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Sparse Code Multiple Access with Index Modulation
2020 IEEE/CIC International Conference on Communications in China (ICCC), 2020In this paper, we study the application of index modulation (IM) to uplink sparse code multiple access (SCMA), and present a scheme called SCMA-IM. In the proposed SCMA-IM, the candidate resources of one user are partitioned into two groups. All the resources in the first group are utilized to transmit signals, and only part of resources in the second ...
Chen Zuo, Jianping Zheng
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2013 IEEE 24th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC), 2013
Multicarrier CDMA is a multiplexing approach in which modulated QAM symbols are spread over multiple OFDMA tones by using a generally complex spreading sequence. Effectively, a QAM symbol is repeated over multiple tones. Low density signature (LDS) is a version of CDMA with low density spreading sequence allowing us to take advantage of a near optimal ...
Hosein Nikopour, Hadi Baligh
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Multicarrier CDMA is a multiplexing approach in which modulated QAM symbols are spread over multiple OFDMA tones by using a generally complex spreading sequence. Effectively, a QAM symbol is repeated over multiple tones. Low density signature (LDS) is a version of CDMA with low density spreading sequence allowing us to take advantage of a near optimal ...
Hosein Nikopour, Hadi Baligh
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An Improved Uplink Sparse Coded Multiple Access
IEEE Communications Letters, 2017Sparse coded multiple access (SCMA) has received considerable attention recently as a candidate multiple access scheme for 5G cellular systems. This letter proposes an improved uplink SCMA scheme where instead of the multi-dimensional constellation (MDC) mapping and a fixed number of nonzero elements per sparse codeword, a varying number of coded ...
Ming Zhao 0008 +3 more
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Subcarrier and Power Allocation for Sparse Code Multiple Access
2020 IEEE 91st Vehicular Technology Conference (VTC2020-Spring), 2020Resource allocation for Sparse Code Multiple Access (SCMA) systems is restricted by the codebook design for data transmission from different users simultaneously. The effect of the interference between users assigned to the same resource can result in severe degradation of performance.
Yanely Jimenez Licea +2 more
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Efficient Row-Layered Decoder for Sparse Code Multiple Access
IEEE Transactions on Circuits and Systems I: Regular Papers, 2021Sparse code multiple access (SCMA) is a promising technology for the development of wireless communication, which supports a large number of overloading users and enjoys high spectral efficiency. However, conventional SCMA decoders suffer very high complexity in implementations.
Xu Pang +4 more
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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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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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Sparse code multiple access for downlink multiple access of 5G wireless networks
Computer Communications, 2020Abstract Mobile data traffic as the two main forces for the development of future communications, mobile Internet and Internet of Things give the fifth generation of mobile communications (5G) unlimited possibilities and prospects. A large number of mobile device access and shortage of spectrum resources are also issues that 5G needs to face.
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Sparse Code Multiple Access for 5G Radio Transmission
2017 IEEE 86th Vehicular Technology Conference (VTC-Fall), 2017Non-orthogonal multiple access has been extensively discussed in New Radio (NR), the study item working on 5G air interface in 3GPP. Sparse code multiple access (SCMA) is one of the proposed MA schemes. In this paper, the basic concept of SCMA is introduced, including codebook mapping, multiple access procedure, and advanced receivers. Then, link level
Yiqun Wu 0001 +3 more
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Modified Sphere Decoding for Sparse Code Multiple Access
IEEE Communications Letters, 2018Sparse code multiple access (SCMA), a novel non-orthogonal multiple access scheme for fifth generation wireless, has drawn much attention. Since optimal SCMA detection incurs high computational complexity, we develop a modified single tree search (MSTS) to obtain soft outputs for coded SCMA.
Lanping Li +3 more
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