Cisco Technology, Inc.

Gabriella Bosco

Fabrizio Forghieri

Pierluigi Poggiolini

Andrea Carena

Vittorio Curri

Theodor Kupfer

Chris Fludger

Monica Visintin

A method for transmitting a coherent optical data signal includes receiving a data signal from an interface, and encoding the data signal with a forward error correcting (FEC) encoder according to a mix of modulation formats. The FEC encoder generates an FEC encoded signal which is used to generate modulation symbols according to the modulation formats. The FEC encoded signal of modulation symbols is spectrally shaped to generate a shaped signal, and pre-distorted before transmission. The shaped signal is pre-distorted by adding a predetermined amount of chromatic dispersion to generate a smoothed signal, and the smoothed signal is transmitted according to the modulation formats.

Optimization of optical transmission capacity

A coherent optical receiver including an optical transducer, an adaptive filter, and a processor updates the adaptive filter according to a metric derived in Stokes space. The optical transducer receives an optical signal corresponding to a modulated signal of symbols. The optical transducer also determines a first signal corresponding to a first polarization of the optical signal and a second signal corresponding to a second polarization of the optical signal. The adaptive filter recovers a first equalized signal and a second equalized signal from the first signal and the second signal. The first equalized signal and the second equalized signal form an equalized modulated signal of symbols. The processor calculates a set of Stokes parameters from the equalized modulated signal and updates the adaptive filter based on a metric derived from the set of Stokes parameters.

Adaptive equalization in coherent receivers using a Stokes space update algorithm

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Bollengo, Italy

Gabriella Bosco