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[STDS-802-3-400G] Follow up to IEEE P802.3bs 400 Gb/s Ethernet SMF Ad Hoc conference call



Dear all,

 

During yesterday’s SMF ad hoc conference call I presented http://www.ieee802.org/3/bs/public/adhoc/smf/14_09_30/stassar_01_0914_smf.pdf.

 

This presentation contained some questions to all for follow-up.

The most important were:

         Identify a working assumption for reasonable transmitter output power: in my presentation I mentioned -1.5dBm as a realistically minimum average transmitter output power before the mux, but comments were made that this value is too low. The value of -1.5dBm however was intended for a TDP value of 1 dB. In the case of a TDP of 3 dB that minimum value could go up to +0.5 dBm, at least in the case of the power budget example contained in my presentation. So I would appreciate inputs on not only a realistic minimum value, but also a realistic range (thus upper value).

         Can we sufficiently minimize ISI with PAM4 transmitters or will it require exotic technology? This question is intended to jointly investigate the source of the (potential) BER-floor seen in most experiments with PAM4. I believe addressing this question will be essential if we would like to use the PAM4 modulation format. For these experiments I suggested to use SSPR patterns instead of the shorter PRBS15 patterns. Of course PRBS31 will be OK as well.

 

Additional questions, related to the previous issue:

         Related to the BER-floor question, we may want to investigate this issue while varying the bitrate, perhaps even for 10Gb/s, 25Gb/s, 50Gb/s and 100Gb/s.

         During the experiments it will be very useful which parameters will move the BER floor up and down.

         Furthermore I suggest to add Tx eye diagrams to all inputs and investigate the effect of jitter to this.

 

Finally I would appreciate any further questions, comments and/or suggestions to my presentation.

 

Thanks in advance.

I am looking forward to continue our constructive debate during the next SMF ad hoc call on Tuesday 14 October.

 

Kind regards,

 

Peter

 

Peter Stassar, 施笪安

Technical Director, 术总监

Huawei Technologies Ltd, 华为技术有限公司

European Research Center, 欧洲研究所

Karspeldreef 4, 1101CJ Amsterdam

The Netherlands

Tel: +31 20 4300 832

Mob: +31 6 21146286