Technical feasibility of a 400 Gb/s unamplified WDM coherent transmission system for ethernet over 40 km of single-mode fiber

The proposal, analysis and technical feasibility of a 4 × 100 Gb/s 40-km coherent optical system over single-mode fiber for next generation Ethernet data transmission are presented. The link is based on a 100 GHz-spaced channel plan on C-band that employs DP-QPSK as advanced modulation format. Typical coherent transmitters and receivers with state-of-the-art digital signal processing functionalities are considered, avoiding the use of any type of optical amplification or forward error correction. According to the analysis, an optical transmitter power per channel between -5.6 dBm and -1.0 dBm guarantees the error-free operation (BER > 1×10^-13) of the 40-km transmission link. Further system details are also presented. This simulation work leverages the use of coherent technology at metro network level.