OSA's Digital Library

Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 20, Iss. 26 — Dec. 10, 2012
  • pp: B171–B180

Ultrafast and low overhead training symbol based channel estimation in coherent M-QAM single-carrier transmission systems

Mohamed Morsy-Osman, Mathieu Chagnon, Qunbi Zhuge, Xian Xu, Mohammad E. Mousa-Pasandi, Ziad A. El-Sahn, and David V. Plant  »View Author Affiliations


Optics Express, Vol. 20, Issue 26, pp. B171-B180 (2012)
http://dx.doi.org/10.1364/OE.20.00B171


View Full Text Article

Enhanced HTML    Acrobat PDF (1182 KB)





Browse Journals / Lookup Meetings

Browse by Journal and Year


   


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools

Share
Citations

Abstract

We propose a training symbol based channel estimation (TS-EST) algorithm that estimates the 2 × 2 Jones channel matrix. The estimated matrix entries are then used as the initial center taps of the 2 × 2 butterfly equalizer. Employing very few training symbols for TS-EST, ultrafast polarization tracking is achieved and tap update can be initially pursued using the decision-directed least mean squares (DD-LMS) algorithm to mitigate residual intersymbol interference (ISI). We experimentally verify the proposed TS-EST algorithm for 112 Gbps PDM-QPSK and 224 Gbps PDM-16QAM systems using 10 and 40 training symbols for TS-EST, respectively. Steady-state and transient bit error rates (BERs) achieved using the TS-EST algorithm are compared to those obtained using the constant modulus algorithm (CMA) and the training symbol least mean squares (TS-LMS) algorithm and results show that the proposed TS-EST algorithm provides the same steady-state BER with a superior convergence speed. Also, the tolerance of the proposed TS-EST algorithm to laser phase noise and fiber nonlinearity is experimentally verified. Finally, we show by simulation that the superior tracking speed of the TS-EST algorithm allows not only for initial polarization tracking but also for tracking fast polarization transients if four training symbols are periodically sent during steady-state operation with an overhead as low as 0.57%.

© 2012 OSA

OCIS Codes
(060.1660) Fiber optics and optical communications : Coherent communications
(060.2330) Fiber optics and optical communications : Fiber optics communications

ToC Category:
Subsystems for Optical Networks

History
Original Manuscript: October 2, 2012
Revised Manuscript: November 8, 2012
Manuscript Accepted: November 8, 2012
Published: November 28, 2012

Virtual Issues
European Conference on Optical Communication 2012 (2012) Optics Express

Citation
Mohamed Morsy-Osman, Mathieu Chagnon, Qunbi Zhuge, Xian Xu, Mohammad E. Mousa-Pasandi, Ziad A. El-Sahn, and David V. Plant, "Ultrafast and low overhead training symbol based channel estimation in coherent M-QAM single-carrier transmission systems," Opt. Express 20, B171-B180 (2012)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-20-26-B171


Sort:  Author  |  Year  |  Journal  |  Reset  

References

  1. K. Roberts, D. Beckett, D. Boertjes, J. Berthold, and C. Laperle, “100G and beyond with digital coherent signal processing,” IEEE Commun. Mag.48(7), 62–69 (2010). [CrossRef]
  2. P. J. Winzer, “Beyond 100G Ethernet,” IEEE Commun. Mag.48(7), 26–30 (2010). [CrossRef]
  3. X. Liu, S. Chandrasekhar, X. Chen, P. J. Winzer, Y. Pan, T. F. Taunay, B. Zhu, M. Fishteyn, M. F. Yan, J. M. Fini, E. M. Monberg, and F. V. Dimarcello, “1.12-Tb/s 32-QAM-OFDM superchannel with 8.6-b/s/Hz intrachannel spectral efficiency and space-division multiplexed transmission with 60-b/s/Hz aggregate spectral efficiency,” Opt. Express19(26), B958–B964 (2011). [CrossRef] [PubMed]
  4. S. Chandrasekhar and X. Liu, “Experimental investigation on the performance of closely spaced multi-carrier PDM-QPSK with digital coherent detection,” Opt. Express17(24), 21350–21361 (2009). [CrossRef] [PubMed]
  5. S. J. Savory, “Digital coherent optical receivers: algorithms and subsystems,” IEEE J. Sel. Top. Quantum Electron.16(5), 1164–1179 (2010). [CrossRef]
  6. E. Ip and J. M. Kahn, “Fiber impairment compensation using coherent detection and digital signal processing,” J. Lightwave Technol.28(4), 502–519 (2010). [CrossRef]
  7. E. Ip, A. P. Lau, D. J. Barros, and J. M. Kahn, “Coherent detection in optical fiber systems,” Opt. Express16(2), 753–791 (2008). [CrossRef] [PubMed]
  8. M. G. Taylor, “Coherent detection method using DSP for demodulation of signal and subsequent equalization of propagation impairments,” IEEE Photon. Technol. Lett.16(2), 674–676 (2004). [CrossRef]
  9. E. Ip and J. M. Kahn, “Compensation of dispersion and nonlinear impairments using digital backpropagation,” J. Lightwave Technol.26(20), 3416–3425 (2008). [CrossRef]
  10. G. Li, “Recent advances in coherent optical communication,” Adv. Opt. Photon.1(2), 279–307 (2009). [CrossRef]
  11. S. J. Savory, “Digital filters for coherent optical receivers,” Opt. Express16(2), 804–817 (2008). [CrossRef] [PubMed]
  12. P. J. Winzer, A. H. Gnauck, C. R. Doerr, M. Magarini, and L. L. Buhl, “Spectrally efficient long-haul optical networking using 112-Gb/s polarization-multiplexed 16-QAM,” J. Lightwave Technol.28(4), 547–556 (2010). [CrossRef]
  13. L. Liu, Z. Tao, W. Yan, S. Oda, T. Hoshida, and J. C. Rasmussen, “Initial tap setup of constant modulus algorithm for polarization de-multiplexing in optical coherent receivers,” in Optical Fiber Communication Conference, OSA Technical Digest (Optical Society of America, 2009), paper OMT2.
  14. G. Agrawal, Lightwave Technology: Telecommunication Systems (Wiley & Sons, 2005), Chap. 3.
  15. M. Morsy-Osman, M. Chagnon, Q. Zhuge, X. Xu, M. E. Mousa-Pasandi, Z. A. El-Sahn, and D. V. Plant, “Training symbol based channel estimation for ultrafast polarization demultiplexing in coherent single-carrier transmission systems with M-QAM constellations,” in Proceedings of European Conference and Exhibition on Optical Communication 2012, paper Mo.1A.4.
  16. M. G. Taylor, “Phase estimation methods for optical coherent detection using digital signal processing,” J. Lightwave Technol.27(7), 901–914 (2009). [CrossRef]
  17. P. Ciblat and M. Ghogho, “Blind NLLS carrier frequency-offset estimation for QAM, PSK, and PAM modulations: performance at low SNR,” IEEE Trans. Commun.54(10), 1725–1730 (2006). [CrossRef]
  18. W. Shieh and K. P. Ho, “Equalization-enhanced phase noise for coherent-detection systems using electronic digital signal processing,” Opt. Express16(20), 15718–15727 (2008). [CrossRef] [PubMed]
  19. Q. Zhuge, X. Xu, Z. A. El-Sahn, M. E. Mousa-Pasandi, M. Morsy-Osman, M. Chagnon, M. Qiu, and D. V. Plant, “Experimental investigation of the equalization-enhanced phase noise in long haul 56 Gbaud DP-QPSK systems,” Opt. Express20(13), 13841–13846 (2012). [CrossRef] [PubMed]
  20. I. Fatadin, D. Ives, and S. J. Savory, “Blind equalization and carrier phase recovery in a 16-QAM optical coherent system,” J. Lightwave Technol.27(15), 3042–3049 (2009). [CrossRef]
  21. L. Nelson, “Polarization effects in coherent systems,” in Optical Fiber Communication Conference, OSA Technical Digest (Optical Society of America, 2012), paper OTu1A.4.
  22. L. Nelson, M. Birk, S. L. Woodward, and P. Magill, “Field measurements of polarization transients on a long-haul terrestrial link,” in Proceedings of IEEE Photonics Conference 2011, paper ThT5.

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

Figures

Fig. 1 Fig. 2 Fig. 3
 
Fig. 4 Fig. 5
 

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited