Results 241 to 250 of about 30,188 (287)
Some of the next articles are maybe not open access.
Sparse Code Multiple Access Over Universal Filtered Multicarrier
IEEE Transactions on Vehicular Technology, 2021In this paper, the uplink sparse code multiple access over universal filtered multicarrier (SCMA-UFMC) is studied. In SCMA-UFMC, each sub-band of UFMC is occupied by multiple users through SCMA. Note that the even-component of frequency domain (FD) received signal suffers from neither inter-sub-band interference nor inter-sub-carrier interference while
Changju Chen, Jianping Zheng, Fuping Si
openaire +1 more source
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 +3 more
openaire +1 more source
Sparse Code Multiple Access (SCMA)
2018Sparse Code Multiple Access (SCMA) enables non-orthogonal transmissions of multiple users’ signals among code and power domain, which could greatly improve the spectral efficiency. Due to the sparsity of the multi-dimensional codewords, the low-complexity message-passing algorithm (MPA) can be adopted and near maximum likelihood (ML) performance for ...
Zheng Ma, Jinchen Bao
openaire +1 more source
Sparse Code and Hybrid Multiple Access Techniques
2020Next-generation wireless networks require higher spectral efficiency and lower latency to meet the demands of various upcoming applications. Recently, non-orthogonal multiple access (NOMA) schemes are introduced in the literature for 5G and beyond. Various forms of NOMA are considered like power domain, code domain, pattern division multiple access ...
Sanjeev Sharma, Kuntal Deka
openaire +1 more source
Fractional Sparse Code Multiple Access and Its Optimization
IEEE Wireless Communications Letters, 2018This letter proposes a fractional sparse code multiple access (FrSCMA) system in which each user directly maps a varying number of error-correction coded symbols onto the resource elements per channel use. The dynamic sparse mapping leads to a fractional spreading factor, often smaller than that in the existing multidimensional constellation (MDC ...
Yicheng Wang +4 more
openaire +1 more source
Sparse Code Multiple Access Scheme Based on Variational Learning
IEEE Transactions on Communications, 2022Sparse code multiple access (SCMA) technology has been widely studied thanks to its outstanding overload performance, which provides greater device access on limited time-frequency resources. We propose a variational learning based end-to-end SCMA network model termed as V-SCMA.
Quan Yuan +4 more
openaire +2 more sources
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
openaire +1 more source
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.
openaire +1 more source
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 +3 more
openaire +1 more source
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
openaire +1 more source