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I have a conflict and can't be at the task 2 meeting today. Maybe we can hit this on the task1 tomorrow.
If Petar Pepeljugoski or Paul Kolesar are on, they will be able to address this a little.
The OM3 802.3aq Monte Carlo set with OM3 1300nm delays was generated from the TIA OM3 850nm Monte Carlo set by Petar, and I agree with the expedient way Petar generated a set of 1300nm delays consistent with the 850nm delays.
However, the TIA OM3 data set was not created to mimic the installed base of OM3 fibers. It was generated to develop the OM3 specification and to reasonably certain that the specification would separate passing from failing fibers. Unlike the 802.3aq OM1 (FDDI) Monte Carlo set, it does not agree with production data, and in fact has many fibers with OFL BWs which are somewhat unphysically high.
For purposes of testing the offset launch with OM3 fibers, the OM3 Monte Carlo set should be correctly including the inherent DMD slope at 1300nm for a fiber optimized at 850nm, and if this slope is big enough to cause an EDC issue, then the data set should show this consistent effect.
However, in asking whether there is an issue with center launches (with or without connectors) I am not sure that the OM3 Monte Carlo set mimics production distributions. Petar, Paul, and others in TIA will recall that we actually tinkered with the OM3 distribution to assist Petar in the ISI simulations (to balance the number of fibers passing vs failing) independent of whether that was seen in manufacturing.
I am not sure there is a problem but the numbers Jonathan King is seeing in the testing of the OM3 demo cable (for center launches and center launches with offset) seem high compared to what John Ewen got with the OM3 Monte Carlo set - and this might be one explanation.