A robust and low complexity clustering-based blind equalizer for PolMux QAM optical coherent systems



In polarization-multiplexed (PolMux) coherent systems, adaptive blind equalizer is efficient in demultiplexing and mitigating inter-symbol interference. A novel clustering-based blind algorithm is proposed, which has simpler computational requirement than the traditional clustering-based blind algorithms. And furthermore, the variance of Gaussian clusters and step size in the novel algorithm can adjust adaptively in the process of convergence, which means it has excellent robust ability. By simulation in a PolMux-16/64QAM coherent systems, we show that the proposed algorithm outperforms existing blind algorithms.


Coherent optical communication Digital signal processing Blind equalizer Cluster 



This work was partially supported by the National Natural Science Foundation of China (NSFC) (Grant Nos. 61671329, 61201426). The authors would like to thank the reviewers for their valuable suggestion and insightful comments that helped in improving the quality of this manuscript.


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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  • ZhiLi Zhou
    • 1
  • Yiju Zhan
    • 2
  • XiuKai Ruan
    • 3
    • 4
  • Hailiang Li
    • 1
  1. 1.School of Electronics and Information TechnologySun Yat-sen UniversityGuangzhouChina
  2. 2.School of EngineeringSun Yat-sen UniversityGuangzhouChina
  3. 3.College of Physics and Electronic Information EngineeringWenzhou UniversityWenzhouChina
  4. 4.National-Local Joint Engineering Laboratory of Digitalize Electrical Design TechnologyWenzhouChina

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