Re: [10GMMF] Task 2 and 4- launch recommendations discussion rev0.1 following Dec15th meeting
Thanks for your helpful comments Paul
I'd like to encourage comments on the reflector, to help progress between meetings, so this is excellent;
I think I'll quasi-formally update the table after task2 & 4 weekly calls, since that will give the groups a chance to review inputs hope that's an acceptable approach ?
I also would think some EF measurements of different launches would be useful to make sure we get theory and practise well aligned
many thanks
Jonathan
tel: 1 408 524 5110
e-mail: jking@bigbearnetworks.com
fax: 1 408 739 0568
Jonathan King
Director, Optical Systems
BigBear Networks
345 Potrero Avenue
Sunnyvale, CA 94085
-----Original Message-----
From: owner-stds-802-3-10gmmf@ieee.org [mailto:owner-stds-802-3-10gmmf@ieee.org] On Behalf Of Paul Kolesar
Sent: Thursday, December 16, 2004 12:58 PM
To: STDS-802-3-10GMMF@listserv.ieee.org
Subject: Re: [10GMMF] Task 2 and 4- launch recommendations rev0.1 following Dec15th meeting
Jonathan,
I agree that the table contents are what we agreed on the call yesterday. In looking more closely, I note that one of the values for OM1 launch appear to allow launches way outside those produced by compliant 62.5 um offset launch patch cords. I will suggest an adjustment based on Joerg's Encircled Flux plots.
The Encircled Flux definition for OM1 is correct on the 24 um radial limit for 86% EF. However, it does not properly reflect the allowed power near the core center. We touched briefly on this at the end of the call, but did not have the chance to think it thru at that point. Now, with the time to look more closely, I see a clear need for adjustment. If left as is, the proposal allows singlemode launches offset by as little as 5 um! According to Joerg's EF calculations, for OSL cords with 20 +/- 3 um offsets, no compliant cord would produce 30% EF until the encircled radius expanded beyond 10 um. At the presently suggested 4.5 um radius, the maximum allowable EFshould be about 8%. A number of better radius-percentage combinations are possible. Avoiding the crowded region on Joerg's plots when EF is less than 10% leads to consideration of values between 10 and 30%. It appears that either <20% in 7.5 um or <30% within 10 um radius are good combinations. The latter!
percentage has the advantage of being consistent with the proposed OM2 and OM3 specs on the inner region power, so is my recommendation. Please replace the present values with "<30% in 10 um radius".
I invite discussion to drive consensus.
Regards,
Paul Kolesar
SYSTIMAX® SOLUTIONS
1300 East Lookout Drive
Richardson, TX 75082
Phone: 972.792.3155
Fax: 972.792.3111
eMail: pkolesar@systimax.com
Jonathan King <jking@BIGBEARNETWORKS.COM>
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12/15/2004 09:32 PM
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Re: [10GMMF] Task 2 and 4- launch recommendations rev0.1 following Dec15th meeting
Dear Task 2 and 4 participants
Thanks to all for a very rich and useful discussion today
here is a revised slide of the 'primary' launch recommendations with
amendments agreed during the Dec 15th call
Please let me know if I've missed anything, or if you have comments or
suggestions
best wishes
Jonathan
tel: 1 408 524 5110
e-mail: jking@bigbearnetworks.com
fax: 1 408 739 0568
Jonathan King
Director, Optical Systems
BigBear Networks
345 Potrero Avenue
Sunnyvale, CA 94085