ZTE Communications ›› 2012, Vol. 10 ›› Issue (3): 22-27.

• Special Topic • Previous Articles     Next Articles

100 Gbit/s Nyquist-WDM PDM 16-QAM Transmission over 1200 km SMF-28 with Ultrahigh Spectrum Efficiency

Ze Dong   

  1. ZTE USA, Morristown, NJ 07960, USA)
  • Received:2012-06-12 Online:2012-09-25 Published:2012-09-25
  • About author:Ze Dong (zdong9@mail.gatech.edu) received his BS degree in electronic information science and technology from Hunan Normal University, China, in 2006. He received his PhD degree in electrical engineering from Hunan University, Changsha, in 2011. From 2009 to 2011, he was a PhD exchange scholar at Georgia Institute of Technology, Atlanta. He is currently a postdoctoral fellow in the School of Electrical and Computer Engineering, Georgia Institute of Technology. His research areas are broadband optical communication and optical coherent ccommunications. He has authored or co-authored more than 40 papers and conference proceedings on coherent optical transmission, passive optical networks, and broadband radio-over-fiber systems.

Abstract: Nyquist wavelength-division multiplexing (N-WDM) allows high spectral efficiency (SE) in long-haul transmission systems. Compared to polarization-division multiplexing quadrature phase-shift keying (PDM-QPSK), multilevel modulation, such as PDM 16 quadrature-amplitude modulation (16-QAM), is much more sensitive to intrachannel noise and interchannel linear crosstalk caused by N-WDM. We experimentally generate and transmit a 6 × 128 Gbit/s N-WDM PDM 16-QAM signal over 1200 km single-mode fiber (SMF)-28 with amplification provided by an erbium-doped fiber amplifier (EDFA) only. The net SE is 7.47 bit/s/Hz, which to the best of our knowledge is the highest SE for a signal with a bit rate beyond 100 Gbit/s using the PDM 16-QAM. Such SE was achieved by DSP pre-equalization of transmitter-side impairments and DSP post-equalization of channel and receiver-side impairments. Nyquist-band can be used in pre-equalization to enhance the tolerance of PDM 16-QAM to aggressive spectral shaping. The bit-error ratio (BER) for each of the 6 channels is smaller than the forward error correction (FEC) limit of 3.8 × 10-3 after 1200 km SMF-28 transmission.

Key words: 16-QAM, coherent detection, Nyquist wavelength-division multiplexing, Nyquist-band, pre-equalization, spectral efficiency, signal transmission