Enabling Sphere Decoding for SCMA

Monirosharieh Vameghestahbanati, Ebrahim Bedeer Mohamed, Ian Marsland, Ramy Gohary, Halim Yanikomeroglu

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

In this paper, we propose a reduced-complexity optimal modified sphere decoding (MSD) detection scheme for SCMA. As SCMA systems are characterized by a number of resource elements (REs) that are less than the number of the supported users, the channel matrix is rank-deficient, and sphere decoding (SD) cannot be directly applied. Inspired by the Tikhonov regularization, we formulate a new full-rank detection problem that it is equivalent to the original rank-deficient detection problem for constellation points with constant modulus and an important subset of non-constant modulus constellations. By exploiting the SCMA structure, the computational complexity of MSD is reduced compared with the conventional SD. We also employ list MSD to facilitate channel coding. Simulation results demonstrate that in uncoded SCMA systems the proposed MSD achieves the performance of the optimal maximum likelihood (ML) detection. Additionally, the proposed MSD benefits from a lower average complexity compared with MPA.
LanguageEnglish
Pages2750-2753
JournalIEEE Communications Letters
Volume21
Issue number12
Early online date31 Aug 2017
DOIs
Publication statusPublished - Dec 2017

Fingerprint

Decoding
Channel coding
Maximum likelihood
Computational complexity

Keywords

  • Sparse code multiple access (SCMA)
  • modified list sphere decoding (MSD)
  • maximum likelihood (ML)

Cite this

Vameghestahbanati, M., Mohamed, E. B., Marsland, I., Gohary, R., & Yanikomeroglu, H. (2017). Enabling Sphere Decoding for SCMA. IEEE Communications Letters, 21(12), 2750-2753. https://doi.org/10.1109/LCOMM.2017.2747550
Vameghestahbanati, Monirosharieh ; Mohamed, Ebrahim Bedeer ; Marsland, Ian ; Gohary, Ramy ; Yanikomeroglu, Halim. / Enabling Sphere Decoding for SCMA. In: IEEE Communications Letters. 2017 ; Vol. 21, No. 12. pp. 2750-2753.
@article{a4e70db9d662425a9abca816f7846cb3,
title = "Enabling Sphere Decoding for SCMA",
abstract = "In this paper, we propose a reduced-complexity optimal modified sphere decoding (MSD) detection scheme for SCMA. As SCMA systems are characterized by a number of resource elements (REs) that are less than the number of the supported users, the channel matrix is rank-deficient, and sphere decoding (SD) cannot be directly applied. Inspired by the Tikhonov regularization, we formulate a new full-rank detection problem that it is equivalent to the original rank-deficient detection problem for constellation points with constant modulus and an important subset of non-constant modulus constellations. By exploiting the SCMA structure, the computational complexity of MSD is reduced compared with the conventional SD. We also employ list MSD to facilitate channel coding. Simulation results demonstrate that in uncoded SCMA systems the proposed MSD achieves the performance of the optimal maximum likelihood (ML) detection. Additionally, the proposed MSD benefits from a lower average complexity compared with MPA.",
keywords = "Sparse code multiple access (SCMA), modified list sphere decoding (MSD), maximum likelihood (ML)",
author = "Monirosharieh Vameghestahbanati and Mohamed, {Ebrahim Bedeer} and Ian Marsland and Ramy Gohary and Halim Yanikomeroglu",
year = "2017",
month = "12",
doi = "10.1109/LCOMM.2017.2747550",
language = "English",
volume = "21",
pages = "2750--2753",
journal = "IEEE Communications Letters",
issn = "1089-7798",
number = "12",

}

Vameghestahbanati, M, Mohamed, EB, Marsland, I, Gohary, R & Yanikomeroglu, H 2017, 'Enabling Sphere Decoding for SCMA', IEEE Communications Letters, vol. 21, no. 12, pp. 2750-2753. https://doi.org/10.1109/LCOMM.2017.2747550

Enabling Sphere Decoding for SCMA. / Vameghestahbanati, Monirosharieh; Mohamed, Ebrahim Bedeer; Marsland, Ian; Gohary, Ramy; Yanikomeroglu, Halim.

In: IEEE Communications Letters, Vol. 21, No. 12, 12.2017, p. 2750-2753.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Enabling Sphere Decoding for SCMA

AU - Vameghestahbanati, Monirosharieh

AU - Mohamed, Ebrahim Bedeer

AU - Marsland, Ian

AU - Gohary, Ramy

AU - Yanikomeroglu, Halim

PY - 2017/12

Y1 - 2017/12

N2 - In this paper, we propose a reduced-complexity optimal modified sphere decoding (MSD) detection scheme for SCMA. As SCMA systems are characterized by a number of resource elements (REs) that are less than the number of the supported users, the channel matrix is rank-deficient, and sphere decoding (SD) cannot be directly applied. Inspired by the Tikhonov regularization, we formulate a new full-rank detection problem that it is equivalent to the original rank-deficient detection problem for constellation points with constant modulus and an important subset of non-constant modulus constellations. By exploiting the SCMA structure, the computational complexity of MSD is reduced compared with the conventional SD. We also employ list MSD to facilitate channel coding. Simulation results demonstrate that in uncoded SCMA systems the proposed MSD achieves the performance of the optimal maximum likelihood (ML) detection. Additionally, the proposed MSD benefits from a lower average complexity compared with MPA.

AB - In this paper, we propose a reduced-complexity optimal modified sphere decoding (MSD) detection scheme for SCMA. As SCMA systems are characterized by a number of resource elements (REs) that are less than the number of the supported users, the channel matrix is rank-deficient, and sphere decoding (SD) cannot be directly applied. Inspired by the Tikhonov regularization, we formulate a new full-rank detection problem that it is equivalent to the original rank-deficient detection problem for constellation points with constant modulus and an important subset of non-constant modulus constellations. By exploiting the SCMA structure, the computational complexity of MSD is reduced compared with the conventional SD. We also employ list MSD to facilitate channel coding. Simulation results demonstrate that in uncoded SCMA systems the proposed MSD achieves the performance of the optimal maximum likelihood (ML) detection. Additionally, the proposed MSD benefits from a lower average complexity compared with MPA.

KW - Sparse code multiple access (SCMA)

KW - modified list sphere decoding (MSD)

KW - maximum likelihood (ML)

U2 - 10.1109/LCOMM.2017.2747550

DO - 10.1109/LCOMM.2017.2747550

M3 - Article

VL - 21

SP - 2750

EP - 2753

JO - IEEE Communications Letters

T2 - IEEE Communications Letters

JF - IEEE Communications Letters

SN - 1089-7798

IS - 12

ER -

Vameghestahbanati M, Mohamed EB, Marsland I, Gohary R, Yanikomeroglu H. Enabling Sphere Decoding for SCMA. IEEE Communications Letters. 2017 Dec;21(12):2750-2753. https://doi.org/10.1109/LCOMM.2017.2747550