25 GHz spacing DWDM soliton transmission over 2000 km of SMF with 25 dB/span

A high-density dense wavelength multiplexing (DWDM) dispersion-managed soliton loop experiment at 10 Gbit/s per channel with 25 GHz spacing have been conducted over 100 km/ 25 dB spans of SMF. The 1500 km error-free transmission using EDFA was improved to 2100 km using hybrid Raman/EDFA amplification.