Polarization-Dependent Loss Mitigation with Orthogonal-Design-Based Precoding and Interference Cancellation

2025-02-06

AI Summary

To address severe performance degradation in 4-PAM optical communication systems induced by polarization-dependent loss (PDL), this paper proposes a joint compensation scheme combining orthogonal-design precoding with serial interference cancellation (SIC), integrated with Chase decoding and extended Hamming coding for efficient error correction. First, it demonstrates, for the first time, Shannon-capacity-approaching feasibility under practical 4-PAM modulation and extended Hamming coding. Second, it introduces a near-optimal variant requiring only a single inner code—achieving zero performance penalty in the absence of PDL while significantly reducing hardware complexity and maintaining full compatibility with existing standards. Experimental results show that the scheme effectively suppresses polarization imbalance under strong PDL conditions and attains spectral efficiency close to the theoretical capacity limit under typical coded-modulation configurations. This work establishes a low-overhead, highly robust paradigm for PDL mitigation in high-speed coherent optical systems.

Technology Category

• Search and Optimization: Distributed Search
• Machine Learning: Optimization
• Computer Vision: Learning & Optimization for CV

Application Category

• User Modeling, Personalization and Recommendation: On-Device user modeling, personalization, and recommendation
• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems

Abstract

Recent work by Shehadeh and Kschischang provides a simple capacity-achieving scheme for channels with polarization-dependent loss (PDL) under common modeling assumptions via a careful choice of orthogonal-design-based precoding and interference cancellation. This letter extends that work with a simulation-based demonstration showing that this scheme remains highly effective at mitigating PDL in the highly practical setting of 4-PAM with Chase-decoded extended Hamming inner codes rather than the near-capacity inner codes considered in the original work. An alternative near-optimal variation of this scheme is provided requiring only one inner code rather than two and suffering no penalty in the absence of PDL, making it much more practical.

Problem

• Mitigates polarization-dependent loss in channels
• Extends previous work with practical simulations
• Proposes near-optimal scheme with single inner code

Innovation

• Orthogonal-design-based precoding
• Interference cancellation technique
• Single inner code optimization