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Dear Pete,
Thank You for the feedback. Indeed, it seems that the
values expressed on uW OMA are overcomplicated. Initially, the values were
designated as average powers and only then OMA was added in the description
without changing the formula respectively. I feel guily for not having seen that
before.
The cells B41, B44 and B46 are the only ones affected by
this particular problem in version 2.1. Version 2.2 will have this problem
eliminated.
regarding the TDP and ITU_Optical_Path_Penalty - I do not
see a problem setting the TDP to a default value of 3 dB, which seems to be
aligned with the discussion on the TDP values headed by Hamano-san. The path
penalty was however assumed to be 1 dB in out current power budget estimations
and I would rather it stayed the way it is defined right now. Otherwise, I feel
some people may get confused ...
Thank You for the feedback
Marek
Hajduczenia (141238)
NOKIA
SIEMENS Networks S.A. – COO BBA DSLAM R&D
Rua
Irmãos Siemens, 1, Ed. 1, Piso 1
Alfragide, 2720-093 Amadora,
Portugal
*
marek.hajduczenia@nsn.com
(+351.21.416.7472 4+351.21.424.2082
Marek,
Looking at
3av_0711_linkmodel_v2_1.xls, I have a couple of
comments.
Cells B41, B44, B46
are all OMA power levels in uW.
The formula in cell
B44 is “=1000*10^(B43/(2*(10^(B4/10)-1)/(10^(B4/10)+1))/10)” which corrects
for the ER (B4).
Since these values
are OMA rather than average power, shouldn’t this be simply
“=1000*10^(B43/10)”?
Secondly, since TDP
includes dispersion penalty, it would be a good idea if the example value for
TDP was larger than the value for
ITU_Optical_Path_Penalty.
e.g. TDP = 3 dB,
ITU_Optical_Path_Penalty = 2 dB
Regards,
Pete
Anslow
Nortel Networks UK Limited, London Rd, Harlow,
Essex CM17 9NA, UK
External +44 1279 402540 ESN 742
2540
Fax +44 1279 402543
From:
Hajduczenia, Marek [mailto:marek.hajduczenia@NSN.COM]
Sent: 03 December 2007 08:48
To:
STDS-802-3-10GEPON@LISTSERV.IEEE.ORG
Subject: [8023-10GEPON] [Channel Link
Model] Suggestions for version 2.1
following the
current development of the channel link model spreadsheet for the 802.3ba
group (former HSSG), I would like to suggest the following changes to the
current version of our approved channel link model spreadsheet version
2.1:
1. add IEEE_Tx_OMA_Min and
IEEE_Tx_OMA_Max expressed in both uW and dBm, which will facilitate the
filling of the tables in Clause 91
2. produce Visual Basic
macros for calculation of the dispersion penalty, fibre channel attenuation
and fibre dispersion
If there are any more
suggestions to extend the functionality of the current version of the
spreadsheet, I would appreciate feedback on the reflector. The model is only
as good as the people who revise it and use it in practice.
Thank You for Your
attention and time.
Marek
Hajduczenia (141238)
NOKIA SIEMENS Networks S.A.
– COO BBA DSLAM R&D
Rua Irmãos Siemens, 1, Ed.
1, Piso 1
Alfragide, 2720-093 Amadora, Portugal
*
marek.hajduczenia@nsn.com
(+351.21.416.7472 4+351.21.424.2082
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