Compensation of linear and nonlinear signal distortion by optimized digital backward propagation

Chien Yu Lin, Rameez Asif, Michael Holtmannspoetter, Bernhard Schmauss

Research output: Chapter in Book/Report/Conference proceedingConference contribution


We present results of nonlinear compensation achieved by digital backward-propagation (DBP) for next-generation optical coherent transmission systems. In our numerical investigations, phase-encoded signals (DQPSK) as well as signals of higher-order modulation formats (16-QAM) have been analyzed with respect to degradation by fiber nonlinearity such as self-phase modulation (SPM). The influence of inline compensation schemes used is studied and we also showed that DBP performance depends strongly on its parameters. A careful adjustment of e.g. the nonlinear calculating position improves the eye opening up to 3.5dB for DQPSK signals. Our work also includes investigations on optimized step-size selection. The implementation of a logarithmic step-size distribution reduces the numerical effort by about 50% with respect to using constant step-size distributions in 112Gbps 16-QAM transmission. Furthermore, by using an additional low-pass-filter (LPF) in each DBP stage, the required number of DBP stages is significantly reduced, where the computational efficiency can be enhanced without significant loss of performance, which will be helpful in future deployment of DBP in real-time signal processing modules for non-linear compensation. In order to explore the capability of this filtered DBP in terms of complexity, the results of diverse baud rates for multiple channel DP-QPSK systems with a total transmission capacity of 1.12 Tbit/s are compared.

Original languageEnglish
Title of host publicationPhotonische Netze - 13. ITG-Fachtagung
PublisherVDE Verlag GmbH
Number of pages6
ISBN (Electronic)9783800734375
Publication statusPublished - 2020
Event13. ITG-Fachtagung Photonische Netze - 13th ITG Conference on Photonic Networks - Leipzig, Germany
Duration: 7 May 20128 May 2012

Publication series

NamePhotonische Netze - 13. ITG-Fachtagung


Conference13. ITG-Fachtagung Photonische Netze - 13th ITG Conference on Photonic Networks

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