[BP] FW: Signaling ad-hoc conference call minutes 2-9-04
Dear 802.3ap Task Force members (Signalling ad
hoc),
Attached are the minutes from the 2 Sept'04
signaling ad hoc meeting. Thanks to Fulvio Spagna for taking the
minutes.
I have also included an updated attendance spread
sheet and attached it here. Please let me know if there any
errors.
.../Mike
- meeting called to
order
- Mike A. reviewed
the agenda (http://ieee802.org/3/ap/public/signal_adhoc/altmann_01_0904.pdf)
and the outline of the channel model to be used in simulation.
- discussion
follows regarding the methodology to be followed in converting
s-parameters data to time domain impulse response (windowing techniques,
etc.)
- discussion
continued on the suite of models that will be needed to
effectively simulate the channel. This allowed mike to introduce John
D'Ambrosia presentation.
- John
reviewed his presentation (http://ieee802.org/3/ap/public/signal_adhoc/dambrosia_01_0904.pdf)
- A typo was
detected in the description of the second configuration listed on slide 6.
The description should read: 6" line card > 20" backplane > 6" line
card
- Richard
questions whether the list includes resonant cases
- As slide 7 is
reviewed, the list of proposed data is presented. Case 1,2,3 focus on long
channels while the other cases focus on medium and short interconnect. All
data is focused on ATCA pinouts (tx, rx are interleaved as per ATCA
spec).
- Tyco is willing
to make the data available to non-competitors members under NDA. Tyco is
willing to let members share simulation results based on that data. Tyco
will make a reference presentation of raw data which should be used in
reporting results in light of presenting raw data.
- discussion
follows:
- J. Abler
suggests that John writes the terms of the NDA
- John
D'Ambrosia agreed to do so
- J.
Abler indicates that the proviso
of sharing data to "non-competitors" is too restrictive and not
inline with IEEE guidelines.
- Adam
indicates that the issue is not quite clear and he will try
to consult with Bob Grove
-
Justin states that it's necessary to get out of the mode
of treating other parties as competitors
- As the
discussion continued, Joel made the point that the idea of accepting
the definition of an improved FR4 based on dk, df is to create
a template that all can accept. In particular this should
give other manufacturers the capability of duplicate John's work as
long as they stick to the accepted definition of FR4 and best design
practice.
- At this
point Mike A. tried to poll the participants to find out if there was
agreement that the suite of cases was comprehensive (necessary and
sufficient).
- Charles
commented that he needed to look at the raw data before being able to
pass a judgment
- Richard
commented that impedance variations may not have been included
...
- ... and
John moved on to the last slide which listed other considerations that
will affect channel characteristics
- Once again, Mike
tried to get the group to comment on whether the configuration listed in
John's presentation were comprehensive
- lots of
concerns were stated regarding particular issues
- As a result of the
discussion, John requested that the signaling ad hoc would state the
number of simulations deemed feasible to characterize a certain
design/solution
- A straw poll
asked for objections to Johns presented list of channels being used as a
starting point
- A straw
poll asked the group to comment on
whether they thought more or less than 20 sims were required
- less than 20:
17 votes
- greater than
20: 2 votes
- abstained: 3
votes
- John Stonick
walked through his presentation (http://ieee802.org/3/ap/public/signal_adhoc/stonick_01_0904.pdf).
- John indicates
that s-parameters data can be remapped to emulate short/long
channels
- Brian
expresses the concern that this can cause unrealizable
channels
- John agreed indicating that the technique should be used more as a
perturbation
- John presented
a statistical approach to simulating crosstalk
- John will
clarify how this works
- Meeting ended
with the agreement to schedule an out of program conference call for next
Thursday (9 Sept'04) to keep the work going. Also the participants are encouraged to
continue the discussion on the
reflector.
- Meeting
closd
signaling_adhoc_attendance_master_list.xls