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Re: [802.3_100GNGOPTX] MMF Ad Hoc meetings: MPN discussion reminder



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


Inactive hide details for Mike Dudek ---07/05/2012 05:10:03 PM---I’m afraid I won’t be able to attend at least the first partMike 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





I’m afraid I won’t be able to attend at least the first part of Friday’s meeting.  I do have a question however on your joint paper with David.  I agree that the MPN is larger for the 00001111 pattern however the picture on slide 3 is clearly showing that the Amplitude of this transition is also higher at the sampling point.  Are you saying that the increase in MPN more than out-weighs this larger amplitude and you expect a larger error rate for this transition than for the 101010 transition?    I think that the Word document is also assuming that the MPN calculated in the spreadsheet is the same across the whole pulse and is independent of the pattern so I’m not surprised by the result that if that is true then it needs to be treated like RIN.     
 
 
Mike Dudek 
QLogic Corporation
Senior Manager Signal Integrity
26650 Aliso Viejo Parkway
Aliso Viejo  CA 92656
949 389 6269 - office.
Mike.Dudek@xxxxxxxxxx
 
 
From: Petar Pepeljugoski [mailto:petarp@xxxxxxxxxx]
Sent:
 Thursday, July 05, 2012 1:18 PM
To:
 Jonathan King
Cc:
 Amezcua, A. (Adrian); Anthony Torza; a_flatman@xxxxxxxxxxxxx; Brad Booth; David Cunningham; Daniel Dove; Ephrem Wu; Bernstein, Gary; Gary Nicholl (gnicholl); Harry Fu; Jack Jewell; Jeffery Maki; John Petrilla; Keith Nellis; Lian Zhao; Martin Gilpatric; Mike Dudek; mnowell@xxxxxxxxx; Oren Sela; Anslow, Peter; Piers Dawe; Kolesar, Paul; Robert Coenen; Rick.Pimpinella@xxxxxxxxxxx; ryan.latchman@xxxxxxxxxxxxx; Sudeep Bhoja; Shmuel Levy; Scott Kipp; STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx; Swanson, Steven E; Vipul Bhatt
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



Inactive hide details for "Jonathan King" ---07/05/2012 03:33:20 PM---Dear all,"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






Dear all,

There will be a teleconference call (voice only) this Friday morning (USA) to discuss recent work on MPN (mode partition noise) .

Call in details
USA: 866 654 5792
International: +1 832 445 3154
Conference code: 4085425032

Friday 6
th July  
Start time  8am PCT, 11am EST, 4pm UK
Duration: 90 minutes

Outline agenda (TBC)
8.00am attendees
8.05am ‘MPN modeling’
Kasyapa Balemarthy and Robert Lingle

Discussion

Wrap up
Close at 10.30am

Best wishes
Jonathan



From:
 Jonathan King
Sent:
 Tuesday, June 26, 2012 4:59 PM
To:
 STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx; 'David Cunningham'; Petar Pepeljugoski (petarp@xxxxxxxxxx)
Cc:
 a_flatman@xxxxxxxxxxxxx; Amezcua, A. (Adrian); Anslow, Peter; Anthony Torza; Bernstein, Gary; Brad Booth; Daniel Dove; Ephrem Wu; Gary Nicholl (gnicholl); Harry Fu; Jack Jewell; Jeffery Maki; John Petrilla; Keith Nellis; Kolesar, Paul; Lian Zhao; Martin Gilpatric; mike.dudek@xxxxxxxxxx; mnowell@xxxxxxxxx; Oren Sela; Piers Dawe; Rick.Pimpinella@xxxxxxxxxxx; Robert Coenen; ryan.latchman@xxxxxxxxxxxxx; Scott Kipp; Shmuel Levy; Sudeep Bhoja; Swanson, Steven E; Vipul Bhatt
Subject:
 RE: [802.3_100GNGOPTX] MMF Ad Hoc meetings: MPN discussion

Dear all,

There will be a teleconference call (voice only) this Friday morning (USA) to discuss recent work on MPN (mode partition noise) .

Call in details
USA: 866 654 5792
International: +1 832 445 3154
Conference code: 4085425032

Friday 29
th June.  
Start time  8am PCT, 11am EST, 4pm UK
Duration: 90 minutes

Outline agenda (TBC)
8.00am attendees
8.05am Recent work update: Petar Pepeljugoski

Discussion

Wrap up
Close at 10.30am

Best wishes
Jonathan