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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 19, Iss. 19 — Sep. 12, 2011
  • pp: 18655–18664

Experimental analysis of singularity-avoidance techniques for CMA equalization in DP-QPSK 112-Gb/s optical systems

Valery N. Rozental, Thiago F. Portela, Diego V. Souto, Hugo B. Ferreira, and Darli A. A. Mello  »View Author Affiliations

Optics Express, Vol. 19, Issue 19, pp. 18655-18664 (2011)

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We experimentally investigate the singularity problem in DP-QPSK 112-Gb/s receivers using the CMA. Three algorithms are compared: Constrained, Two-Stage, and Multi-User. Although these algorithms have been individually evaluated, they have not been compared by extensive experiments. The transmission setup emulates amplifier noise; first-order PMD; and chromatic dispersion. It is shown that all algorithms effectively mitigate singularities. However, under certain conditions, the Multi-User and the Constrained algorithms – both used for system startup – outperformed the Two-Stage, which does not distinguish between system operation and startup. In light of its effectiveness and low computational complexity, we recommend the Constrained algorithm.

© 2011 OSA

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

ToC Category:
Fiber Optics and Optical Communications

Original Manuscript: June 17, 2011
Revised Manuscript: July 28, 2011
Manuscript Accepted: August 14, 2011
Published: September 9, 2011

Valery N. Rozental, Thiago F. Portela, Diego V. Souto, Hugo B. Ferreira, and Darli A. A. Mello, "Experimental analysis of singularity-avoidance techniques for CMA equalization in DP-QPSK 112-Gb/s optical systems," Opt. Express 19, 18655-18664 (2011)

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