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What
we are calculating is the S/N of a signal with relative noise, i.e. different
amounts on each level, with a PP of 0.9dB. The TP3 compliance signal will
then simulate this relative noise with equal noise on each level yielding the
same S/N.
Also,
doesn't the simple formula still need to take into account the extinction
ratio?
In any
case, you are probably right that the approximation of equal power is
fine.
Lew
-----Original Message-----
From:
Tom Lindsay [mailto:tlindsay@IEEE.ORG]
Sent: Wednesday, October 27,
2004 3:22 PM
To:
STDS-802-3-10GMMF@listserv.ieee.org
Subject: Re: [10GMMF] TP3
calculation of OSNR for compliance test
Lew -
Your development assumes that the rms value due to RIN is
proportional to the optical signal power. In the case of TP3 testing, we plan
on adding a white noise generator before the E/O, such that its rms noise is ~
the same at both levels.
In this case, the math can get much simpler and should revert to the
simple textbook formula PP(dB)=-5*log[1-(Q/Qn)^2], and Qn
=Q/sqrt(1-10^(PP(dB)/-5)).
For 0.9 dB, Qn=12.1. (Compare to your equation (8)).
Comments?
Tom
----- Original Message -----
Sent: Tuesday, October 26, 2004 8:45
AM
Subject: [10GMMF] TP3 calculation of
OSNR for compliance test
Sorry for the late e-mail, my first attempt got bounced as
too large a file size.
Please find attached a calculation I have done
for the optical S/N we need to have on the TP3 compliance signal. It
also has some calculations of the resulting EDC S/N for different receive
powers and receiver front end sensitivities.
Lew
-----Original
Message-----
From: Michael Lawton
[mailto:mike_lawton@AGILENT.COM]
Sent: Tuesday, October 26, 2004 2:22
AM
To: STDS-802-3-10GMMF@listserv.ieee.org
Subject:
[10GMMF] TP3 meeting Agenda + dial in Oct 26
Dear
TP3'ers,
Here is the agenda for today's meeting:-
Tuesday
October 26th 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. Agenda
additions/changes?
4. Static
Channel
Methodology
- Noise loading - review calculations from
Lew
- Channel types and exact
characteristics
o review comments from Tom reference rise and fall
time
5.
Jitter
- Petre kindly agreed to evaluate jitter testing requirements and the need
for a high
frequency
sinusoidal
interferer
6. Link
Budget
- I think we have agreed that the testing is designed to emulate the
budget
- Do we need to do more work on the
budget?
- Is our thinking on metrics changing? (PIE-L, PIE-D, fixed length
equalisers)
- 300m question
7.
OMA Measurement
methodology
- Piers is exploring a histogram vs a slow pattern approach.
I'm not
expecting we work through all the items ... however I want to keep them on
the agenda so we understand our work list and where it makes sense we can
shift around the order.
Talk to you all later.
Best
Regards
MIke
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