Capacity of a nonlinear optical channel with finite memory

E. Agrell, A. Alvarado, G. Durisi, M. Karlsson

Research output: Contribution to journalArticleAcademicpeer-review

91 Citations (Scopus)
3 Downloads (Pure)


The channel capacity of a nonlinear, dispersive fiber-optic link is revisited. To this end, the popular Gaussian noise (GN) model is extended with a parameter to account for the finite memory of realistic fiber channels. This finite-memory model is harder to analyze mathematically but, in contrast to previous models, it is valid also for nonstationary or heavy-tailed input signals. For uncoded transmission and standard modulation formats, the new model gives the same results as the regular GN model when the memory of the channel is about 10 symbols or more. These results confirm previous results that the GN model is accurate for uncoded transmission. However, when coding is considered, the results obtained using the finite-memory model are very different from those obtained by previous models, even when the channel memory is large. In particular, the peaky behavior of the channel capacity, which has been reported for numerous nonlinear channel models, appears to be an artifact of applying models derived for independent input in a coded (i.e., dependent) scenario.
Original languageEnglish
Pages (from-to)2862-2876
Number of pages15
JournalJournal of Lightwave Technology
Issue number16
Publication statusPublished - 15 Aug 2014


  • Channel capacity
  • Gaussian noise model
  • channelmodel
  • fiber-optic communications
  • nonlinear distortion


Dive into the research topics of 'Capacity of a nonlinear optical channel with finite memory'. Together they form a unique fingerprint.

Cite this