Spectrally Efficient Quadrature Duobinary Coherent Systems With Symbol-Rate Digital Signal Processing

  title={Spectrally Efficient Quadrature Duobinary Coherent Systems With Symbol-Rate Digital Signal Processing},
  author={Jianqiang Li and Zhenning Tao and Huijian Zhang and Weizhen Yan and Takeshi Hoshida and Jens C. Rasmussen},
  journal={Journal of Lightwave Technology},
An enhanced digital coherent receiver including a novel blind equalization approach and maximum-likelihood sequence detection (MLSD) is proposed for dual-polarization quadrature duobinary (DP-QDB) systems. In virtue of the compact spectrum of DP-QDB signals approaching Nyquist limit, the equalization is implemented at symbol rate, which relaxes the demand on the sampling speed of analog-to-digital converters (ADCs). The proposed symbol-rate receiver is verified by 43 Gb/s experiments in the… 
Multi-Modulus Blind Equalizations for Coherent Quadrature Duobinary Spectrum Shaped PM-QPSK Digital Signal Processing
A novel digital signal processing (DSP) scheme for quadrature duobinary (QDB) spectrum shaped polarization multiplexed quadrature phase shift keying (PM-QPSK) based on multi-modulus blind
Training Symbol-Based Equalization for Quadrature Duobinary PDM-FTN Systems
Comparisons with the Tomlinson–Harashima precoding-based FTN systems illustrate that QDB is preferable when 4-QAM is utilized, and an excellent convergence performance is obtained using the proposed algorithm under different polarization alignment scenarios.
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The transmission of 3-channel 112-Gbit/s PDM-QPSK signals at a 20-GHz channel spacing is demonstrated, which is detected as a quadratures four-level polybinary signal, with performance comparable to PDM 16-ary quadrature-amplitude modulation (16QAM) at the same bit rate.
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We discuss the generation, wavelength-division-multiplexed (WDM) long-haul transmission, and coherent detection of 112-Gb/s polarization-division-multiplexed (PDM) 16-ary quadrature amplitude
Transmission of 32-Tb/s Capacity Over 580 km Using RZ-Shaped PDM-8QAM Modulation Format and Cascaded Multimodulus Blind Equalization Algorithm
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Compensation of Quadrature Imbalance in an Optical QPSK Coherent Receiver
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Digital filters for coherent optical receivers.
Using the analytical solution an upper bound on the number of taps required to compensate chromatic dispersion is obtained, with simulation revealing an improved bound of 2.2 taps per 1000ps/nm for 10.7GBaud data.
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Adaptive equalization
  • S. Qureshi
  • Computer Science
    Proceedings of the IEEE
  • 1985
This tutorial paper gives an overview of the current state of the art in adaptive equalization and discusses the convergence and steady-state properties of least mean-square (LMS) adaptation algorithms, including digital precision considerations, and three classes of rapidly converging adaptive equalizer algorithms.
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We investigate, by means of simulations, polarization-multiplexed (PolMux) quadrature duobinary (QDB) as a modulation format for transmitting 111-Gb/s signals with high spectral efficiency (SE) and
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A shell partition-based CMA (SPCMA), a multi-modulus CMA based on the equalizer output power, in which decision boundaries are obtained by maximum likelihood (ML) estimation is proposed, showing the optimum performance for QAM constellations.