Iterative near maximum-likelihood sequence detection for MIMO optical wireless systems

Nestor D. Chatzidiamantis, Murat Uysal, T. A. Tsiftsis, G. K. Karagiannidis

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

A major performance-limiting factor in terrestrial optical wireless (OW) systems is turbulence-induced fading. Exploiting the additional degrees of freedom in the spatial dimension, multiple laser transmitters combined with multiple receive apertures provide an effective solution for fading mitigation. Although multiple-input multiple-output (MIMO) OWsystems have been extensively studied in recent years, most of these works are mainly limited to symbol-by-symbol decoding. MLSD exploits the temporal correlation of turbulence-induced fading and promises further performance gains. In this paper, we investigate MLSD for intensity-modulation/direct-detection MIMO OW systems over log-normal atmospheric turbulence channels. Even with a low-order modulation scheme such as OOK, which is typically used inOWsystems, the complexity ofMLSD might be prohibitive. e therefore present an iterative sequence detector based on the expectation-maximization (EM) algorithm. The complexity of the proposed algorithm is considerably less than a direct evaluation of the log-likelihood function, and it is independent of the channel'a fading statistics. The Monte Carlo simulation results demonstrate that the EM-based algorithm outperforms the symbol-by-symbol decoder and achieves a performance, which lies within 0.3 dB of that of the optimal MLSD.

Original languageEnglish
Pages (from-to)1064-1070
Number of pages7
JournalJournal of Lightwave Technology
Volume28
Issue number7
DOIs
Publication statusPublished - 2010
Externally publishedYes

Fingerprint

MIMO (control systems)
fading
turbulence
modulation
decoders
atmospheric turbulence
decoding
transmitters
degrees of freedom
apertures
statistics
evaluation
detectors
lasers
simulation

Keywords

  • Atmospheric turbulence
  • Expectation maximization (EM) algorithm
  • Free-space optical communication
  • Maximum-likelihood (ML) symbol-by-symbol detection
  • MLSD
  • Spatial diversity

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

Cite this

Chatzidiamantis, N. D., Uysal, M., Tsiftsis, T. A., & Karagiannidis, G. K. (2010). Iterative near maximum-likelihood sequence detection for MIMO optical wireless systems. Journal of Lightwave Technology, 28(7), 1064-1070. https://doi.org/10.1109/JLT.2009.2038724

Iterative near maximum-likelihood sequence detection for MIMO optical wireless systems. / Chatzidiamantis, Nestor D.; Uysal, Murat; Tsiftsis, T. A.; Karagiannidis, G. K.

In: Journal of Lightwave Technology, Vol. 28, No. 7, 2010, p. 1064-1070.

Research output: Contribution to journalArticle

Chatzidiamantis, ND, Uysal, M, Tsiftsis, TA & Karagiannidis, GK 2010, 'Iterative near maximum-likelihood sequence detection for MIMO optical wireless systems', Journal of Lightwave Technology, vol. 28, no. 7, pp. 1064-1070. https://doi.org/10.1109/JLT.2009.2038724
Chatzidiamantis, Nestor D. ; Uysal, Murat ; Tsiftsis, T. A. ; Karagiannidis, G. K. / Iterative near maximum-likelihood sequence detection for MIMO optical wireless systems. In: Journal of Lightwave Technology. 2010 ; Vol. 28, No. 7. pp. 1064-1070.
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