Results 171 to 180 of about 1,654 (206)

Design of Codebook for High Overload SCMA

2020
With the development of mobile communication and multiple access technology, SCMA (Sparse Code Division Multiple Access) technology, as a new access technology, can improve the overload rate, gain coding gain and maintain low complexity because of the limited spectrum resources in the new demand scenario.
Min Jia 0001, Shiyao Meng, Qing Guo 0001, Xuemai Gu   +3 more
openaire   +1 more source

User capacity for uplink SCMA system

Physical Communication, 2020
Abstract Sparse Code Multiple Access (SCMA) is a non-orthogonal multiple access (NOMA) scheme which allows multi-user communication with massive connectivity. In this paper, we consider an uplink SCMA network of limited resources (time/frequency/power). We seek to answer the following question: what is the maximum number of users that can be admitted
Doaa Gamal, Ahmed Hesham Mehana, Khaled M. F. Elsayed   +2 more
openaire   +1 more source

BER Performance of Multicast SCMA Systems

IEEE Wireless Communications Letters, 2019
Sparse code multiple access (SCMA) and wireless multicast are viewed as two effective techniques to improve spectral efficiency. Due to the diversity of channel gains for different receivers in the multicast group, the bit error rate (BER) analysis of the unicast SCMA is not suitable for the multicast SCMA systems.
Yibo Zhang 0005, Xiaoxiang Wang, Dongyu Wang, Yufang Zhang, Yanwen Lan   +4 more
openaire   +1 more source

A Linear Complexity SCMA Detection Algorithm

2020 IEEE 20th International Conference on Communication Technology (ICCT), 2020
Sparse Code Multiple Access (SCMA) is a promising non-orthogonal multiple access scheme. Although message passing algorithm (MPA) can reduce the detection complexity exploiting the sparsity of SCMA, it is still exponential order. Excessive detection complexity is a major obstacle to SCMA engineering applications.
Chengxin Jiang, Yafeng Wang
openaire   +1 more source

System-level performance estimation of SCMA

2016 IEEE International Conference on Communication Systems (ICCS), 2016
Sparse code multiple access (SCMA) is a novel non-orthogonal multiple access technique, which enjoys the low complexity of message passing algorithm (MPA) and the shaping gain of multidimensional codewords. The performance of SCMA is usually evaluated by the system level simulation and represented by the block error rate (BLER) as a metric.
Ce Sun, Lei Li 0030, Jianqiang Chen, Dai Jia, Hanxiao Yu, Jingxuan Huang, Zesong Fei   +6 more
openaire   +1 more source

RBF-SCMA: Faster Machine Learning Based SCMA

ICC 2022 - IEEE International Conference on Communications, 2022
Ameya Vikram, Ekagra Ranjan, Alentattil Rajesh, Prabin Kumar Bora   +3 more
openaire   +1 more source

Low Complexity Techniques for SCMA Detection

2015 IEEE Globecom Workshops (GC Wkshps), 2015
Sparse code multiple access (SCMA) is a codebook- based non-orthogonal multiplexing technique. In SCMA, the procedure of bit to QAM symbol mapping and spreading of CDMA are combined together and incoming bits are directly mapped to multi-dimensional codewords of SCMA codebook sets.
Alireza Bayesteh, Hosein Nikopour, Mahmoud Taherzadeh, Hadi Baligh, Jianglei Ma   +4 more
openaire   +1 more source

AFDM-SCMA: A Promising Waveform for Massive Connectivity Over High Mobility Channels

IEEE Transactions on Wireless Communications
This paper studies the affine frequency division multiplexing (AFDM)-empowered sparse code multiple access (SCMA) system, referred to as AFDM-SCMA, for supporting massive connectivity in high-mobility environments.
Qu Luo, Pei Xiao, Zilong Liu
exaly   +2 more sources

On the performance evaluation of MIMO-SCMA systems

2016 8th International Congress on Ultra Modern Telecommunications and Control Systems and Workshops (ICUMT), 2016
Massive multiple-input multiple-output (MIMO) systems is an emerging technology that is paving its way into wireless communication systems. Massive MIMO consists of tens or hundreds of antennas, which will result in an increase in capacity, reliability and performance.
Wissam Abdessamad, Youssef Nasser, Karim Y. Kabalan, Oussama Bazzi   +3 more
openaire   +1 more source

A Novel HARQ Scheme for SCMA Systems

IEEE Wireless Communications Letters, 2016
This letter considers the hybrid automatic repeat request (HARQ) scheme for sparse code multiple access (SCMA) systems, where the message passing algorithm (MPA) is adopted in the multiuser detection. In MPA, the reliability can be improved when parts of messages are pre-known.
Yin Long, Zhi Chen 0002, Zhiwu Guo, Jun Fang 0001   +3 more
openaire   +1 more source