Transcript ppt00028.ppt

IEEE802.3aq Channel model ad hoc
Task 2: Time-varying study & modal noise
Teleconference notes, 8 Dec 2004
Jonathan King
8 Dec 2004
IEEE802.3aq Channel model ad hoc
Task 2: Time-varying study & modal noise
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Agenda
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Attendees
Agree last meetings minutes
Task 2
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Launch study, joint task 2 & task 4
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no agenda items
Joerg Kropp - OM3 simulations and experiment
David Cunningham - PIE-D measurements on OM3 fibres
other business
next meeting date/time
8 Dec 2004
IEEE802.3aq Channel model ad hoc
Task 2: Time-varying study & modal noise
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1) Attendees
8 Dec 2004
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Jonathan King, Big Bear Networks
Yu Sun, Optium
John Jaeger, Big Bear Networks
Joerg Kropp, Infinion
David Cunningham, Agilent
Sudeep Bhoja, Big Bear Networks
John Ewen, JDSU
John Abbott, Corning
Jim Morris, DOC
Al Brunsting, Panduit
Andre van Schyndel, Bookham
Jonathan Ingham, Cambridge
Pete Hallemeier, Optium
Lew Aronson, Finisar
IEEE802.3aq Channel model ad hoc
Task 2: Time-varying study & modal noise
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2) Agree last meetings minutes
Peter Hallemeier and Joerg Kropp asked to be added to the attendee list; no other
comments
3) Task 2 - no agenda items
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4) Launch study, joint activity task 2 & 4 - 1
a) OM3 simulations and experiment - Joerg Kropp
Modeled OM3 DMD and bandwidths were compared with measurements on 3 recently made
OM3 fibres for CL and OSL (connector offsets were not included in calculations). An alpha-p fit
of 2.09 was derived by comparing modeling and experimental results. Calculations showed that
a good single mode spot launched into ideal OM3 resulted in good transmission for both CL and
OSL, but if a wider core area was excited, OSL bandwidth collapsed and CL gave best
transmission. Experiments showed significantly better transmission for CL.
Discussion following
John Abbott noted that the typical alpha-p value wouldn't necessarily reflect worst case fibres.
Joerg Kropp commented that he thought that OSL would be challenging in the presence of
connector offsets.
b) PIE-D measurements on OM3 fibres - David Cunningham
Presented measurements of PIE-D metrics on recently made 300m OM3 fibres for CL and OSL
(with and without 7um MM-MM connector offsets included). Results showed that single mode
CL was lowest PIE-D both with and without connector offsets. It was also noted that an ROFL
launch (also a centre launch) gave significantly higher PIE-D values than single mode CL. It
was noted that OM3 fibre characteristics were fairly consistent fibre to fibre, so these results
were expected to be representative of modern OM3 fibres.
8 Dec 2004
IEEE802.3aq Channel model ad hoc
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4) Task 2 & 4: joint activity on launch study - 2
a) PIE-D measurements on OM3 fibres - David Cunningham
Discussion following
The possibility of a high offset launch was discussed, David Cunningham said that although
PIE-D metrics peaked at 10-12um, higher offset OSL >17um would introduce significant mode
selective loss and modal noise issues.
Joerg Kropp commented that an OSL on OM3 would be challenging in the presence of
connector offsets.
Al Brunsting offered to present measured data on significant sample sizes of commercial
connectors at the next meeting
John Jaeger offered further measurements on OM3 fibres for 15th Dec.
There was some discussion on launch compliance tests. There was some support for
appropriate encircled flux type specifications for CL and OSL. CPR (Coupled Power Ratio)
measurement was also discussed for direct centre launch into MMF, as a test to ensure a single
mode launch at the transponder was compatible with a mode conditioning patchcord.
Other Discussion points
OM2 fibre model - a task 1 meeting is scheduled for 16th December next week
It was agreed that Jonathan King should draft up launch and launch compliance test templates
for each fibre type, including a line for a common launch for all fibre types to help structure the
range of launch selections and recommendations by this study group
8 Dec 2004
IEEE802.3aq Channel model ad hoc
Task 2: Time-varying study & modal noise
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4) Other business - no issues raised
5) Next meeting
• Wednesday 15th December 2004 9.30am PCT
8 Dec 2004
IEEE802.3aq Channel model ad hoc
Task 2: Time-varying study & modal noise
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