Downlink Non-Orthogonal Multiple Access Without SIC for Block Fading Channels: An Algebraic Rotation Approach

Min Qiu*, Yu-Chih Huang, Jinhong Yuan

*Corresponding author for this work

Research output: Contribution to journalArticle

Abstract

In this paper, we investigate the problem of downlink non-orthogonal multiple access (NOMA) over block fading channels. For the single antenna case, we propose a class of NOMA schemes where all the users' signals are mapped into n-dimensional constellations corresponding to the same algebraic lattices from a number field, allowing every user attains full diversity gain with single-user decoding, i.e., no successive interference cancellation (SIC). The minimum product distances of the proposed scheme with arbitrary power allocation factor are analyzed and their upper bounds are derived. Within the proposed class of schemes, we also identify a special family of NOMA schemes based on lattice partitions of the underlying ideal lattices, whose minimum product distances can he easily controlled. Our analysis shows that among the proposed schemes, the lattice partition based schemes achieve the largest minimum product distances of the superimposed constellations, which are closely related to the symbol error rates for receivers with single-user decoding. The simulation results are presented to verify our analysis and to show the effectiveness of the proposed schemes as compared to benchmark NOMA schemes. Extensions of our design to the multi-antenna case are also considered where similar analysis and results are presented.

Original languageEnglish
Pages (from-to)3903-3918
Number of pages16
JournalIEEE Transactions on Wireless Communications
Volume18
Issue number8
DOIs
StatePublished - Aug 2019

Keywords

  • Non-orthogonal multiple access (NOMA)
  • block fading
  • modulations
  • diversity
  • space-time codes
  • CHALLENGES
  • MODULATION

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