# 11,700 km Transmission at 4.8 bit/4D-sym via Four-dimensional Geometrically-shaped Polarization-Ring-Switching Modulation

## TL;DR

This paper demonstrates a novel four-dimensional modulation format enabling high-capacity optical transmission over ultra-long distances, achieving significant reach improvements with efficient amplification techniques.

## Contribution

Introduction of a geometrically-shaped four-dimensional modulation format that enhances transmission reach and efficiency in optical fiber communications.

## Key findings

- Transmitted 11x200 Gbit/s over 7,925 km with EDFA-only amplification.
- Extended transmission to 11,700 km using hybrid amplification.
- Achieved 16% reach increase over PM-8QAM.

## Abstract

Using a novel geometrically-shaped four-dimensional modulation format, we transmitted 11x200 Gbit/s DWDM at 4.8 bit/4D-sym over 7,925 km and 11,700 km using EDFA-only and hybrid amplification, respectively. A reach increase of 16% is achieved over PM-8QAM.