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Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
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Hybrid constellation entropy loading for adaptively partitioned SSB-DMT systems.
Optics Express
|November 2, 2019
Summary
This study introduces an effective entropy loading (EL) scheme for single sideband discrete multi-tone (SSB-DMT) systems. The proposed hybrid constellation entropy loading (HCEL) with optimal partitioning significantly improves receiver sensitivity for optical transmission.
Area of Science:
- Optical Communications
- Digital Signal Processing
- Information Theory
Background:
- Single sideband discrete multi-tone (SSB-DMT) systems are crucial for high-speed optical communication.
- Entropy loading (EL) is a technique to optimize data transmission by adapting to channel conditions.
- Existing EL methods can be complex and computationally intensive.
Purpose of the Study:
- To propose a practical and effective entropy loading (EL) scheme for SSB-DMT systems.
- To enhance system performance by optimizing probabilistically shaped quadrature amplitude modulation (PS-QAM) constellations.
- To reduce the complexity of EL implementation while maintaining high data rates.
Main Methods:
- Adaptive subcarrier partitioning and precoding.
- Utilizing information bits per symbol (IBPS) to identify optimal PS-QAM.
- Implementing hybrid constellation entropy loading (HCEL) with equally partitioned precoding (EPP) and optimally partitioned precoding (OPP).
- Constraining performance by normalized generalized mutual information (NGMI) of forward error correction (FEC).
Main Results:
- HCEL with OPP significantly reduces the number of distribution matchers to 3.
- Negligible loss in net data rate (NDR) is observed with HCEL.
- HCEL with OPP achieves a 4.4 dB receiver sensitivity gain over conventional methods.
- HCEL with EPP offers a 1.2 dB gain over EPP at 60 Gb/s over 80 km SMF.
Conclusions:
- The proposed HCEL with OPP is a practical and competitive solution for EL in SSB-DMT systems.
- This method offers significant receiver sensitivity improvements for short-to-medium reach optical transmissions.
- The reduced complexity makes this approach suitable for real-world deployment.
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