Marek
Hajduczenia (141238)
SIEMENS Networks S.A. - IC
COM D1 R
Rua
Irmãos Siemens, 1
Ed. 1, Piso 1
Alfragide
2720-093
Amadora
Portugal
*
Marek.Hajduczenia@siemens.com
http://marekhaj.easyisp.pl/index.php
(+351.21.416.7472 4+351.21.424.2082
From: David Piehler [mailto:dpiehler@ALPHION.COM]
Sent: quarta-feira, 10 de Janeiro de 2007 21:37
To: STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON] [Channel link model ad-hoc]
Dear Marek and
Tsutomu:
Here is the reference:
ECOC 2006, paper
We4.5.7:
Analysis on SRS-Induced
Performance Impairment of Downstream Data Signal in Video Overlay EPON
Systems
A. Agata | A. Murakami
| Y. Horiuchi
KDDI R&D
Laboratories Inc.,
To quote (and add to) the conclusion from the
paper:
…we have found that the impact of AC
crosstalk (from SRS) on downstream data signal (at 1490 nm) exceeds 0.1dB on average
only when these conditions as follows are satisfied simultaneously: (1)
PRF (optical launch power at 1550 nm) becomes
~18dBm or more, (2) RF video signal contains VHF component (that is operates in the ~<100 MHz
region), and (3) OMI (optical
modulation index) of the VHF component in the optical RF signal
becomes more than ~10%.
The authors show that
cross talk from a discrete RF tone in the video domain onto a baseband GbE
signal, can result in a power penalty. This is in addition to any loss in
optical power suffered by GbE signal due to SRS.
In the case of
10GEPON:
(1) The crosstalk would
be 1545(?)nm <-> 1550nm XPM instead of 1490(?)nm <-> 1550nm SRS.
The relative magnitude of these effects can be seen in M. R. Phillips, et
al., J. Lightwave Technol., vol.17,
(1999),
pp1782-1792.
(2) Instead of a ~ 10%
RF subcarrier at ~ 50 – 100 MHz, the RF “tones” (typically two) are in the
2 – 10 GHz range. The tones are chosen such that f1-f2, f1-2*f2, 2*f1-f2,
f1-2*f2, etc lie outside of the CATV signal band (50-870 MHZ). Typically
the frequencies of the tones may be in the 2 and 6 GHz ranges. The tones
can result from phase and or intensity modulation of the source laser, and the
resulting RF power is usually much higher than any one CATV RF sub
carrier. (Laser chirp + fiber dispersion rapidly convert pure phase
modulation into intensity modulation)
I have not carried out
experiment or attempted to calculate this effect. I will be in
David
Piehler
Alphion
mobile: +1 732 692
4581
From:
Sent: Wednesday, January 10, 2007 12:18
AM
To:
STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON] [Channel link
model ad-hoc]
Dear David,
Would You be so kind
and provide the complete reference for the said paper ? I am also curious but a
broad search is lengthy - I am sure we could benefit from this publication if we
could identify which one it is ..
Regarding the issue
number 2: what we are interested in is the impact of the video overlay signal on
the digital transmission rather than trying to model the RF channel transmission
in the 1550 nm band. The video overlay is not an obligatory part of the standard
and as far as I know, current IEEE 802.3 does not specify the parameters of the
video overlay apart from the statement that the 1550 nm band is reserved for
other services. As such, I believe that the 10G standard should go the same way
and focus on the EPON PHY rather than on the RF overlay specifications, which
are outside of the scope of our PAR.
Thank You for Your
comments. I would appreciate if You had a look at the modelling of the SBS and
SRS once the updates spreadsheet is released and shared Your thoughts with us
...
Best
wishes
Marek
Hajduczenia (141238)
SIEMENS Networks S.A. -
IC COM D1
R
Rua Irmãos Siemens, 1
Ed.
1, Piso 1
Alfragide
2720-093 Amadora
Portugal
*
Marek.Hajduczenia@siemens.com
http://marekhaj.easyisp.pl/index.php
(+351.21.416.7472 4+351.21.424.2082
From: TATSUTA
[mailto:tatsuta@ANSL.NTT.CO.JP]
Sent: quarta-feira, 10 de Janeiro de 2007
2:42
To:
STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON] [Channel link
model ad-hoc]
Dear David,
(1) I would
not be so quick to dismiss XPM. 々PM gets stronger as
delta lambda gets small, and at higher RF frequencies. ！t’s not well known but most
video signals have or less discrete, high modulation index, phase and/or
intensity tones in the 2 ？10 GHz range. ゝhese are used for SBS
suppression, and they vary significantly among vendors.？I
have not done any calculations, but there was a paper at ECOC this year from
KDDI that showed that cross-talk from RF carriers could add a penalty ？aside from power loss.
I
looked for a paper you suggested, but I did not find it.
Anyway, if it is
true, I agree with your comment.
(2) Is there any
need to define the acceptable degradation on the video signal?？This is perhaps the most
significant issue with the B/GPON RF video overlay.？I am not concerned with
power loss (or gain) but rather the effective increase in RIN (mediated by
either XPM or SRS), or by discrete RF interference from idle fames again
mediated by XPM and/or SRS.？(Incidentally would these idle
frames be in phase if you had several 10G DWDM signals originating from the same
switch/router?
I do not think it is an issue of the channel link model,
because we can not put it on the spread sheet and also it is an implementation
issue of RF-ONU.
However, if we can consider it when we decide the output
power level of 10GE-OLT and wavelength allocation of a downstream signal, it is
good for us.
Sincerely yours,
Tsutomu TATSUTA
At 02:02
07/01/10, David Piehler wrote:
Just a few comments
〓
(1)
I would not be so quick
to dismiss XPM. 〓XPM gets stronger as
delta lambda gets small, and at higher RF frequencies. 〓It’s not well known but
most video signals have or less discrete, high modulation index, phase and/or
intensity tones in the 2 〓 10 GHz range.
〓These are used for SBS
suppression, and they vary significantly among vendors.〓 I have not done any
calculations, but there was a paper at ECOC this year from KDDI that showed that
cross-talk from RF carriers could add a penalty 〓 aside from power
loss.
(2)
Is there any need to
define the acceptable degradation on the video signal?〓 This is perhaps the
most significant issue with the B/GPON RF video overlay.〓 I am not concerned
with power loss (or gain) but rather the effective increase in RIN (mediated by
either XPM or SRS), or by discrete RF interference from idle fames again
mediated by XPM and/or SRS.〓 (Incidentally would
these idle frames be in phase if you had several 10G DWDM signals originating
from the same switch/router?
I am not trying to open a big can of
worms here, and my feeling is that these effects are probably negligible,
although measurable.
David
Piehler
Alphion
mobile: +1 732 692 4581
From:
Sent: Tuesday, January 09, 2007 3:56
AM
To:
STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON] [Channel link
model ad-hoc]
Dear
Tatsuta-san,
Thank You very much for Your contribution. I found it useful
and if there is no problem with it, I would like to reuse part of Your
conclusions in the introductory section of the presentation on the ad-hoc
activities.
I agree with Your conclusions and I believe that the updated
Excel spreadsheet will contain SBS and SRS power penalties - SRS is completed
while SBS is still under examination to achieve 0 - order approximation with
reasonable quality.
The
presentation will be distributed today and I will ask for the potential
supporters of the conclusions and implementation.
The updated Excel
spreadsheet will also be distributed in due time on the reflector
...
Best
wishes
Marek
Hajduczenia (141238)
SIEMENS
Networks S.A. - IC COM D1 R
Rua
Irm〓os Siemens,
1
Ed. 1, Piso 1
Alfragide
2720-093 Amadora
* Marek.Hajduczenia@siemens.com
http://marekhaj.easyisp.pl/index.php
(+351.21.416.7472
4+351.21.424.2082
From: TATSUTA
[mailto:tatsuta@ansl.ntt.co.jp]
Sent: ter〓a-feira, 9
de Janeiro de 2007 6:32
To:
Subject: Re: [8023-10GEPON] [Channel link
model ad-hoc]
Dear Marek and all,
I summarized the
influence of RF signal as attached.
My conclusion is following;
1. SRS
and SBS should be studied.
2. XPM does not need to be considered, if a
wavelength of 10G-EPON downstream is separated in 5nm or more from RF signal
wavelength.
3. The other items do not need to be considered, unless S/X value
of ONU input point is specified in the standard body (I do not think we specify
it.). I think S/X is implementation issue.
Sincerely yours,
Tsutomu
TATSUTA
At 21:41 07/01/04,
Dear Sergey,
I
would appreciate any help You can provide me with. I have some formulas to
estimate the impact of the video channel overlay on the downstream and upstream
channels but I have a very hard time trying to figure out how to calculate /
estimate the values of individual parameters.
Do You have any idea how to
apply the formulas with the set of parameters that we have in the Excel
spreadsheet?
Best wishes
Marek Hajduczenia (141238)
SIEMENS Networks S.A. -
IC COM D1 R
Rua
Irm縊s Siemens, 1
Ed. 1, Piso
1
Alfragide
2720-093 Amadora
* Marek.Hajduczenia@siemens.com
http://marekhaj.easyisp.pl/index.php
(+351.21.416.7472
4+351.21.424.2082<?xml:namespace prefix = o ns =
"urn:schemas-microsoft-com:office:office"
/>
From: Ten,
Sergey Y [mailto:TenS@CORNING.COM]
Sent: quarta-feira, 3 de Janeiro de 2007
19:32
To:
STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON] [Channel link
model ad-hoc]
Marek,
The impact of the RF
overlay may be modeled (in zero approxiamtion) as increased loss at data signal
wavelength since Raman scattering will transfer energy from digital signal to
video signal.
In the next order
approximation one has to take into account transfer of the
modulation.
I can help you with
taking into account zero approximation.
SergeyFax +1 607
974 4354
-----Original
Message-----
From:
Sent: Wednesday, January 03, 2007 11:14
AM
To:
STDS-802-3-10GEPON@listserv.ieee.org
Subject: [8023-10GEPON] [Channel link model
ad-hoc]
Dear all,
since there was no activity in
the said ad-hoc for some time, I decided to run the first update of the channel
link model spreadsheet (please find it attached in a zipped form -
10GEPON-D.0.0.zip). The main changes included in this release are as follows:
- the
examined target range is always limited from L_start to Target reach, with the
granularity depending on the Target reach value. The formula used to calculate
the individual steps in column [A18:A34] is defined as follows:
=(($L$3-$L$4)/16*(ROW($A18)-ROW($A$18))+$L$4)
- the
resulting chart for power penalties versus distance has now the auto ranges
for X and Y /top value/ enabled - this way the chart auto adjusts to the
selected range
- L_step
was removed since the granularity is auto adjusted ...
- the
"Add Ins Loss" parameter is now calculated based on the split count for the
PSC module used in the EPON system. Cell L5 contains the split count
(Split_count parameter). The cell L8 value is calculated using the following
formula: =10*LOG(L5)+$AM$121*LN($L$5)+$AN$121, where the theoretical loss for
N way splitter are summed with the approximated excess loss, based on the
approximation curves estimated for typical, commercially available splitters
(Cell range [Y69:AL130]). The curve coefficients for average expected splitter
parameters are as follows: $AM$121 (A=0.5636) and $AN$121 (B=0.3979) with the
approximation curve of logarithmatic type: A*ln(N)+B
To be added, if required: changing the average
splitter type into worst/best case scenario values - preferably with the switch
variables defined in the spreadsheet (may be tough to find some space for that
though :-9)
As for the other parameters in the spreadsheet: as
Dawe suggested previously, we should probably examine the "TP4 offset cell" (T8)
which currently follows "Tx mask top" (G14) in similar style to
10GEPBud3_1_16a.xls. Dawe thinks that this cell needs a thorough review and we
should adjust its value in such a way that it compensates for the upstream
channel burst mode transmission.
Additionally, we should try to
numerate the impact of the optional video overlay channel on the overall power
budget. Is anyone willing to help me with that ?
Thank You for Your time and
attention
Best wishes
Marek
Hajduczenia (141238)
SIEMENS
Networks S.A. - IC COM D1 R
Rua
Irm縊s Siemens,
1
Ed. 1, Piso 1
Alfragide
2720-093 Amadora
* Marek.Hajduczenia@siemens.com
http://marekhaj.easyisp.pl/index.php
(+351.21.416.7472
4+351.21.424.2082