Performance Analysis and Approximate Message Passing Detection of Orthogonal Time Sequency Multiplexing Modulation

Zeping Sui, Shefeng Yan*, Hongming Zhang, Sumei Sun, Yonghong Zeng, Lie Liang Yang, Lajos Hanzo

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)

Abstract

In orthogonal time sequency multiplexing (OTSM) modulation, the information symbols are conveyed in the delay-sequency domain upon exploiting the inverse Walsh Hadamard transform (IWHT). It has been shown that OTSM is capable of attaining a bit error ratio (BER) similar to that of orthogonal time-frequency space (OTFS) modulation at a lower complexity, since the saving of multiplication operations in the IWHT. Hence we provide its BER performance analysis and characterize its detection complexity. We commence by deriving its generalized input-output relationship and its unconditional pairwise error probability (UPEP). Then, its BER upper bound is derived in closed form under both ideal and imperfect channel estimation conditions, which is shown to be tight at moderate to high signal-to-noise ratios (SNRs). Moreover, a novel approximate message passing (AMP) aided OTSM detection framework is proposed. Specifically, to circumvent the high residual BER of the conventional AMP detector, we proposed a vector AMP-based expectation-maximization (VAMP-EM) detector for performing joint data detection and noise variance estimation. The variance auto-tuning algorithm based on the EM algorithm is designed for the VAMP-EM detector to further improve the convergence performance. The simulation results illustrate that the VAMP-EM detector is capable of striking an attractive BER vs. complexity trade-off than the state-of-the-art schemes as well as providing a better convergence. Finally, we propose AMP and VAMP-EM turbo receivers for low-density parity-check (LDPC)-coded OTSM systems. It is demonstrated that our proposed VAMP-EM turbo receiver is capable of providing both BER and convergence performance improvements over the conventional AMP solution.

Original languageEnglish
Pages (from-to)1913-1928
Number of pages16
JournalIEEE Transactions on Wireless Communications
Volume23
Issue number3
DOIs
Publication statusPublished - 1 Mar 2024
Externally publishedYes

Keywords

  • Orthogonal time-frequency space (OTFS)
  • approximate message passing (AMP)
  • expectation-maximization (EM)
  • orthogonal time sequency multiplexing (OTSM)
  • turbo receiver

Fingerprint

Dive into the research topics of 'Performance Analysis and Approximate Message Passing Detection of Orthogonal Time Sequency Multiplexing Modulation'. Together they form a unique fingerprint.

Cite this