Raman Crosstalk Suppression in CATV Overlay Passive Optical Network

Overview

In CAble TeleVision (CATV) overlay Passive Optical Networks (PONs), where a CATV signal copropagates with a downstream baseband signal, the crosstalk components mediated by Stimulated Raman Scattering (SRS) limit the performance of low-number CATV channels. This paper proposes and demonstrates a way of reducing the SRS-induced crosstalk in CATV overlay PONs. The proposed scheme utilizes a high-speed polarization scrambler in the transmitter to make the SRS-induced crosstalk independent of polarization evolution along the fiber and a subtractor module to compensate for the crosstalk. The demonstration shows that crosstalk can be reduced by 9 dB.