that the proposed LSTM-based ESN algorithm is capable of striking a tradeoff between the prediction accuracy and computational complexity. Finally, it is demonstrated that the proposed D3QN based algorithm outperforms the benchmarks, while the NOMA-enhanced RIS system is capable of achieving higher energy efficiency than Orthogonal Multiple access (OMA) enabled RIS system.
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non Orthogonal Multiple access common myths and critical questions
IEEE Wireless Communications, 2019Co-Authors: Mojtaba Vaezi, Zhiguo Ding, Robert Schober, Vincent H PoorAbstract:Non-Orthogonal Multiple access (NOMA) has received tremendous attention for the design of radio access techniques for fifth generation (5G) wireless networks and beyond. The basic concept behind NOMA is to serve more than one user in the same resource block, for example, a time slot, subcarrier, spreading code, or space. With this, NOMA promotes massive connectivity, lowers latency, improves user fairness and spectral efficiency, and increases reliability compared to Orthogonal Multiple access (OMA) techniques. While NOMA has gained significant attention from the communications community, it has also been subject to several widespread misunderstandings, such as "NOMA is based on allocating higher power to users with worse channel conditions. As such, cell-edge users receive more power in NOMA and due to this biased power allocation toward celledge users inter-cell interference is more severe in NOMA compared to OMA. NOMA also compromises security for spectral efficiency." The above statements are actually false, and this article aims at identifying such common myths about NOMA and clarifying why they are not true. We also pose critical questions that are important for the effective adoption of NOMA in 5G and beyond and identify promising research directions for NOMA, which will require intense investigation in the future.
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non Orthogonal Multiple access in multi cell networks theory performance and practical challenges
IEEE Communications Magazine, 2017Co-Authors: Wonjae Shin, Mojtaba Vaezi, David J Love, Vincent H PoorAbstract:Non-Orthogonal Multiple access (NOMA) is a potential enabler for the development of 5G and beyond wireless networks. By allowing Multiple users to share the same time and frequency, NOMA can scale up the number of served users, increase spectral efficiency, and improve user-fairness compared to existing Orthogonal Multiple access (OMA) techniques. While single-cell NOMA has drawn significant attention recently, much less attention has been given to multi-cell NOMA. This article discusses the opportunities and challenges of NOMA in a multi-cell environment. As the density of base stations and devices increases, inter-cell interference becomes a major obstacle in multi-cell networks. As such, identifying techniques that combine interference management approaches with NOMA is of great significance. After discussing the theory behind NOMA, this article provides an overview of the current literature and discusses key implementation and research challenges, with an emphasis on multi-cell NOMA.
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application of non Orthogonal Multiple access in lte and 5g networks
IEEE Communications Magazine, 2017Co-Authors: Zhiguo Ding, Yuanwei Liu, Maged Elkashlan, Jinho Choi, Qi Sun, I Chihlin, Vincent H PoorAbstract:As the latest member of the Multiple access family, non-Orthogonal Multiple access (NOMA) has been recently proposed for 3GPP LTE and is envisioned to be an essential component of 5G mobile networks. The key feature of NOMA is to serve Multiple users at the same time/frequency/ code, but with different power levels, which yields a significant spectral efficiency gain over conventional Orthogonal MA. The article provides a systematic treatment of this newly emerging technology, from its combination with MIMO technologies to cooperative NOMA, as well as the interplay between NOMA and cognitive radio. This article also reviews the state of the art in the standardization activities concerning the implementation of NOMA in LTE and 5G networks.
George K. Karagiannidis - One of the best experts on this subject based on the ideXlab platform.
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wireless powered communications with non Orthogonal Multiple access
IEEE Transactions on Wireless Communications, 2016Co-Authors: Panagiotis D Diamantoulakis, Zhiguo Ding, Koralia N Pappi, George K. KaragiannidisAbstract:We study a wireless-powered uplink communication system with non-Orthogonal Multiple access (NOMA), consisting of one base station and Multiple energy harvesting users. More specifically, we focus on the individual data rate optimization and fairness improvement and we show that the formulated problems can be optimally and efficiently solved by either linear programming or convex optimization. In the provided analysis, two types of decoding order strategies are considered, namely fixed decoding order and time sharing . Furthermore, we propose an efficient greedy algorithm, which is suitable for the practical implementation of the time-sharing strategy. The simulation results illustrate that the proposed scheme outperforms the baseline Orthogonal Multiple access scheme. More specifically, it is shown that the NOMA offers a considerable improvement in throughput, fairness, and energy efficiency. Also, the dependence among system throughput, minimum individual data rate, and harvested energy is revealed, as well as an interesting tradeoff between rates and energy efficiency. Finally, the convergence speed of the proposed greedy algorithm is evaluated, and it is shown that the required number of iterations is linear with respect to the number of users.
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Non-Orthogonal Multiple Access for Visible Light Communications
IEEE Photonics Technology Letters, 2016Co-Authors: Hanaa Marshoud, Vasileios M. Kapinas, George K. Karagiannidis, Sami MuhaidatAbstract:The main limitation of visible light communication (VLC) is the narrow modulation bandwidth, which reduces the achievable data rates. In this letter, we apply the non-Orthogonal Multiple access (NOMA) scheme to enhance the achievable throughput in high-rate VLC downlink networks. We first propose a novel gain ratio power allocation (GRPA) strategy that considers the users’ channel conditions to ensure efficient and fair power allocation. Our results indicate that the GRPA significantly enhances the system performance compared with the static power allocation. We also study the effect of tuning the transmission angles of the light emitting diodes and the field of views of the receivers, and demonstrate that these parameters can offer new degrees of freedom to boost the NOMA performance. The simulation results reveal that NOMA is a promising Multiple access scheme for the downlink of VLC networks.
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A Minorization-Maximization Method for Optimizing Sum Rate in the Downlink of Non-Orthogonal Multiple Access Systems
IEEE Transactions on Signal Processing, 2016Co-Authors: Muhammad Fainan Hanif, Zhiguo Ding, Tharmalingam Ratnarajah, George K. KaragiannidisAbstract:Non-Orthogonal Multiple access (NOMA) systems have the potential to deliver higher system throughput, compared with contemporary Orthogonal Multiple access techniques. For a linearly precoded Multiple-input single-output (MISO) system, we study the downlink sum rate maximization problem, when the NOMA principle is applied. Being a non-convex and intractable optimization problem, we resort to approximate it with a minorization-maximization algorithm (MMA), which is a widely used tool in statistics. In each step of the MMA, we solve a second-order cone program, such that the feasibility set in each step contains that of the previous one, and is always guaranteed to be a subset of the feasibility set of the original problem. It should be noted that the algorithm takes a few iterations to converge. Furthermore, we study the conditions under which the achievable rates maximization can be further simplified to a low complexity design problem, and we compute the probability of occurrence of this event. Numerical examples are conducted to show a comparison of the proposed approach against conventional Multiple access systems.
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wireless powered communications with non Orthogonal Multiple access
arXiv: Information Theory, 2015Co-Authors: Panagiotis D Diamantoulakis, Zhiguo Ding, Koralia N Pappi, George K. KaragiannidisAbstract:We study a wireless-powered uplink communication system with non-Orthogonal Multiple access (NOMA), consisting of one base station and Multiple energy harvesting users. More specifically, we focus on the individual data rate optimization and fairness improvement and we show that the formulated problems can be optimally and efficiently solved by either linear programming or convex optimization. In the provided analysis, two types of decoding order strategies are considered, namely fixed decoding order and time- sharing. Furthermore, we propose an efficient greedy algorithm, which is suitable for the practical implementation of the time-sharing strategy. Simulation results illustrate that the proposed scheme outperforms the baseline Orthogonal Multiple access scheme. More specifically, it is shown that NOMA offers a considerable improvement in throughput, fairness, and energy efficiency. Also, the dependence among system throughput, minimum individual data rate, and harvested energy is revealed, as well as an interesting trade-off between rates and energy efficiency. Finally, the convergence speed of the proposed greedy algorithm is evaluated, and it is shown that the required number of iterations is linear with respect to the number of users.
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non Orthogonal Multiple access for visible light communications
arXiv: Information Theory, 2015Co-Authors: Hanaa Marshoud, Vasileios M. Kapinas, George K. Karagiannidis, Sami MuhaidatAbstract:The main limitation of visible light communication (VLC) is the narrow modulation bandwidth, which reduces the achievable data rates. In this paper, we apply the non-Orthogonal Multiple access (NOMA) scheme to enhance the achievable throughput in high-rate VLC downlink networks. We first propose a novel gain ratio power allocation (GRPA) strategy that takes into account the users' channel conditions to ensure efficient and fair power allocation. Our results indicate that GRPA significantly enhances system performance compared to the static power allocation. We also study the effect of tuning the transmission angles of the light emitting diodes (LEDs) and the field of views (FOVs) of the receivers, and demonstrate that these parameters can offer new degrees of freedom to boost NOMA performance. Simulation results reveal that NOMA is a promising Multiple access scheme for the downlink of VLC networks.
Yuanwei Liu - One of the best experts on this subject based on the ideXlab platform.
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ris enhanced massive non Orthogonal Multiple access networks deployment and passive beamforming design
IEEE Journal on Selected Areas in Communications, 2020Co-Authors: Xiao Liu, Yuanwei Liu, Yue Chen, Vincent H PoorAbstract:A novel framework is proposed for the deployment and passive beamforming design of a reconfigurable intelligent surface (RIS) with the aid of non-Orthogonal Multiple access (NOMA) technology. The problem of joint deployment, phase shift design, as well as power allocation in the Multiple-inputsingle-output (MISO) NOMA network is formulated for maximizing the energy efficiency with considering users particular data requirements. To tackle this pertinent problem, machine learning approaches are adopted in two steps. Firstly, a novel long short-term memory (LSTM) based echo state network (ESN) algorithm is proposed to predict users’ tele-traffic demand by leveraging a real dataset. Secondly, a decaying double deep Qnetwork (D3QN) based position-acquisition and phase-control algorithm is proposed to solve the joint problem of deployment and design of the RIS. In the proposed algorithm, the base station, which controls the RIS by a controller, acts as an agent. The agent periodically observes the state of the RIS-enhanced system for attaining the optimal deployment and design policies of the RIS by learning from its mistakes and the feedback of users. Additionally, it is proved that the proposed D3QN based deployment and design algorithm is capable of converging within mild conditions. Simulation results are provided for illustrating that the proposed LSTM-based ESN algorithm is capable of striking a tradeoff between the prediction accuracy and computational complexity. Finally, it is demonstrated that the proposed D3QN based algorithm outperforms the benchmarks, while the NOMA-enhanced RIS system is capable of achieving higher energy efficiency than Orthogonal Multiple access (OMA) enabled RIS system.
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ris enhanced massive non Orthogonal Multiple access networks deployment and passive beamforming design
arXiv: Signal Processing, 2020Co-Authors: Xiao Liu, Yuanwei Liu, Yue Chen, Vincent H PoorAbstract:A novel framework is proposed for the deployment and passive beamforming design of a reconfigurable intelligent surface (RIS) with the aid of non-Orthogonal Multiple access (NOMA) technology. The problem of joint deployment, phase shift design, as well as power allocation is formulated for maximizing the energy efficiency with considering users' particular data requirements. To tackle this pertinent problem, machine learning approaches are adopted in two steps. Firstly, a novel long short-term memory (LSTM) based echo state network (ESN) algorithm is proposed to predict users' tele-traffic demand by leveraging a real dataset. Secondly, a decaying double deep Q-network (D3QN) based position-acquisition and phase-control algorithm is proposed to solve the joint problem of deployment and design of the RIS. In the proposed algorithm, the base station, which controls the RIS by a controller, acts as an agent. The agent periodically observes the state of the RIS-enhanced system for attaining the optimal deployment and design policies of the RIS by learning from its mistakes and the feedback of users. Additionally, it is proved that the proposed D3QN based deployment and design algorithm is capable of converging within mild conditions. Simulation results are provided for illustrating that the proposed LSTM-based ESN algorithm is capable of striking a tradeoff between the prediction accuracy and computational complexity. Finally, it is demonstrated that the proposed D3QN based algorithm outperforms the benchmarks, while the NOMA-enhanced RIS system is capable of achieving higher energy efficiency than Orthogonal Multiple access (OMA) enabled RIS system.
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toward cross layer design for non Orthogonal Multiple access a quality of experience perspective
IEEE Wireless Communications, 2018Co-Authors: Wei Wang, Yuanwei Liu, Zhiqing Luo, Tao Jiang, Qian Zhang, Arumugam NallanathanAbstract:Recent years have seen a proliferation in versatile mobile devices and an upsurge in the growth of data-consuming application services. Orthogonal Multiple access technologies in today's mobile systems are inefficient in the presence of such massive connectivity and traffic demands. In this regard, non-Orthogonal Multiple access has been advocated by the research community to embrace unprecedented requirements. Current NOMA designs have been demonstrated to largely improve conventional system performance in terms of throughput and latency, while their impact on end users' perceived experience has not yet been comprehensively understood. We envision that quality of experience awareness is a key pillar for NOMA designs to fulfill versatile user demands in 5G wireless communication systems. This article systematically investigates QoE-aware NOMA designs that translate the physical-layer benefits of NOMA to the improvement of users' perceived experience in upper layers. We shed light on design principles and key challenges in realizing QoE-aware NOMA designs. With these principles and challenges in mind, we develop a general architecture with a dynamic network scheduling scheme. We provide some implications for future QoE-aware NOMA designs by conducting a case study in video streaming applications.
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toward cross layer design for non Orthogonal Multiple access a quality of experience perspective
arXiv: Networking and Internet Architecture, 2018Co-Authors: Wei Wang, Yuanwei Liu, Zhiqing Luo, Tao Jiang, Qian Zhang, Arumugam NallanathanAbstract:Recent years have seen proliferation in versatile mobile devices and an upsurge in the growth of data-consuming application services. Orthogonal Multiple access (OMA) technologies in today's mobile systems fall inefficient in the presence of such massive connectivity and traffic demands. In this regards, non-Orthogonal Multiple access (NOMA) has been advocated by the research community to embrace unprecedented requirements. Current NOMA designs have been demonstrated to largely improve conventional system performance in terms of throughput and latency, while their impact on the end users' perceived experience has not yet been comprehensively understood. We envision that quality-of-experience (QoE) awareness is a key pillar for NOMA designs to fulfill versatile user demands in the 5th generation (5G) wireless communication systems. This article systematically investigates QoE-aware NOMA designs that translate the physical-layer benefits of NOMA to the improvement of users' perceived experience in upper layers. We shed light on design principles and key challenges in realizing QoE-aware NOMA designs. With these principles and challenges in mind, we develop a general architecture with a dynamic network scheduling scheme. We provide some implications for future QoE-aware NOMA designs by conducting a case study in video streaming applications.
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application of non Orthogonal Multiple access in lte and 5g networks
IEEE Communications Magazine, 2017Co-Authors: Zhiguo Ding, Yuanwei Liu, Maged Elkashlan, Jinho Choi, Qi Sun, I Chihlin, Vincent H PoorAbstract:As the latest member of the Multiple access family, non-Orthogonal Multiple access (NOMA) has been recently proposed for 3GPP LTE and is envisioned to be an essential component of 5G mobile networks. The key feature of NOMA is to serve Multiple users at the same time/frequency/ code, but with different power levels, which yields a significant spectral efficiency gain over conventional Orthogonal MA. The article provides a systematic treatment of this newly emerging technology, from its combination with MIMO technologies to cooperative NOMA, as well as the interplay between NOMA and cognitive radio. This article also reviews the state of the art in the standardization activities concerning the implementation of NOMA in LTE and 5G networks.
Takehiro Nakamura - One of the best experts on this subject based on the ideXlab platform.
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system level performance of downlink non Orthogonal Multiple access noma under various environments
Vehicular Technology Conference, 2015Co-Authors: Yuya Saito, Anass Benjebbour, Yoshihisa Kishiyama, Takehiro NakamuraAbstract:Non-Orthogonal Multiple access (NOMA) is a promising Multiple access scheme for further improving the spectrum efficiency compared to that for Orthogonal Multiple access (OMA) in the 5th Generation (5G) mobile communication systems. All of the existing evaluations for NOMA focus on the macrocell deployment since NOMA fully utilizes the power domain and the difference in channel gains, e.g., path loss, between users, which is typically sufficiently large in macrocells. Currently, small cells are becoming important and being studied for future Long-Term Evolution (LTE) enhancements in order to improve further the system performance. Thus, it is of great interest to study the performance of NOMA for small cell deployment under various environments. This paper investigates the system level performance of NOMA in small cells considering practical assumptions such as the single user Multiple-input Multiple-output (SU-MIMO) technique, adaptive modulation and coding (AMC), feedback channel quality indicator (CQI). Some of the key NOMA specific functionalities, including multi-user paring and transmit power allocation are also taken into account in the evaluation. Based on computer simulations, we show that for both macrocell and small cell deployments, NOMA can still provide a larger throughput performance gain compared to that for OMA.
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system level performance evaluation of downlink non Orthogonal Multiple access noma
Personal Indoor and Mobile Radio Communications, 2013Co-Authors: Yuya Saito, Anass Benjebbour, Yoshihisa Kishiyama, Takehiro NakamuraAbstract:As a promising downlink Multiple access scheme for further LTE enhancement and future radio access (FRA), this paper investigates the system-level performance of non-Orthogonal Multiple access (NOMA) with a successive interference canceller (SIC) on the receiver side. The goal is to clarify the potential gains of NOMA over Orthogonal Multiple access (OMA) such as OFDMA, taking into account key link adaptation functionalities of the LTE radio interface such as adaptive modulation and coding (AMC), hybrid automatic repeat request (HARQ), time/frequency-domain scheduling, and outer loop link adaptation (OLLA), in addition to NOMA specific functionalities such as dynamic multi-user power allocation. Based on computer simulations, we show under Multiple configurations that the system-level performance achieved by NOMA is superior to that for OMA.
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concept and practical considerations of non Orthogonal Multiple access noma for future radio access
International Symposium on Intelligent Signal Processing and Communication Systems, 2013Co-Authors: Anass Benjebbour, Atsushi Harada, Yuya Saito, Yoshihisa Kishiyama, Takehiro NakamuraAbstract:As a promising downlink Multiple access scheme for future radio access (FRA), this paper discusses the concept and practical considerations of non-Orthogonal Multiple access (NOMA) with a successive interference canceller (SIC) at the receiver side. The goal is to clarify the benefits of NOMA over Orthogonal Multiple access (OMA) such as OFDMA adopted by Long-Term Evolution (LTE). Practical considerations of NOMA, such as multi-user power allocation, signalling overhead, SIC error propagation, performance in high mobility scenarios, and combination with Multiple input Multiple output (MIMO) are discussed. Using computer simulations, we provide system-level performance of NOMA taking into account practical aspects of the cellular system and some of the key parameters and functionalities of the LTE radio interface such as adaptive modulation and coding (AMC) and frequency-domain scheduling. We show under Multiple configurations that the system-level performance achieved by NOMA is higher by more than 30% compared to OMA.