Generation of 1024-Tb/s Nyquist-WDM phase-conjugated twin vector waves by a polarization-insensitive optical parametric amplifier for fiber-nonlinearity-tolerant transmission

Xiang Liu,M Dinu,A H Gnauck,Hao Hu,S Chandrasekhar,P J Winzer,C Xie,R M Jopson

doi:10.1364/oe.22.006478

Abstract

We experimentally demonstrate the generation of 1.024-Tb/s Nyquist-WDM phase-conjugated vector twin waves (PCTWs), consisting of eight 128-Gb/s polarization-division-multiplexed QPSK signals and their idlers, by a broadband polarization-insensitive fiber optic parametric amplifier. This novel all-optical signal processing approach to generate WDM-PCTWs enables a 2-fold reduction in the needed optical transmitters as compared to the conventional approach where each idler is generated by a dedicated transmitter. Digital coherent superposition of the twin waves at the receiver enables more than doubled reach in a dispersion-managed transmission link. We further study the impact of polarization-mode dispersion on the performance gain brought by the phase-conjugated twin waves, showing a gain of ~3.8 dB in signal quality factors.

Highlights

Fiber nonlinearity imposes major impairments that limit the achievable transmission distance of optical communication systems [1,2]
We experimentally demonstrate the generation of 1.024-Tb/s Nyquist-WDM phase-conjugated vector twin waves (PCTWs), consisting of eight 128-Gb/s polarization-division-multiplexed QPSK signals and their idlers, by a broadband polarization-insensitive fiber optic parametric amplifier
This novel all-optical signal processing approach to generate WDM-PCTWs enables a 2-fold reduction in the needed optical transmitters as compared to the conventional approach where each idler is generated by a dedicated transmitter

Summary

Introduction

Fiber nonlinearity imposes major impairments that limit the achievable transmission distance of optical communication systems [1,2]. To further mitigate inter-channel nonlinear impairments, it was suggested to form wavelength-division-multiplexed (WDM) PCTWs where one polarization of the entire WDM spectrum is the phase-conjugated and spectrallyinverted copy of the other polarization [8,10]. To generate such broadband WDM-PCTWs, fiber optic parametric amplifiers (OPAs) [11,12] are well suited. We present this study in more depth, and investigate the impact of polarization-mode dispersion (PMD) on the performance gain of the DCS of the PCTWs, showing the benefit of the DCS in improving the worst-case signal qualities and in tightening the performance distribution

Generation of WDM-PCTWs

Experimental setup and back-to-back performance

Impact of PMD

Conclusions