MODULATOR FOR OPTICAL TRANSMITTER

摘要

An optical transmitter has a modulator for modulating data onto an optical signal for transmission to the receiver, the modulated signal having components at one or more constellations of points of different amplitudes and phases. The modulator is tunable such that distortions of the points of the one or more constellation can be tuned, and a tuning controller is provided for receiving a feedback signal from the receiver indicating a distortion measured at the receiver, and for tuning automatically the modulator to adjust the modulation based on the received feedback signal to pre-compensate for the measured distortion. Such pre-compensation can reduce the amount of distortion in the transmission system and thus enable more transmission capacity, without the need for a complex transmitter.

主权项

1. An optical transmitter for an optical communications system having a remote optical coherent receiver, the optical transmitter comprising:
a modulator, configured to modulate data onto an optical signal for transmission to the coherent receiver, the modulated signal having components at one or more constellations of points of different amplitudes and phases, the modulator being tunable such that distortions of the one or more constellations can be tuned; and a tuning controller configured to:
receive a feedback signal from the coherent receiver indicating a distortion measured at the coherent receiver, andautomatically tune the modulator to adjust a modulation based on the received feedback signal to pre-compensate for a measured distortion.