Low-Complexity Adaptive Digital Backpropagation via Clock-Tone Strength in Coherent Optical Systems

We propose a low-complexity clock-tone-guided adaptive digital backpropagation (ADBP) that self-tunes the nonlinear coefficient. Over a 1200-km link, it achieves comparable performance while reducing complexity by 52.9% and 45.4% relative to phase-variance and intensity-noise-variance ADBP.