96G/192GBaud with PDM-32QAM and 120G/240GBaud with PDM-16QAM listed for 800G

OTT Service Provider Considers 800G Coherent

800G (and 1.6T) Ethernet talks are coming to a close. Four meetings were scheduled for September, one of which was canceled and three meetings were held.

　The September meeting was basically an update of the Project Document, including PAR and CSD, and the content was an extension of the story explained so far. In other words, first of all, the consideration of Document is progressing smoothly.

　Among all that, the only new story was the presentation "Feasibility study of coherent 800Gb/s for 10km & 40km" by Mr. Huijian Zhang of HiSilicon Optoelectronics. According to this, the OTT service provider seems to be very interested in 800G Coherent, and they are considering it.

The problem is that the document shown here cannot be downloaded from the publication site here, and the contents cannot be confirmed. Apparently you can't get it unless you become a member of IPEC

Now, below is the relationship between signal speed and SNR. Green is the Shannon limit (theoretical maximum channel capacity) at 800 Gbps, blue is 1.6 Tbps, and red is the upper limit of available SNR. Therefore, the area between the red and green or red and blue curves is the range of signal speed and SNR that can be used as a practical problem.

Since the vertical axis is "SNR required for communication", the worse the BER, the higher the required SNR

　Promising signal candidates within this range are 96G/192GBaud with PDM-32QAM or PDM-16QAM 120G/240GBaud was listed.