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by electroagenda 1341 days ago
Congrats!

What modulation, bitrate and spectral efficiency did you use per WDM channel?

Was that rate achieved in real-time or with massive post processing?

1 comments

We used constellation shaping and a rate adaptive code to tailor tailor the bitrate of each channel. It varied between something along 64-QAM and 256-QAM depending on the SNR in the channel.

Post processing times were not too bad. It ran on a standard desktop computer and gave an estimate of the data rate in about a minute (can’t remember exactly). Of course, compared to actual transmission that is terrible slow, but that was only due to the implementation and need of this experiment.