Driving Requirements for Wavelength Shifting in Colorless ONU With Dual-Arm Modulator

Abstract

Dual-arm modulator configurations to perform wavelength shifting at the optical network units (ONUs) for the mitigation of Rayleigh backscattering impairment in bidirectional centralized-light passive optical networks (PONs) are proposed, with different solutions compared. A 7 dB of sensitivity improvement due to the reduction in the Rayleigh scattering crosstalk between up- and down-stream signals is achieved with a suboptimal solution based on a conventional Mach-Zenhder modulator.