64-Tb/s, 8 b/s/Hz, PDM-36QAM Transmission Over 320 km Using Both Pre- and Post-Transmission Digital Signal Processing

We report the successful transmission of 64 Tb/s capacity (640 ×107 Gb/s with 12.5 GHz channel spacing) over 320 km reach utilizing 8-THz of spectrum in the C+L -bands at a net spectral efficiency of 8 bit/s/Hz. Such a result is accomplished by the use of raised-cosine pulse-shaped PDM-36QAM modulation, intradyne detection, both pre- and post-transmission digital equalization, and ultra-large-area fiber. We discuss in detail the digital modulation technology and signal processing algorithms used in the experiment, including a new two-stage, blind frequency-search-based frequency-offset estimation algorithm and a more computationally efficient carrier-phase recovery algorithm.

[1]  Ting Wang,et al.  64-Tb/s (640×107-Gb/s) PDM-36QAM transmission over 320km using both pre- and post-transmission digital equalization , 2010, 2010 Conference on Optical Fiber Communication (OFC/NFOEC), collocated National Fiber Optic Engineers Conference.

[2]  Ting Wang,et al.  17 Tb/s (161×114 Gb/s) PolMux-RZ-8PSK transmission over 662 km of ultra-low loss fiber using C-band EDFA amplification and digital coherent detection , 2008, 2008 34th European Conference on Optical Communication.

[3]  J. Yu,et al.  Cascaded two-modulus algorithm for blind polarization de-multiplexing of 114-Gb/s PDM-8-QAM optical signals , 2009, 2009 Conference on Optical Fiber Communication - incudes post deadline papers.

[4]  Xiang Zhou,et al.  Multi-Level, Multi-Dimensional Coding for High-Speed and High-Spectral-Efficiency Optical Transmission , 2009, Journal of Lightwave Technology.

[5]  N. S. Bergano,et al.  Transmission of 96×100G pre-filtered PDM-RZ-QPSK channels with 300% spectral efficiency over 10,608km and 400% spectral efficiency over 4,368km , 2010, 2010 Conference on Optical Fiber Communication (OFC/NFOEC), collocated National Fiber Optic Engineers Conference.

[6]  A. Al Amin,et al.  132.2-Gb/s PDM-8QAM-OFDM Transmission at 4-b/s/Hz Spectral Efficiency , 2009, IEEE Photonics Technology Letters.

[7]  Xiang Zhou,et al.  An Improved Feed-Forward Carrier Recovery Algorithm for Coherent Receivers With $M$ -QAM Modulation Format , 2010, IEEE Photonics Technology Letters.

[8]  A. Al Amin,et al.  8×66.8-Gbit/s coherent PDM-OFDM transmission over 640 km of SSMF at 5.6-bit/s/Hz spectral efficiency , 2008, 2008 34th European Conference on Optical Communication.

[9]  A. Sano,et al.  100 × 120-Gb/s PDM 64-QAM transmission over 160 km using linewidth-tolerant pilotless digital coherent detection , 2010, 36th European Conference and Exhibition on Optical Communication.

[10]  M. Seimetz.  Laser Linewidth Limitations for Optical Systems with High-Order Modulation Employing Feed Forward Digital Carrier Phase Estimation , 2008, OFC/NFOEC 2008 - 2008 Conference on Optical Fiber Communication/National Fiber Optic Engineers Conference.

[11]  J. Kahn,et al.  Feedforward Carrier Recovery for Coherent Optical Communications , 2007, Journal of Lightwave Technology.

[12]  Ting Wang,et al.  Transmission of 32-Tb/s Capacity Over 580 km Using RZ-Shaped PDM-8QAM Modulation Format and Cascaded Multimodulus Blind Equalization Algorithm , 2010, Journal of Lightwave Technology.

[13]  T. Kobayashi,et al.  69.1-Tb/s (432 × 171-Gb/s) C- and extended L-band transmission over 240 km Using PDM-16-QAM modulation and digital coherent detection , 2010, 2010 Conference on Optical Fiber Communication (OFC/NFOEC), collocated National Fiber Optic Engineers Conference.

[14]  Ting Wang,et al.  112.8-Gb/s PM-RZ-64QAM optical signal generation and transmission on a 12.5GHz WDM grid , 2010, 2010 Conference on Optical Fiber Communication (OFC/NFOEC), collocated National Fiber Optic Engineers Conference.

[15]  Itsuro Morita,et al.  DWDM transmission with 7.0-bit/s/Hz spectral efficiency using 8×65.1-Gbit/s coherent PDM-OFDM signals , 2009, 2009 Conference on Optical Fiber Communication - incudes post deadline papers.

[16]  M. Magarini,et al.  Spectrally Efficient Long-Haul Optical Networking Using 112-Gb/s Polarization-Multiplexed 16-QAM , 2010, Journal of Lightwave Technology.

[17]  I. Fatadin,et al.  Compensation of Frequency Offset for Differentially Encoded 16- and 64-QAM in the Presence of Laser Phase Noise , 2010, IEEE Photonics Technology Letters.

[18]  R. Noe,et al.  Hardware-Efficient Coherent Digital Receiver Concept With Feedforward Carrier Recovery for $M$ -QAM Constellations , 2009, Journal of Lightwave Technology.