Dual-carrier-paired Point-to-multipoint Transmission over ROADM Systems: Frequency-polarization Coding and Frequency Collaborative Control

In dual-carrier (DC)-paired fiber optic long-reach transmission, which extends a point-to-multipoint coherent system to cascaded reconfigurable optical add-drop multiplexing (ROADM) system, narrow passband causes severe performance degradation of the edge subcarriers. this study, we proposed two-dimensional frequency and polarization domain coding multicarrier-frequency control for ROADM filtering robust multicarrier transmissions at single wavelength. The scheme reduced nonlinearity, polarization-dependent loss (PDL), narrowing (PBN) simultaneously. algorithm, feeds back received signal quality multiple points, PBN owing long-term laser drifts. With coding, Q value 56 Gbit/s × DC-paired dual-polarized (DP)-4QAM 112 DP-16QAM signals improved by 1 dB 0.2 dB, respectively, compared that when no was used. Furthermore, emulated through emulation model drifts average were less than 0.4 0.1 respectively. To best our knowledge, other study has evaluated transmission over ROADM-induced systems apply DP-M-QAM signals. methods enable stable operation while suppressing effects PDL PBN, are problems in integrate access metro networks.