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[10GMMF] Concluded comment discussions on TP2 calls

Nick -
This email captures the comment resolution discussions held on the last two TP2 con-calls, and represents the attendance of those calls. Specifically, see the proposed resolutions given below in blue text.
Tom Lindsay & TP2 ad hoc group
phone: (425) 608-0209, or (949) 480-9210
cell: (206) 790-3240
  • Comment 49 & 50
    • No disagreement that overshoot masks should be relaxed. Lew was not on call to present his view that overshoot masks should be eliminated, so final value decision was deferred. Plan to discuss next week.
    • Propose accept in principle. Set Y3 = 0.8.
    • Re-raised concern that absolute overshoot power may need to be limited for Rx linearity. No specific proposals were given, and no specific comment was submitted, so this is a potential future item.
  • Comment 81 & 83
    • Recalled that prbs pattern is for component level testing. Normative test will use a subpattern from AnAi or BnBi.
    • Agreed that final prbs pattern must be better defined, preferably referencable through another standard.
    • Agreed that final prbs pattern should be convenient, preferable built-into pattern generators.
    • It is understood that prbs7 is probably not adequate, but more work is required to determine the best option. Work is planned (see TP2 notes).
    • Discussion about insertion of extra zero to balance prbs pattern not conclusive.
      • Agilent has reported that "zero-insertion" is standard on new equipment.
    • Idea was raised to insert long(er) runs of 1's and 0's into pattern to stress lower frequency impairments. Not concluded.
    • Plan to discuss again next week.
    • Propose accept in principle. In table 68-5
      • Change 2^7-1 PRBS to 2^9-1 PRBS.
      • Add footnote to table 68-5 '2^9-1 PRBS': 'A suitable pattern may be generated by the polynomial x^9+x^5+1 as specified in ITU-T V.52. The data sequence d(n) is given by d(n)=d(n-9)+d(n-5), modulo 2. The pattern is not inverted such that there is a run of nine ones in its length of 511 bits.'
      • Add another sentence 'A balanced pattern with one additional bit is also acceptable.'
  • Comment 104
    • Okay.
    • Propose accept.
  • Comment 105
    • Okay, but final pattern is TBD. Experimental work is planned to evaluate samples per UI, but 7 appears adequate at this time.
    • Propose accept  regarding sample count.
    • Propose accept in principle regarding pattern. Change 2^7-1 PRBS to 2^9-1 PRBS, as defined in Table 68-5, ... .
  • Comment 106
    • Okay.
    • Propose accept. For the figure, I suggest we use "Test figure" that I submitted with my comments, except:
      • Locate the TP2 arrow at the output of the patchcord (per comment 111 by Lew).
      • Replace "Signal Analyzer" with "Oscilloscope".
      • Replace the histogram plot figure with the block presently in Figure 68-5 labeled "Analysis...".
      • In the DUT block, add "Test pattern 1 or 2^9-1 PRBS".
  • Comment 109
    • Okay. Waiting to discuss MATLAB code 1/20 on TP2 call. Editorial format for the code, including scope of comments, should follow precedence of other standards (clause 40). TL - clause 40 appears to have minimal comments.
    • Propose accept. Code to be exactly as distributed by Norm Swenson for review for two recent TP2 calls. Insert at Figure 68-6.
  • Comment 111
    • Okay, but final pattern is TBD.
    • Propose accept in principle. Comment overtaken by comment 106.
  • Comment 107
    • Spirit of comment is good.
    • Need noise <<N0 of simulated Rx white noise density.
    • Jan Peeters Weem to test effect of noise in lab and run through MATLAB code, report on 1/20 call.
    • TL - some follow-on discussion are occurring with good progress. Expect to conclude next week. A recommended # of averages value may be given, leaving an actual number of averages up to the tester.
    • Propose accept in principle. Agreed text is "Averaging should be used to avoid a pessimistic estimate of TWDP."
  • Comment 108
    • Okay. Crosstalk from asynchronous Rx should be removed by averaging, so requirement for simultaneous operation should not be not necessary.
    • Propose accept.
    • Future topic - does crosstalk get measured/included in RIN test?
  • Comment 110
    • Okay. Location and format of the informative section not clear. Editor's preference, but should follow precedence of other standards, perhaps clause 40. Comment suggest appendix, since body of standard should focus on normative material.
    • Propose accept in principle.
      • Instead of an annex, the TP2 group proposes to put text in body of document adjacent to Figure 68-6. I propose it be subclause The title of the subclause should be "Description of the TWDP processing algorithm".
      • In document, replace "annex" with "text".
      • "Laser response" in Figure 1 of document should "TP2 transmitter response".
      • Beyond this, I believe the editor will be able to apply the appropriate formatting.
Please respond if I errored in recording these discussions or conclusions.