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AW: AW: [802.3ae_Serial] budget for 1310 (wrong intitial subject)




Sorry ,I had the wrong subject in the previous Mail.
Regards
> ----------
> Von: 	Rahn, Juergen (Juergen)
> Gesendet: 	Dienstag, 3. Juli 2001 13:56
> An: 	'DAWE,PIERS (A-England,ex1)'
> Cc: 	stds-802-3-hssg-serialpmd@xxxxxxxx
> Betreff: 	AW: AW: [802.3ae_Serial] Issue with 1500 Power
> 
> 
> Hi,
> OK if I make the same thing on 1310nm , use the eye penalty at receiver in
> the same
> way , however due to the direct values in triple tradeoff I have to
> consider
> path penalty (I took 1 dB) I end up with the following figures:
> __________________________________________________________________________
> __
> ________________________
> 13100nm
> __________________________________________________________________________
> __
> ________________________			
> transmitter OMA min					-4,6	dBm
> (lowest value from table)
> __________________________________________________________________________
> __
> _________________________
> receiver sensitivity (OMA)		-10,68	dBm	
>  + receiver test signal penalty		  1,78	dB	
> Total )penalty free signal) sensitivity (OMA)		-12,46	dBm	
> 
> __________________________________________________________________________
> __
> __________________________			
> attenuation budget					7,86	dB
> 7,04dB defined
> The sensitivity results in:
> This gives in average power, ideal ER:	-15,46	dBm	
> and at 4 dB ER				-11,96	dBm	
>  +power penalty				-12,96	dBm	ITU style
> sensitivity
> 
> This is 2 dB more stringent than ITU.
> Again we do not see such unit s on the market.
> Regards Juergen
> 
> 
> > ----------
> > Von: 	DAWE,PIERS (A-England,ex1)[SMTP:piers_dawe@xxxxxxxxxxx]
> > Gesendet: 	Dienstag, 3. Juli 2001 13:17
> > An: 	Rahn, Juergen (Juergen)
> > Cc: 	stds-802-3-hssg-serialpmd@xxxxxxxx
> > Betreff: 	RE: AW: [802.3ae_Serial] Issue with 1500 Power
> > 
> > Juergen,
> > 
> > You are less confused than you say!  I have compared my understanding
> with
> > yours: see below.  There are some editorial/clarity issues and one
> > outstanding point which is: is the 802.3ae D3.1 ER/EW receive
> sensitivity
> > very demanding or expensive?
> > 
> > Piers
> > 
> > > -----Original Message-----
> > > From: Rahn, Juergen (Juergen) [mailto:krahn@xxxxxxxxxx]
> > > Sent: 03 July 2001 09:01
> > > To: 'Mike Dudek'
> > > Cc: stds-802-3-hssg-serialpmd@xxxxxxxx; 'Ron Miller'
> > > Subject: AW: AW: [802.3ae_Serial] Issue with 1500 Power
> > > 
> > > 
> > > Sorry,
> > >  I am still confused.
> > > You talk about ISI penalty now but this is stated at transmitter power
> > > anyway and not quantified. 
> > > In the table it reads:
> > > Launch power (min) in OMA minus TDP * -1.39 dBm
> > > with a note:
> > > * TDP is transmitter and dispersion penalty
> > > up to now I interpreted that we have to consider the 
> > > penalties and than
> > > compensate the penalties by increasing the power (Whatever 
> > > the penalties
> > > are) First question is this a correct understanding?
> > 
> > Yes
> > 
> > > If yes you will not have any advantage at the receiver when 
> > > increasing the
> > > power by the amount of penalty as a penalty represents the decrease in
> > > sensitivity, so this should add up to zero.
> > 
> > Yes
> > 
> > > (It comes to my mind that the - in this parameter suggests 
> > > that the power
> > > may be decreased by the penalties which would give trouble 
> > > but this may be a
> > > short editorial discussion)
> > 
> > Juergen please make a comment.  Editor please note!
> >  
> > > If this understanding is correct let me make the calculation:
> > > Simple case ideal transmitter no penalties :
> > > Launch power (min) in OMA minus TDP * 		-1.39 dBm
> > > 
> > > Stressed receive sensitivity (max) in OMA ?, ? , §		
> > >  (-11.40)
> > > (dBm)
> > > 
> > > I calculate an attenuation budget of about 10 dB out of this not 13db.
> > 
> > No, you have it right below.
> > 
> > > However there is a term in the receiver table  .
> > > ( I interpret max sensitivity here also as a minimum 
> > > requirement, I don not
> > > hope that this means the sensitivity should not be better 
> > > than this value,
> > > but this may be an editorial problem)
> > 
> > Maximum is more dBm, representing worst case for a receiver sensitivity,
> > so
> > I think this one is the right way round.  Please make a comment if any
> > doubt
> > remains.
> > 
> > > Vertical eye closure penalty ** (max) 3.0 dB
> > > with a note
> > > **Vertical eye closure penalty is a test condition for 
> > > measuring stressed
> > > receive sensitivity. It is not a required charac-teristic
> > > of the receiver.
> > > This note is a bit misleading for me, however I interpret 
> > > this note in the
> > > way that when measuring stressed sensitivity there has to be 
> > > used a signal
> > > that has 3 dB penalty, what means that for a signal that does 
> > > not show this
> > > penalty  ( as assumed at the transmitter in this 
> > > consideration)  we can add
> > > this to the sensitivity. Is this the ISI penalty you mention? 
> > > In this case
> > > we really at the end coming out with 13 dB budget.
> > > Calculation would look like:
> > > _________________________________________________________
> > > transmitter OMA min	 				  -1.39	dBm
> > > _________________________________________________________
> > > receiver sensitivity (OMA)		 -11.40	dBm
> > >  + receiver test signal penalty	           	    3.0	dB
> > > _____________________________________________
> > > Total )penalty free signal) sensitivity in OMA		
> > >  -14.4	dBm
> > > __________________________________________________________
> > > attenuation budget	   				   
> > > 13.01	dB
> > > 
> > > So can you confirm this understanding ?
> > 
> > Yes.
> > 
> > > If not would it be possible to set up a similar calculation 
> > > like this and
> > > clarify.
> > > 
> > > If this understanding is correct than we have 14.4 dBm sensitivity
> > > requirement in OMA and this for instance get it comparable to 
> > > transponders
> > > you can by translates (being optimistic into average power 
> > > sensitivity of :
> > > - 14.4 dBm OMA will give -17.4 dBm ideal ER sensitivity or 
> > > -16 dBm (average
> > > power sensitivity) at ER of 8.2 dB as used in ITU. This is 2 
> > > dB harder as
> > > ITU and represents the BOL typical value that you get  for 
> > > such components.
> > > For an interface spec we however require EOL worst case!
> > > For my understanding this is not realistic today and if done will be
> > > expensive.
> > 
> > Is it relevant to point out that SONET receiver sensitivities are
> > standardised for a "worst" Tx eye which has the same 3 dB penalty?  Not
> > sure
> > if you have already taken that into account.
> >  
> > > Regards Juergen Rahn
> > > 
> > > 
> > > > ----------
> > > > Von: 	Mike Dudek[SMTP:mdudek@xxxxxxxxxxxx]
> > > > Gesendet: 	Dienstag, 3. Juli 2001 03:02
> > > > An: 	Rahn, Juergen (Juergen)
> > > > Cc: 	stds-802-3-hssg-serialpmd@xxxxxxxx; 'Ron Miller'
> > > > Betreff: 	Re: AW: [802.3ae_Serial] Issue with 1500 Power
> > > > 
> > > > 
> > > > A further attempt to clarify this.
> > > > The 3dB difference is the ISI penalty that is imposed when 
> > > performing the
> > > > stressed receiver sensitivity test which corresponds to the 
> > > maximum value
> > > > of the
> > > > Transmitter and Dispersion Penalty of the Transmitter.  If one has a
> > > > transmitter
> > > > that produces this amount of penalty then one has to 
> > > increase the output
> > > > power
> > > > by 3dB.  Hence the 13dB is attained.
> > > > Regards Mike
> > > > 
> > > > "Rahn, Juergen (Juergen)" wrote:
> > > > 
> > > > > Hi
> > > > > The difference between current defined sensitivity and 
> > > what would be
> > > > > required (straightforward without any additional margin 
> > > penalty....) is
> > > > 3
> > > > > dB, what means the attenuation budget would be 10 dB.
> > > > > Does this clarify?
> > > > > Regards Juergen
> > > > >
> > > > > > ----------
> > > > > > Von:  Ron Miller[SMTP:rmiller@xxxxxxxxxxx]
> > > > > > Gesendet:     Mittwoch, 27. Juni 2001 18:10
> > > > > > An:   Rahn, Juergen (Juergen); 
> > > stds-802-3-hssg-serialpmd@xxxxxxxx
> > > > > > Betreff:      RE: [802.3ae_Serial] Issue with 1500 Power
> > > > > >
> > > > > >
> > > > > > juergen
> > > > > >
> > > > > > Please check your numbers below.  Thanks
> > > > > >
> > > > > > Ron Miller
> > > > > >
> > > > > > -----Original Message-----
> > > > > > From: Rahn, Juergen (Juergen) [mailto:krahn@xxxxxxxxxx]
> > > > > > Sent: Wednesday, June 27, 2001 3:30 AM
> > > > > > To: stds-802-3-hssg-serialpmd@xxxxxxxx
> > > > > > Subject: AW: [802.3ae_Serial] Issue with 1500 Power
> > > > > >
> > > > > >
> > > > > >
> > > > > > Hi,
> > > > > > as discussed in the PMD call I understand there is a 
> > > mismatch in the
> > > > > > values
> > > > > > defined for the 1550 case. The minimum transmitter OMA 
> > > is  -1.39dBm +
> > > > > > penalties. Link attenuation is set to 13 dB , so this 
> > > would give a
> > > > > > sensitivity requirement of -14,39 dBm OMA ,. however 
> > > the stressed
> > > > > > sensitivity (In OMA) is defined to be -11.4 dBm.
> > > > > >
> > > > > >  so there are 10 dB
> > > > > > difference between those two values.
> > > > > >
> > > > > > LOOKS MORE LIKE ABUT 3 DB TO ME.
> > > > > >
> > > > > > The trade off that has been introduced
> > > > > > (that I do not like, but this is a different 
> > > discussion) will shift
> > > > this
> > > > > > complete link power level. When comparing this with powers and
> > > > > > sensitivities
> > > > > > as defined in ITU the following appears: ITU defines 2 
> > > dB path penalty
> > > > > > with
> > > > > > this OMA we would end at a minimum transmitter power average of
> > > > about -
> > > > > > 1
> > > > > > dBm which is in line to ITU. with 109 dB attenuation 
> > > there is margin
> > > > in
> > > > > > the
> > > > > > ITU numbers, with 11 dB and ITU sensitivity (Which has 
> > > been confirmed
> > > > by
> > > > > > measurements) we add up to 0. ( -14 dBm average power 
> > > sensitivity and
> > > > 2 dB
> > > > > > penalty gives us the G.691 application). When simply taking this
> > > > > > transmitter
> > > > > > power and 13 dB attenuation we end up with 2 dB better 
> > > sensitivity
> > > > > > requirement as currently experienced by measurements 
> > > (worst case EOL).
> > > > > > This may start this conversation.
> > > > > > Regards Juergen
> > > > > >
> > > > > >
> > > > 
> > > 
> > 
>