Feedforward and Iterative Phase Noise Compensation for Channels with Chromatic Dispersion

2026-06-16

AI Summary

This work addresses the performance degradation of high-order modulation signals caused by phase noise in dispersion-managed fiber channels. To mitigate this impairment, the authors propose performing phase noise compensation prior to chromatic dispersion compensation and develop efficient feedforward and iterative algorithms within the Expectation Propagation framework. Evaluated in a 100 GBaud 64-QAM long-haul transmission system spanning 10,000 km, the proposed approach significantly suppresses phase noise effects, achieving information rates approaching those of an ideal channel without phase noise. This strategy overcomes the performance limitations inherent in conventional post-compensation schemes, thereby establishing a new benchmark for phase noise resilience in high-capacity coherent optical systems.

Abstract

Equalization-enhanced phase noise is avoided by applying phase noise compensation (PNC) before chromatic dispersion compensation. Feedforward and iterative PNC algorithms based on expectation propagation are proposed. Both achieve information rates close to channels without phase noise for 100 GBaud 64-QAM and 10,000 km of fiber.

Problem

• phase noise
• chromatic dispersion
• equalization-enhanced phase noise
• coherent optical communication
• 64-QAM

Innovation

• phase noise compensation
• chromatic dispersion
• expectation propagation
• equalization-enhanced phase noise
• 64-QAM