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Re: [10GMMF] TP3 meeting Agenda Oct 19

TP3 folks - the last slide of Lew's proposals, discussed on the TP3 call last week, involved rise/fall times. Here's my understanding of this topic and something to discuss 10/26.
  1. If I understand correctly, the purpose of Petre's work is to develop multi-tap filters to emulate subsets (currently 3: pre-,post-,~symmetrical) of the Cambridge fiber set. It's purpose to date has not been to define complete and final TP3 test signals.
  2. To match the channel emulator to the Cambridge fiber set, faster rise/fall times are more accurate, but some slowing is appropriate to filter the 18 mode groups down into something more practical such as 5 taps. The filtering also helps average the wide sets of pre, post, and centered-cursor channels from the Cambridge models down to 3 emulator setups. My gut (not scientific) says that 30 psec is reasonable for this work. Note, all of this matching work is analytical and does not require an actual E/O source.
  3. The actual TP3 test signal will be the convolution of these channel emulators and other test equipment including the pattern generator, the E/O source, and any additional wave-shaping or filtering that we define. This TP3 test signal should represent the appropriate worst case combination of the fibers and real TP2 sources we expect to find/allow in application, and it should line up with the TP2 and dispersion penalty value in the budget (see slide 11 in http://grouper.ieee.org/groups/802/3/aq/public/upload/TP2-TP3-budgetandimplications19Oct.pdf).
  4. I thought the (min value of) 47 psec applied only to the optical "source" of the TP3 test signal - that is, everything but the channel emulators. I'm assuming this source will be essentially Gaussian and correctable. Since this source is trying to represent real transmitters, including non-correctable impairments, I believe it should be some amount greater than 47. The actual value is TBD from TP2 work.
  5. Petre's method uses a MMSE approach integrated over the pulse shape for calibrating the channel emulators to the desired shapes. We may also be able to use such a method to adjust the source rise/fall times once combined with the channels.
 
Tom
 
----- Original Message -----
Sent: Monday, October 18, 2004 9:19 AM
Subject: [10GMMF] TP3 meeting Agenda Oct 19

Dear TP3'ers,

Here is the agenda for tomorrows meeting:-

Tuesday October 19th at 9am SJ, 5pm UK, 6pm Germany
Dial in (650) 599-0374, Meeting ID:     136169

        1. List Attendees
        2. Review meeting notes from last week
        3. Review Lew's additional motions (which were not heard at Ottawa). These were forwarded by Lew last week.
        4. TP2/TP3 link budget work. Tom Lindsay's Feedback from TP2 call

Upcoming items of focus (for subsequent metings):-
        i) Static channel methodology
                - noise loading
                - channel types and exact characteristics
                        o i.e. do we pick pre, post cursor and quasi symmetric and if so where from? 108 fiber model?
      ii) OMA measurement methodology.

Best Regards

Mike