[8023-10GEPON] ODP: [8023-10GEPON] FW: [8023-10GEPON] [POWER_BUDGET] ad hoc group meeting - CORRECTE D
Dear Eric,
Thank You for that well organized set of questions.
If You have a look at the new spreadsheet for 10G EPON systems, we will have a separate field for the splitter loss and the channel insertion loss (fibre loss, connectors etc). This is what is looks like right now:
Split_count= 16
Power Budget P= 27,5 dB
Connections etc 2,0 dB
Add Ins Loss 14,0 dB
PwrBud-Conn-AIL 11,4 dB
Where Power Budget P is a simple difference between Tx pwr OMA and NomSensOMA. The PwrBud-Conn-AIL field seems to estimate the difference between the available power budget and the already assigned loss for the channel insertion (here 14 dB for 1x16 splitter and 2,0 dB for addition loss). We could therefore start with the channel insertion loss (which would be a straightforward task), fix the additional acceptable loss for connectors/splices and fibre channel itself and then we will be left only with the penalty allocation which is more tricky. I think we may figure out some number to put in here but no matter what we do there are too many variables to account for.
The opposite way is even less attractive - we do not know where the fix the laser output power (somewhere below 10dBm I guess) and we do not know what sensitivity we can achieve easily on the Rx side (-16 ?? for PIN, -24 ?? for APD) so we may not want to go that way ...
I would vote personally for the first option thus make sure we identify the elements of the channel insertion and penalty allocation elements and then associate them with the specific values ...
Best wishes
Marek
________________________________
Od: Eric Lynskey [mailto:eric.lynskey@TEKNOVUS.COM]
Wysłano: Wt 1/30/2007 1:59
Do: STDS-802-3-10GEPON@listserv.ieee.org
Temat: Re: [8023-10GEPON] FW: [8023-10GEPON] [POWER_BUDGET] ad hoc group meeting - CORRECTE D
Although I haven't looked at the ITU-T slides yet, both versions of the
802.3 slides seem to be very similar.
For reference, I'll also point to Figure 2 of this paper:
http://literature.agilent.com/litweb/pdf/5988-5908EN.pdf.
The above paper shows both the power in OMA and in dBm, which is one of the
differences in the two slides. It also shows the differences between the
stressed receiver sensitivity and nominal receiver sensitivity. Another
difference is that in Mike's slide, he adds in some unallocated margin.
Perhaps someone else can chime in on the history behind this, but it looks
like there was some unallocated margin ("additional insertion loss allowed")
provided for 10GBASE-S, 10GBASE-E, and 10GBASE-LX4 links. For 10GBASE-L,
there is none specified. As best I can tell, no additional loss was defined
for 1000BASE-PX links. Does anyone have a better understanding of this?
Right now, the spreadsheet adds three variables to determine the total
channel insertion loss:
ChIL = Penalty from connections + Penalty AddIn Loss + Fiber attenuation
By varying these three items, you can get the maximum channel insertion loss
up to 29dB. Note that right now, the only AddIn Loss (cell L8) is that of
the splitter.
The power budget, as calculated by the spreadsheet, is a function of only
two values:
Power Budget = Tx Power (OMA) - Rx Sensitivity (OMA)
However, we also know that the power budget is a function of the channel
insertion loss and all of the other penalties:
Power Budget = ChIL + All other Penalties
If we start by fixing at least one of these values, such as the Channel
Insertion Loss, it will certainly help narrow down what is left.
- Eric Lynskey
-----Original Message-----
From: Mike Dudek [mailto:mike.dudek@PICOLIGHT.COM]
Sent: Monday, January 29, 2007 9:45 AM
To: STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON] FW: [8023-10GEPON] [POWER_BUDGET] ad hoc group
meeting - CORRECTE D
I see a number of problems with the diagram for IEEE. Attached is a
modified version of how I believe the spreadsheet used for 10GBE works.
(sorry if I'm out of date on what spreadsheet is being used for
10GEPON).
Regards,
Mike Dudek
Director Transceiver Engineering
Picolight Inc
1480 Arthur Avenue
Louisville
CO 80027
Tel 303 530 3189 x7533.
mike.dudek@picolight.com
-----Original Message-----
From: TATSUTA [mailto:tatsuta@ANSL.NTT.CO.JP]
Sent: Monday, January 29, 2007 4:44 AM
To: STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON] FW: [8023-10GEPON] [POWER_BUDGET] ad hoc
group meeting - CORRECTE D
Dear Robert and Marek,
Thank you for your arrangement.
I have some opinions about this issue.
I think our target is 29dB maximum insertion loss so far (See a result
of the straw poll in November meeting, which is described in page 6 and
8 of http://www.ieee802.org/3/av/public/2006_11/3av_0611_closing.pdf).
So, at first, we need to decide the power budget, and it is derived from
the spread sheet which Marek is making now.
I made a slide which described a relation between some numbers, which
were defined in Tanaka-san presentation in November, and the spread
sheet.
Also, I made a slide which described ITU-T terminology for your
information.
Can we start to define the power budget?
Sincerely yours,
Tsutomu TATSUTA
At 00:47 07/01/27, Lingle, Jr, Robert (Robert) wrote:
>There was an error in my first email w/r/t to the time of the
Wednesday 1/31 >call. It will be held at 9AM to enable European
participation.
>***********************************************************************
*****
>************
>All,
>
>I appreciate the expression of interest I received in the Power Budget
ad >hoc from 10 individuals. I expect more than that to join the
calls.
>
>The first meeting will be held Tuesday, January 30 at 7PM EST, which I
>believe is >Wednesday January 31 at 9AM in Tokyo. This meeting would
likely be >attended by anyone in Japan, Korea, or the US West Coast.
>
>I will also hold a follow-up call on Wednesday January 31 at 9AM EST
>for anyone on the East Coast of the US or in Europe who wishes to
>participate. I believe that will be 2 or 3PM for Europe cities.
>
>Toll-free in US 866-263-8899
>Outside US 816-249-6061
>Conf. Code 7707985015
>
>I propose that the ad hoc will meet four times between now and March
>Plenary, with following goals:
>
>1/30 & 31 - purpose is to review a summary of results and conclusions
from >previously prepared materials, discuss what seem like most likely
solutions >for 29dB power budgets, and to generate questions that need
answers to turn >preliminary conclusions into consensus conclusions
based on cost and >technical feasibility. I am preparing that
presentation to review in >consultation with others. Ad hoc
participants will be expected to take >action items from the first
meeting to bring back answers to the questions >raised.
>
>week of 2/12 - purpose is to bring back answers to questions raised in
>previous meeting and debate their meaning, with goal of focusing down
on one >PMD proposal one which to analyze further for the 29 dB power
budget case.
>
>week of 2/26 - purpose is to finish up any unanswered questions for
29dB >power budget solution, and begin to discuss whether the 29 dB
solution can >form the basis for reduced cost PMDs for lower power
budget cases?
>
>week of 3/5 - review and revise a presentation for March plenary >
>Robert > >Robert Lingle, Jr.
>Fiber Design and Transmission Research >OFS Corporate R&D, Atlanta
>404-886-3581 (cell)
>770-798-5015 (office)