Numerical study on wavelength-division multiplexing transmission of direct-detected amplitude and differential phase-shift keying-modulated signals using digital back-propagation

Abstract

This report is a detailed study on the application of digital back-propagation technique for wavelength-division multiplexing (WDM) transmission of amplitude and differential phase shift keying (ADPSK)-modulated signal. We find that the precompensation using digital back-propagation increases the transmission distance by more than a factor of two. We find that the performance improvement from digital precompensation strongly depends on the dispersion map of the transmission link and the optimum performance was obtained when about 3% to 5% of the span dispersion is under-compensated by in-line dispersion compensators and later compensated for at the end of the entire transmission link. We also find that the precompensation is robust enough to the variation of various link parameters which can occur in the deployment or operation of transmission systems.