Thursday, June 25, 2015

ZTE and OFS Mark 400 Gbps Optical Transmission Record

ZTE and OFS achieved a new record for 400 Gbps optical transmission by carrying 128.8-GBaud wavelength division multiplexing (WDM) QPSK signals over 10,130- and 6,078-kilometer terrestrial fiber links.

Specifically, the tests transmitted single-carrier 515.2-Gb/s polarization division multiplexing (PDM)-QPSK/9-QAM signals over 10,130km and 6,078km links of OFS TeraWave optical fiber. It was the highest ETDM-based symbol rate reported so far, and the longest WDM transmission distance of single-carrier 400G signals with terrestrial span lengths (100km). For the first time, the 515.2-Gb/s single-carrier PDM-QPSK signals in 200-GHz-grid are successfully transmitted over distances over 10,000km in a terrestrial transmission environment. Researchers have also demonstrated the transmission of single carrier 128.8-GBaud filtered QPSK signals in 100-GHz-grid over 6,078km, which has the line SE of 5.152b/s/Hz.

ZTE said this result sets a new record for 400G transmission in both symbol rate and distance. The milestone, published recently on Optics Express (OSA), surpasses the record last year of 110 GBaud over 3000 km transmission distance of 400G set by the same group from ZTE.

According to Dr. Jianjun Yu, the Chief Scientist on high-speed optical transmission at ZTE and OSA Fellow, “400G transmission on a single optical carrier emerged as an attractive solution since it would offer benefits in terms of system complexity. Namely, the employment of the highest feasible electronic multiplexing rates with a minimum number of channel subcarriers reduces the number of deployed optical components, which typically dominates the transponder cost. ZTE has been relentless in pushing forward-looking research and development on the single carrier 400G transmissions, and we have solved most of key technologies for this 400G product.”