Intra super-channel fiber nonlinearity compensation in flex-grid optical networks

Abstract

Abstract:We report on the nonlinear transmission limits of various superchannel configurations in a flex-grid network upgrade scenario. In particular, we consider flexible data-rates ranging from 180Gb/s to 1.2Tb/s, employing either single-carrier, dual-carrier, or penta-carrier polarization multiplexed m-state quadrature amplitude modulation (PM-8QAM/PM-16QAM) -termed as super-channels, and establish transmission performance margins for each configuration, both with and without superchannel fiber nonlinearity compensation. Our results show that the benefit of intra super-channel nonlinearity mitigation (nonlinear compensation addressing full super-channel bandwidth) reduces with increasing subcarrier count within the super-channel, and that single-carrier super-channel achieves the maximum improvement from nonlinearity mitigation (up to ~4.5dB, in Q-factor), better than dual-carrier (up to ~3.5dB) and pentacarrier (up to ~2dB) configurations. Moreover, the maximum reach improvement, compared to linear compensation only, is found to be ~170%

Fiber Nonlinearity Compensation: Commercial Applications and Complexity Analysis

“…With mass rollouts of 100Gb/s QPSK products, and 200Gb/s PM-16QAM in pipeline, next-generation super-channel based transponders are under discussion [66][67][68][69]. In this section we explore intra super-channel NLC (NLC bandwidth equals super-channel bandwidth) gains for single-carrier 200Gb/s 16QAM, dual-carrier 400Gb/s 16QAM and pent-carrier 1Tb/s 16QAM super-channels.…”

Intra super-channel nonlinearity mitigation in uniform and non-uniform links employing pre-dispersed spectral inversion

“…In order to minimize linear crosstalk, sub-carrier spacing was fixed at ∼1.15 × baud-rate [6], and digital spectral shaping was employed using a filter roll off of 0.2. In order to emulate a network upgrade scenario, the neighboring channels (×12) were considered to be 120Gb/s PM-QPSK (spaced at 50GHz), and the launch power of neighboring traffic was fixed at 0dBm [5].…”

“…In this context, the nonlinear performance impact of fibertype mix was investigated in [3], [4]. Recently, pre-dispersed spectral inversion based fiber nonlinearity mitigation has been shown to have substantial benefits [5], thus it is also critical to quantify the impact of non-uniform fiber links on the performance of fiber nonlinearity mitigation.…”

The impact of spectral inversion placement for nonlinear phase noise mitigation in non-uniform transmission links

“…Recently super-channel transmission with higher order modulation formats has received attention for higher data rate transport in next generation optical networks to achieve better spectral efficiency [1]. The higher order modulation formats can improve spectral efficiency at the expense of the optical reach due to higher OSNR requirement.…”