Comparison of PAM-6 Modulations for Short-Reach Fiber-Optic Links with Intensity Modulation and Direct Detection

TL;DR

This paper compares PAM-6 modulation schemes for short-reach fiber-optic links using intensity modulation and direct detection, demonstrating that probabilistically-shaped PAM-6 outperforms conventional methods under peak power constraints.

Contribution

It introduces a comparison of PAM-6 modulation techniques, highlighting the advantages of probabilistic shaping for improved performance in short-reach fiber-optic links.

Findings

Probabilistically-shaped PAM-6 outperforms conventional cross QAM-32.

Shaped PAM-6 achieves better power efficiency.

Experimental results confirm the benefits of probabilistic shaping.

Abstract

PAM-6 transmission is considered for short-reach fiber-optic links with intensity modulation and direct detection. Experiments show that probabilistically-shaped PAM-6 and a framed-cross QAM-32 constellation outperform conventional cross QAM-32 under a peak power constraint.