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Updated: May 1, 2026

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Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
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Performance comparison of spectrum-narrowing equalizations with maximum likelihood sequence estimation and
Optics Express
|March 26, 2014
Summary
This study compares three post-compensation algorithms for mitigating inter-symbol interference in high spectral-efficiency optical systems. A new method generates MLSE output compatible with soft-decision forward error correction.
Area of Science:
- Optical Communications
- Signal Processing
Background:
- Inter-symbol interference (ISI) impairs bandwidth-limited optical signals.
- High spectral-efficiency (SE) optical systems require effective equalization techniques.
Purpose of the Study:
- To comprehensively compare three post-compensation algorithms for ISI mitigation in SE optical systems.
- To introduce a novel approach for generating MLSE output compatible with SD-FEC.
Main Methods:
- Comparison of 1-tap CMA with 3-tap MLSE, regular CMA with 2-tap MLSE, and CMMA with 2-tap MLSE.
- Utilized a unified modeling platform for algorithm analysis.
- Developed and verified a novel method for MLSE hard and soft value generation.
Main Results:
- Provides the first comprehensive analysis of these specific post-compensation algorithms on a single platform.
- Demonstrates the effectiveness of the proposed method for MLSE output generation.
- Highlights the importance of equalization for optical signal integrity.
Conclusions:
- The comparative analysis provides valuable insights for selecting optimal equalization strategies.
- The novel MLSE output generation method enhances compatibility with SD-FEC, improving error correction capabilities.
- Effective ISI mitigation is crucial for advancing high SE optical communication systems.
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