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Regarding todays meeting:
EDC coefficients are obtained using MMSE and yes see
the hanberg_1_0304 presentation for BER calculation.
We are able to simulated lasers with peaking and ringing by
changing the gain compression factor. Attached is a figure
showing one of the lasers with a
lower gain compression coefficient (eps_nl =2.22e-007). Any views on how
realistic this looks?
The fiber used is ranked as the 22nd worst with regards to
PIE_L..
Best regards,
Jesper Hanberg
direct: +45 44 54 61
30
All -
Meeting details (same numbers as before):
-
Date: Thurs, 8/26/04 (regular day/time)
-
Time: 9:00 AM
-
Duration: 1:00 goal, 1:30 max
-
Number: 401-694-1515
-
Access code: 421721#
Topics
-
Approve agenda
-
Approve previous minutes (see below)
-
Questions for Intel (from 8/19 presentation)
- How were EDC coefficients were determined and how was BER calculated
(see hanberg_1_0304.pdf)?
- Where does fiber used line up in the Cambridge set? What cumulative
percentage does it represent of the installed base?
- Why are some results in slide 13 better than ideal PIE-D?
- New presentations/results?
-
Cost trends
- Penalties (relative to -L) and test metrics vs. TP2 parameters (try to
relate to cost trends)
- Lasers with overshoot and ringing
- More realistic electrical drive modeling to include reflections
- RIN
- Other tap combinations for FFE and DFE
-
Other?
TP2 test metrics (specs and
methods)
----- Original Message -----
Sent: Thursday, August 19, 2004 4:30
PM
Subject: [10GMMF] Notes for TP2 call,
8/19/04
All - here are my notes for the 8/19 TP2 call. Please send corrections if
needed.
Attendees (no order)
- Martin Lobel, Intel
- Jan Peeters Weem, Intel
- Sudeep Bhoja, Big Bear
- Bob Zona, Intel
- Jens Fielder, Infineon
- Lew Aronson, Finisar
- John Ewen, JDSU
- Yu Sun, Optium
- John Dallesasse, Emcore
- John George, OFS
- Bala Mayampurath, Vitesse
- Pekko Sipila, Modulight
- Abhijit Shanbhag, Scintera
- Piers Dawe, Agilent
- Tom Lindsay, ClariPhy
- Norm Swenson, ClariPhy
- Paul Voois, ClariPhy
- Chet Babla, PhyWorks
- Sudeep Bhoja, Big Bear
- Lars Thon; Aeluros
- I apologize for missing others who did not respond to my requests to
send emails.
Summary objective (repeated from before)
Present a proposal for TP2 signaling parameters and associated
conformance testing at the September Meeting. The work must consider and
provide tradeoff information among component cost, test cost, and power
penalties.
Reduction in power was mentioned by Lew today as another outcome to
consider.
Housekeeping
- Proposed agenda was approved (see below).
- Previous notes were approved.
Progress, technical discussions
Intel presentation (presented by Martin)
- Simulations.
- Considered penalties vs. laser packaging and laser chip performance.
- Note - laser driver is another variable...
- Packaging model was simple 4th-order Bessel Thomson (BT4) filter.
Reflections not considered.
- Laser chip modeling based on rate equations.
- Parameters chosen to result in various RO
frequencies.
- Other setup for this presentation.
- Single Cambridge fiber. Intel sampled a few fibers and found similar
trends. 300 meter (no scaling).
- Rx front-end BT4 filter @ 7.5 GHz.
- Equalizer taps at T/2 spacing.
- FFE 5 taps.
- Feedback taps (for DFE): 2.
- Reference penalty for all slides is lower right cell on slide 8
(perfect/perfect).
- RIN not included in this setup.
- Discussion
- Laser currents seem higher than normal.
- Observed that unfiltered eyes did not show classic overshoot and
ringing, that they were highly damped.
- Martin thoughts that trends would be the same, however.
- RIN should be included in future modeling. As eyes close, effect of
RIN increases.
- Curious why some results of slide 13 are better than PIE-D.
- FFE results on slide 15 seem pessimistic. May be due to small number
of taps (only 2.5 bits), but some tap limit is appropriate for practical
reasons.
- Addition of DFE makes a very large improvement. Appears that it may be
required for 300 meters?
- Results are 1E-9 BER, but Martin expects trends would be the same with
small dB offset.
- Package seemed to have more penalty impact than laser.
- Could be due to "step size" relative to data rate (8G to 4G more
significant in ratio and relative to data rate than 11G to 6G).
- Note - could also be due to steep 4th order function of package
model (I recall lasers are more typically 2nd order above ROF).
- What is overall budget and relative to what?
- With DFE, all combinations with fiber are less than 5 dB
(relative to "perfect" Tx, back to back).
- Perhaps penalties should be compared to -L, which is approximated by
the good/good cell. If this is done, then the worst penalty on slide 13
is 1.1 dB. Said differently, 4 dB back to back penalty relative to -L
(slide 8 bad/bad vs. slide 8 good/good) results in 1.1 dB EDC penalty at
end of channel (see slide 13, same cells).
- Very encouraging results.
- These penalties are data dependent and do not include RIN or other
jitter.
- Very interesting observation is that penalty impact of TP2 is same
whether back to back or with fiber.
- May help in developing a test that does not need fiber (such as -L
test in 802.3ae).
- Cost drivers
- Large number of variables possible.
- Need cost trends to direct simulation (and experimental) efforts.
- Cost trends will be vendor dependent.
- Laser chip yield.
- Packaging costs.
- Laser driver costs and yields.
- Others?
- TP2 test metrics
- Mask test only would be nice, but concern that it does adequately
constrain all degradations.
- Some degradations will not be correctable (by EDC) whereas some
would be.
- Therefore penalty impacts will be different. Mask cannot
distinguish.
- This will be more true if specs become more relaxed.
- Re-stated that low test cost/complexity is important - test cost
cannot increase more than other savings.
- Folks need to consider appropriate test metrics now.
- Simulation work (i.e., Intel work) should calculate test
metrics to see how well they track and predict
penalties.
Next work
- Questions for Intel
- How were EDC coefficients were determined and how BER was calculated
(see hanberg_1_0304.pdf)?
- Where does fiber used line up in the Cambridge set? What cumulative
percentage does it represent of the installed base?
- Why are some results in slide 13 better than ideal PIE-D?
- Modeling should consider.
- RIN.
- Lasers with overshoot and ringing.
- More realistic electrical drive modeling to include reflections.
- Other tap combinations.
Next call (8/26, 9 AM Pacific time)
- Cost vs. performance studies (Opnext, Bookham)?
- Other presentations encouraged.
- Cost trends
- Penalties and test metrics vs. parameters (and try to relate to cost
trends)
- Clarification of budget - how much can be available for TP2-related
degradations?
- TP2 test metrics.
Comments?
Thanks,
Tom Lindsay ClariPhy Communications tlindsay@ieee.orgphone: (425)
775-7013 cell: (206) 790-3240
----- Original Message -----
Sent: Tuesday, August 17, 2004 8:48
PM
Subject: [10GMMF] Reminder for TP2
call, 8/19/04
Meeting details (same numbers as before):
-
Date: Thurs, 8/19/04 (regular
day/time)
-
Time: 9:00 AM
-
Duration: 1:00 goal, 1:30 max
-
Number: 401-694-1515
-
Access code: 421721#
Topics
-
Approve agenda
-
Approve previous minutes
-
Presentations/results?
-
Cost vs. performance studies (Intel,
Opnext, and Bookham?)
-
Non-linear laser effects (Agilent?)
-
Others?
-
TP2 test
metrics
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