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SARA: Sparse Code Multiple Access-Applied Random Access for IoT Devices
IEEE Internet of Things Journal, 2018In this paper, we study a random access (RA) procedure to support the massive connectivity of the Internet of Things (IoT) devices, also known as the IoT connectivity. Compared with the previous RA procedures that have limitations to support the IoT connectivity due to the exponentially increased access delay, we develop an RA procedure by applying the
Seokjae Moon, Hyun-Suk Lee, Jang-Won Lee
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Polar coded iterative multiuser detection for sparse code multiple access system
China Communications, 2018Polar coded sparse code multiple access (SCMA) system is conceived in this paper. A simple but new iterative multiuser detection framework is proposed, which consists of a message passing algorithm (MPA) based multiuser detector and a soft-input soft-output (SISO) successive cancellation (SC) polar decoder.
Hang Mu +5 more
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Iterative multiuser receiver in sparse code multiple access systems
2015 IEEE International Conference on Communications (ICC), 2015Sparse code multiple access (SCMA) is a novel non-orthogonal multiple access scheme, in which multiple users access the same channel with user-specific sparse codewords. In this paper, we consider an uplink SCMA system employing channel coding, and develop an iterative multiuser receiver which fully utilizes the diversity gain and coding gain in the ...
Yiqun Wu, Shunqing Zhang, Yan Chen
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Multi-User Detections for Sparse Code Multiple Access System
2018 IEEE 88th Vehicular Technology Conference (VTC-Fall), 2018This paper proposes a new multi-user detection scheme for sparse code multiple access (SCMA) system in grant- free scenario. SCMA systems use a message passing algorithm which considers all user equipments (UEs) to be active. However, in a practical system, UEs do not always request resources.
Joonki Kim, Daesik Hong
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Design and analysis of irregular sparse code multiple access
2015 International Conference on Wireless Communications & Signal Processing (WCSP), 2015Sparse Code Multiple Access (SCMA) is an excellent approach to support massive connections and short time-delay, which are the two key requirements in the future fifth generation (5G) communication system. Due to the drawback that traditional SCMA can't serve users with different business needs in the same scenario, we propose an irregular Sparse Code ...
Shutian Zhang +4 more
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Performance Analysis of Sparse Code Multiple Access MIMO Systems
2019 IEEE 30th Annual International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC), 2019This paper addresses the implementation and performance analysis of sparse code multiple access (SCMA)-multiple–input multiple–output (MIMO) systems. SCMA is a promising technology to accommodate the ever–increasing number of users as well as spectral and bandwidth efficiency enhancements for next generations wireless systems.
Salma Elkawafi +2 more
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Outage Performance of Relay Sparse Code Multiple Access Networks
2019 IEEE Wireless Communications and Networking Conference (WCNC), 2019This paper presents a downlink multi-user network model based on sparse code multiple access (SCMA), where two phases cooperative transmission strategy is introduced to reduce the average outage probability. Motivated by the fact that the reliability is an important indicator in the next generation mobile communication system.
Yibo Zhang +4 more
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Hardware Design and Implementation of Sparse Code Multiple Access
2017 IEEE 86th Vehicular Technology Conference (VTC-Fall), 2017Sparse code multiple access (SCMA) has recently emerged as one of the most favorable multiple access schemes for 5G networks, which allows overloading with a large number of users so as to enable massive connectivity. In this paper, we design a hardware framework of a uplink system for SCMA.
Yunfei Wu +4 more
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Improved Message Passing Algorithms for Sparse Code Multiple Access
IEEE Transactions on Vehicular Technology, 2017Sparse code multiple access (SCMA) is one of the nonorthogonal multiple access techniques for the 5G system. SCMA can provide different levels of overloading to meet the diverse traffic connectivity requirements. However, its relatively high computational complexity of multiuser detection is still a significant concern for practical implementation ...
Jincheng Dai +3 more
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Doubly irregular sparse code multiple access with EXIT analysis
2018 International Conference on Signals and Systems (ICSigSys), 2018Sparse Code Multiple Access (SCMA) is one of the potential candidates of multiple access technique to support future networks. This paper proposes doubly irregular SCMA (DI-SCMA) to increase the user capacity of massive wireless networks. The idea is coming from the fact that successive interference cancellation (SIC) works better when the degree ...
Iswahyudi Hidayat +4 more
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