title: Effect of second order signal-noise interactions in nonlinearity compensated optical transmission systems.
abstract: In this Letter, we theoretically and numerically analyze the performance of coherent optical transmission systems that deploy inline or transceiver based nonlinearity compensation techniques. For systems where signal-signal nonlinear interactions are fully compensated, we find that beyond the performance peak the signal-to-noise ratio degradation has a slope of 3 dBSNR/dBPower suggesting a quartic rather than quadratic dependence on signal power. This is directly related to the fact that signals in a given span will interact not only with linear amplified spontaneous emission noise, but also with the nonlinear four-wave mixing products generated from signal-noise interaction in previous (hitherto) uncompensated spans. The performance of optical systems employing different nonlinearity compensation schemes were numerically simulated and compared against analytical predictions, showing a good agreement within a 0.4 dB margin of error.
authors.forename: Mohammad A Z
authors.initials: MA
authors.lastname: Al-Khateeb
authors.forename: Mary
authors.initials: M
authors.lastname: McCarthy
authors.forename: Christian
authors.initials: C
authors.lastname: Sánchez
authors.forename: Andrew
authors.initials: A
authors.lastname: Ellis