[BP] Signaling ad-hoc conference call minutes 16-9-04

Signaling ad-hoc: minutes (September 16, 2004)

Mike Altman begins with an agenda review from (http://ieee802.org/3/ap/public/signal_adhoc/altmann_02_0904.pdf)
Ali Ghiasi and Steve Anderson present the StatEye based proposal (http://ieee802.org/3/ap/public/signal_adhoc/ghiasi_01_0904.pdf ).
- Ali starts with an introduction to StatEye.
  - No Duobinary support is currently supported but Ali feels that it should not be a big deal to add it in.
  - A question was raised regarding S-parameters and ABC parameters? What are they?
    - Mike This is a translation step for matrix manipulations used for cascading s-parameters sets.
  - Mike Does StatEye allow mismatching of DC impedances ?
    - Ali Yes.
    - Mike And can these be changed independently?
      - Steve A. Not in the version I am familiar with.
      - Ali yes by modifying the script
- Steve continues the presentation
  - ISI
    - Fulvio What do you mean when you say that MSJ does not include ISI effects?
    - Steve I meant that MSJ was developed foe channels where there was not much attenuation.
  - ADS
    - Mike Is the ADS support definite?
    - John Yes, Agilent seems interested in doing so.
  - BER
    - Mike Does the BER include RJ?
    - Steve Yes
    - Mike Can you comment on how RJ is added? Is it just added to the contours extracted from impulse response?
    - Steve RJ is added by computing the composite PDF. Slides later in the presentation will discuss it.
  - CORRELATION
    - Mike Is there any data correlating StatEye to measured channels
    - Joe It is generally agreed that StatEye is conservative.
    - Ali That is always true when dealing with statistics vs. measurements.
    - Charles If we are using the tool for comparing signaling methods, the only important point is whether any pessimism may or may not be independent of signaling techniques.
    - ?? but there is still need for absolute performance indicators
    - Mike Yes, I would like to encourage an approach that shows correlation to measurements.
  - RJ
    - Mike It is not clear that the probability distribution (slide 21) includes random effects. It seems pretty deterministic. Am I interpreting correctly?
    - Steve Bit patterns randomize the results.
    - Mike But that is not really random
    - Steve Slide 21 illustrates the conditional probability function due to ISI.
    - ??? Are you sure that this does not include voltage noise.
    - Ali ... whatever shortcomings there may be we need a starting point ...
  - MULTILEVEL SUPPORT
    - Mike Things get even more complicated as we increase the number of levels. Have the StatEye folks validated other line codes.
    - Steve They have added PAM and RLL. The only thing missing is Duobinary.
    - Ali They have 8B10B, 64/66 etc.
    - Mike How do they include the effects of coding ? 8B10B and 64/66 are probably not the best for PAM4?
    - Ali It should not be difficult, given a certain encoding scheme. We could add a PAM4 encoder, modify one or ask them for modifications.
    - Adam Actually StatEye is based on random equi-probable bit sequences. For example, selecting 8B10B has the only consequence of changing the symbol rate. No other effect is included.
    - Ali You can always import a bit sequence appropriately encoded
  - S-Parameters
    - John I just want to verify that StatEye is only concerned about Sdd
    - Steve Yes, StatEye does not use CM to DIFF and vice versa.
    - Charles Hspice does, but in practice it depends on the information embedded in the Tx and Rx
  - ADAPTATION
    - Mike What kind of adaptation? MMSE? LMS?
    - Ali They (StatEye) so some global optimization
    - Steve Originally StatEye tried to determine the coefficients on a local basis but now it's looking at it globally scanning both coefficients and sampling point.
    - Mike So the optimization is not really representative of a particular algorithm or inclusive of any correlation/interaction between different loops. So it is, basically, a stationary process.
    - Fulvio what about the effects of coefficients quantization/granularity
    - Steve It was discussed some time ago but I do not know if it has been pursued.
  - MULTILEVEL
    - Mike Do you have an example of multilevel coding. It would be very good to see examples of how this is done. Are any of the multilevel guys in this group using StatEye? ...
    - Mike It sounds like that is not the case. Can I ask an experienced user to demonstrate StatEye on multilevel code?
    - John This should include Duobinary.
    - Mike Yes, absolutely. I am not going to care who does it as long as it gets done. I am asking for a volunteer. If none is found, we will have to find a volunteer some other way.
    - ? StatEye for PAM4 was demonstrated at OIF
    - Adam I am familiar with this presentation. What did not come out of it is the suitability of StatEye for PAM4 simulation. We need to have someone do so. We should do the same for Duobinary (or other signaling schemes that could be proposed in September, e.g. PR4)
    - Mike Soliciting volunteers ...
Mike thanks the presenters.
Mike resumes his presentation, illustrating the areas that need work:
- channel simulation model (slide 3)
- viability of ABC matrix cascading (slide 4)
- type of Data. Encoding. Typical packaging effects. (slide 5)
- BER or sensitivity of BER to input noise? Timing Recovery sensitivity. Interferers (slide 6)
Mike these are the topics I would like to have addressed so we can be clear on how to proceed. Anything else to add ..
- Fulvio Specify the number of aggressors
Mike ... anything else? No!
Mike (to Adam) Could we have specific ad-hoc signaling meetings in conjunction with the Interim mtg in Ottawa?
Adam I would hesitate to do so. But there are discretionary alternatives (evenings etc). I can talk to the meeting organizers.
Mike Fair enough. We will play it by ear.
Adam Since this is not a plenary, evenings are our own and we can certainly set up things for one night.
Adam We need to make sure to have presentations filed for the general meetings.
Meeting adjourned.