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@brocade.com]
> > Gesendet: Mittwoch, 27. Juni 2001 18:10
> > An: Rahn, Juergen (Juergen); stds-802-3-hssg-serialpmd@ieee.org
> > 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@lucent.com]
> > Sent: Wednesday, June 27, 2001 3:30 AM
> > To: stds-802-3-hssg-serialpmd@ieee.org
> > 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
> >
> >