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Mike,
The spreadsheet assumes the worst case is the 0101010 pattern which is described by cosine. However, the transition is described as erf function. This signal still has large ISI on the neighboring bits, as well as larger MPN SD than the 0101010 case, shown in the slides by David, as well as mine. I think (David can confirm or say otherwise) is able to analyze limited number of patterns at once, so he took the 00001111 transition. The analysis also looked at what happens to the MPN SD as you change the ISI on the neighboring bit, and what the presentation says is that the MPN SD grows with the ISI in this case (and ISI is proportional to OMA).
So, to answer your question, the bit experiencing the ISI has lower signal value and increased MPN SD than the 0101010 case.
The word document concentrates on just the center of the bit interval and calculates the BER directly, not through penalties.
The difference between David and myself was what is MPN SD proportional to, and the joint work showed it is proportional to the ISI, and therefore to the OMA.
This is the reason for the conclusion that we do need a change as I proposed back in December.
Of course, the simulation is able to analyze all patterns at once.
I hope I will be able to answer all of your questions at tomorrow's call.
Regards,
Peter
Petar Pepeljugoski
IBM Research
P.O.Box 218 (mail)
1101 Kitchawan Road, Rte. 134 (shipping)
Yorktown Heights, NY 10598
e-mail: petarp@xxxxxxxxxx
phone: (914)-945-3761
fax: (914)-945-4134
Mike Dudek ---07/05/2012 05:10:03 PM---I’m afraid I won’t be able to attend at least the first part of Friday’s meeting. I do have a quest
From: Mike Dudek <mike.dudek@xxxxxxxxxx>
To: Petar Pepeljugoski/Watson/IBM@IBMUS, Jonathan King <jonathan.king@xxxxxxxxxxx>,
Cc: "Amezcua, A. (Adrian)" <adrian.amezcua@xxxxxxxxx>, Anthony Torza <anthony.torza@xxxxxxxxxx>, "a_flatman@xxxxxxxxxxxxx" <a_flatman@xxxxxxxxxxxxx>, Brad Booth <Brad_Booth@xxxxxxxx>, David Cunningham <david.cunningham@xxxxxxxxxxxxx>, Daniel Dove <ddove@xxxxxxx>, Ephrem Wu <ephremw@xxxxxxxxxx>, "Bernstein, Gary" <GBernstein@xxxxxxxxxxx>, "Gary Nicholl (gnicholl)" <gnicholl@xxxxxxxxx>, Harry Fu <harryf@xxxxxxxxxx>, Jack Jewell <jack@xxxxxxxxxxxxxx>, Jeffery Maki <jmaki@xxxxxxxxxxx>, John Petrilla <john.petrilla@xxxxxxxxxxxxx>, Keith Nellis <knellis@xxxxxxxxx>, Lian Zhao <lzhao@xxxxxxxxx>, Martin Gilpatric <marting@xxxxxxxxxx>, "mnowell@xxxxxxxxx" <mnowell@xxxxxxxxx>, Oren Sela <orens@xxxxxxxxxxxx>, "Anslow, Peter" <panslow@xxxxxxxxx>, Piers Dawe <piers.dawe@xxxxxxxxxxxxx>, "Kolesar, Paul" <PKOLESAR@xxxxxxxxxxxxx>, Robert Coenen <rcoenen@xxxxxxxxxxxxxxxxxxx>, "Rick.Pimpinella@xxxxxxxxxxx" <Rick.Pimpinella@xxxxxxxxxxx>, "ryan.latchman@xxxxxxxxxxxxx" <ryan.latchman@xxxxxxxxxxxxx>, Sudeep Bhoja <sbhoja@xxxxxxxxxxxx>, Shmuel Levy <shmuel@xxxxxxxxxxxx>, Scott Kipp <skipp@xxxxxxxxxxx>, "STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx" <STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx>, "Swanson, Steven E" <SwansonSE@xxxxxxxxxxx>, Vipul Bhatt <Vipul_Bhatt@xxxxxxxx>
Date: 07/05/2012 05:10 PM
Subject: RE: [802.3_100GNGOPTX] MMF Ad Hoc meetings: MPN discussion reminder
Jonathan,
David and I have been working together to address the action item from last Friday's teleconference on mode partition noise. David put together several slides to summarize our joint investigation. In David's absence I will make the presentation. We will continue with our investigation.
The presentation is attached below.
In summary:
- The spreadsheet model assumes that 0101010 (0001000) pattern is the worst, which is not. A different pattern was used to find the worst case (00001111 instead of 0001000).
- When this condition is removed (as it should be), simulation results and analytical link model agree.
- Last graph in the attached pdf presentation indicates dividing the MPN SD by ISI is a good first approximation to the required correction of the spreadsheet.
- Calculations assume k is constant
For those interested, I am also attaching a word document describing the test cases we ran and a modified Excel spreadsheet with those examples.
Regards,
Peter
(See attached file: SD of MPN Davids Comments.pdf)
(See attached file: Correctness of MPN treatment v1a.docx)
(See attached file: 10GEPBud3_1_16a_25G illustration for david1.xls)
Petar Pepeljugoski
IBM Research
P.O.Box 218 (mail)
1101 Kitchawan Road, Rte. 134 (shipping)
Yorktown Heights, NY 10598
e-mail: petarp@xxxxxxxxxx
phone: (914)-945-3761
fax: (914)-945-4134
"Jonathan King" ---07/05/2012 03:33:20 PM---Dear all,
From: "Jonathan King" <jonathan.king@xxxxxxxxxxx>
To: <STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx>, "David Cunningham" <david.cunningham@xxxxxxxxxxxxx>, Petar Pepeljugoski/Watson/IBM@IBMUS,
Cc: <a_flatman@xxxxxxxxxxxxx>, "Amezcua, A. (Adrian)" <adrian.amezcua@xxxxxxxxx>, "Anslow, Peter" <panslow@xxxxxxxxx>, "Anthony Torza" <anthony.torza@xxxxxxxxxx>, "Bernstein, Gary" <GBernstein@xxxxxxxxxxx>, "Brad Booth" <Brad_Booth@xxxxxxxx>, "Daniel Dove" <ddove@xxxxxxx>, "Ephrem Wu" <ephremw@xxxxxxxxxx>, "Gary Nicholl (gnicholl)" <gnicholl@xxxxxxxxx>, "Harry Fu" <harryf@xxxxxxxxxx>, "Jack Jewell" <jack@xxxxxxxxxxxxxx>, "Jeffery Maki" <jmaki@xxxxxxxxxxx>, "John Petrilla" <john.petrilla@xxxxxxxxxxxxx>, "Keith Nellis" <knellis@xxxxxxxxx>, "Kolesar, Paul" <PKOLESAR@xxxxxxxxxxxxx>, "Lian Zhao" <lzhao@xxxxxxxxx>, "Martin Gilpatric" <marting@xxxxxxxxxx>, <mike.dudek@xxxxxxxxxx>, <mnowell@xxxxxxxxx>, "Oren Sela" <orens@xxxxxxxxxxxx>, "Piers Dawe" <piers.dawe@xxxxxxxxxxxxx>, <Rick.Pimpinella@xxxxxxxxxxx>, "Robert Coenen" <rcoenen@xxxxxxxxxxxxxxxxxxx>, <ryan.latchman@xxxxxxxxxxxxx>, "Scott Kipp" <skipp@xxxxxxxxxxx>, "Shmuel Levy" <shmuel@xxxxxxxxxxxx>, "Sudeep Bhoja" <sbhoja@xxxxxxxxxxxx>, "Swanson, Steven E" <SwansonSE@xxxxxxxxxxx>, "Vipul Bhatt" <Vipul_Bhatt@xxxxxxxx>
Date: 07/05/2012 03:33 PM
Subject: RE: [802.3_100GNGOPTX] MMF Ad Hoc meetings: MPN discussion reminder