Nonlinear compensation technologies for future optical communication systems

Digital nonlinear compensation techniques have been thought to be keys to realize further spectrally efficient optical fiber communication systems. The most critical issue of the digital nonlinear compensation algorithms has been their computational complexity, or gate count of digital signal processing circuit. Among several approaches, digital nonlinear compensation algorithms based on perturbation analysis are attractive in terms of the hardware efficiency because the algorithms can compensate the accumulated nonlinear noise over all transmission spans with only one stage. In this paper, we discuss three approaches to sophisticate the perturbation nonlinear compensation. First, we illustrate a perturbation-based post-equalization method to improve the robustness to transceiver device imperfections. We next propose and numerically evaluate a symbol degeneration method to extend the perturbation nonlinear compensation methods to higher-order QAM without increasing the computational complexity. Finally, we discuss a sub-band processing of perturbation nonlinear compensation for further computational complexity reduction. By combining the perturbation method with Nyquist frequency division multiplexing, the computational complexity of perturbation calculation is reduced by a factor of more than 10 for 3000-km single-channel transmission of 128 Gbit/s dualpolarization QPSK with only 0.1 dB performance degradation.

[1]  Yuichi Akiyama,et al.  Real-time 112Gb/s DWDM coherent transmission with 40% extended reach by transmitter-side low-complexity nonlinear mitigation , 2012, 2012 38th European Conference and Exhibition on Optical Communications.

[2]  S. Chandrasekhar,et al.  Multiband DFT-spread-OFDM equalizer with overlapand-add dispersion compensation for low-overhead and low-complexity channel equalization , 2013, 2013 Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC).

[3]  Ting Wang,et al.  Complexity versus performance tradeoff for fiber nonlinearity compensation using frequency-shaped, multi-subband backpropagation , 2011, 2011 Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference.

[4]  Yuichi Akiyama,et al.  PMD and PDL tolerances of transmitter-side non-linear mitigation in 112 Gb/s DP-QPSK transmission , 2012, 2012 38th European Conference and Exhibition on Optical Communications.

[5]  Takeshi Hoshida,et al.  Low complexity digital perturbation back-propagation , 2011, 2011 37th European Conference and Exhibition on Optical Communication.

[6]  Wei-Ren Peng,et al.  Extending perturbative nonlinearity mitigation to PDM-16QAM , 2014, 2014 The European Conference on Optical Communication (ECOC).

[7]  David V. Plant,et al.  Aggressive quantization on perturbation coefficients for nonlinear pre-distortion , 2014, OFC 2014.

[8]  Moshe Nazarathy,et al.  Subbanded DSP Architectures Based on Underdecimated Filter Banks for Coherent OFDM Receivers: Overview and recent advances , 2014, IEEE Signal Processing Magazine.

[9]  William Shieh,et al.  Ultrahigh-Speed Signal Transmission Over Nonlinear and Dispersive Fiber Optic Channel: The Multicarrier Advantage , 2010, IEEE Photonics Journal.

[10]  J. Kahn,et al.  Compensation of Dispersion and Nonlinear Impairments Using Digital Backpropagation , 2008, Journal of Lightwave Technology.

[11]  Yuichi Akiyama,et al.  Complexity reduction of perturbation-based nonlinear compensator by sub-band processing , 2015, 2015 Optical Fiber Communications Conference and Exhibition (OFC).

[12]  Takeshi Hoshida,et al.  Proposal of improved 16QAM symbol degeneration method for simplified perturbation-based nonlinear equalizer , 2014, 2014 OptoElectronics and Communication Conference and Australian Conference on Optical Fibre Technology.

[13]  Zhenning Tao,et al.  Multiplier-Free Intrachannel Nonlinearity Compensating Algorithm Operating at Symbol Rate , 2011, Journal of Lightwave Technology.

[14]  Takeshi Hoshida,et al.  Complexity reduction of perturbation pre-distortion by term combination , 2013, 2013 18th OptoElectronics and Communications Conference held jointly with 2013 International Conference on Photonics in Switching (OECC/PS).

[15]  Maurice O'Sullivan,et al.  Reducing the complexity of perturbation based nonlinearity pre-compensation using symmetric EDC and pulse shaping. , 2014, Optics express.

[16]  Zhihong Li,et al.  Optimum quantization of perturbation coefficients for perturbative fiber nonlinearity mitigation , 2014, 2014 The European Conference on Optical Communication (ECOC).

[17]  Alan Pak Tao Lau,et al.  Coherent detection in optical fiber systems. , 2008, Optics express.

[18]  Yan Cui,et al.  1.2 Tb/s Superchannel Transmission Over 80 $\,\times\,$100 km ULAF Using Nyquist FDM DP-QPSK , 2014, IEEE Photonics Technology Letters.

[19]  Arthur James Lowery,et al.  Optimizing the subcarrier granularity of coherent optical communications systems. , 2011, Optics express.

[20]  Takeshi Hoshida,et al.  Robust and efficient receiver-side compensation method for intra-channel nonlinear effects , 2014, OFC 2014.

[21]  Takeshi Hoshida,et al.  Impact of pulse shaping and transceiver electrical bandwidths on nonlinear compensated transmission , 2013, 2013 Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC).

[22]  F. Hauske,et al.  Intrachannel Nonlinearity Compensation by Inverse Volterra Series Transfer Function , 2012, Journal of Lightwave Technology.

[23]  J. C. Rasmussen,et al.  Pre-distortion method for intra-channel nonlinearity compensation with phase-rotated perturbation term , 2012, OFC/NFOEC.

[24]  Qunbi Zhuge,et al.  Digital subcarrier multiplexing for fiber nonlinearity mitigation in coherent optical communication systems. , 2014, Optics express.

[25]  Takeshi Hoshida,et al.  Efficient Transmitter-side Nonlinear Equalizer for 16QAM , 2013 .