Field trial over 820 km installed SSMF and its potential Terabit/s superchannel application with up to 57.5-Gbaud DP-QPSK transmission

• Published in: Optics communications Vol. 353; pp. 133 - 138
• Main Authors: Xu, Tianhua, Li, Jie, Jacobsen, Gunnar, Popov, Sergei, Djupsjöbacka, Anders, Schatz, Richard, Zhang, Yimo, Bayvel, Polina
• Format: Journal Article
• Language: English
• Published: 15.10.2015
• Subjects: Coherent optical transmission Digital signal processing Field trial Optical fiber communication Quadrature phase shift keying
• ISSN: 0030-4018; 1873-0310
• DOI: 10.1016/j.optcom.2015.05.029

In this paper, we report the result of a field trial of 56-Gbaud (224-Gbit/s) and 57.5-Gbaud (230-Gbit/s) dual-polarization quadrature phase shift keying (DP-QPSK) coherent optical transmission over 820 km installed standard single mode fiber (SSMF). Offline digital signal processing (DSP) was applied for signal recovery and bit-error-rate (BER) counting in our field trial experiments, and BER performance well below the 7% overhead hard-decision forward error correction (FEC) error-free threshold (4.5×10-3) at 231-1 pseudo random bit sequence (PRBS) pattern length has been achieved, with the best achievable BERs of 2×10-4 (56-Gbaud) and 3×10-4 (57.5-Gbaud), respectively. In parallel a 1.15-Tbit/s (5×230-Gbit/s) quasi-Nyquist spaced wavelength division multiplexing (WDM) superchannel transmission over the same 820 km optical field link (FL) was also investigated through numerical simulations based on the same 57.5-Gbaud DP-QPSK signal using 1% roll-off Nyquist pulse shaping with 60-GHz channel spacing, and the results indicate that the BER performance well below the 7% overhead hard-decision FEC error-free threshold (4.5×10-3) for the 1.15-Tbit/s DP-QPSK superchannel transmission can be achieved.