WDM Field Trial over 764 km SSMF with 16 x 112 Gb/s NRZ-DQPSK co-propagating with 10.7 Gb/s NRZ

A 16x112 Gb/s field trial was performed over the fiber infrastructure of Deutsche Telekom partially with high PMD. Using of 56 Gbaud NRZ-DQPSK format no XPM related penalty could be observed when co-propagating with a 10.7 Gb/s NRZ. Robust Metro DWDM transmission with attractive carrier-grade margins is demonstrated. Introduction The next implemented optical transport hierarchy for Metro and long-haul transmission systems will support 100 Gb/s Ethernet transport as well as Optical Transport Network (OTN) functionality with bitrates of about 112 Gb/s (OTU-4). Various field trials with serial 100 Gb/s transport have been demonstrated with modulation formats having different baud1-5 rates . 100 Gb/s long-haul transmission at 50 GHz channel spacing DP-QPSK together with coherent reception has been recognized as 6 the most promising modulation format . Looking at Metro systems, 100 Gb/s transport on a 100 GHz grid appears cost efficient for network operators requesting systems with low complexity, low power consumption and simple upgradability of existing 10 Gb/s infrastructures. Considering co-propagation with 10 Gb/s NRZ as closest neighboring channels, cross phase modulation (XPM) impairments can become 7 significant even at 100 GHz channel spacing, as XPM strongly depends on the symbol rate (walk-off) of the different channels, the channel power and the dispersion map. In this paper 1.6 Tb/s (16 x 112 Gb/s) fiber transmission on a 100 GHz grid is reported by a DWDM field trial experiment in south Germany over large Metro distances within the installed fiber network of Deutsche Telekom.