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Re: [10GBT] Transmit power levels



Joseph,

Thanks. Since that is from a while ago, I will wait to see what the
latest position is and George has said he will provide it.

Regards,

Sanjay

sanjay@teranetics.com
cell (650) 704-7686
office (408) 653-2235

-----Original Message-----
From: stds-802-3-10gbt@IEEE.ORG [mailto:stds-802-3-10gbt@IEEE.ORG] On
Behalf Of Joseph Babanezhad
Sent: Thursday, May 13, 2004 2:43 PM
To: STDS-802-3-10GBT@LISTSERV.IEEE.ORG
Subject: Re: [10GBT] Transmit power levels

Sanjay,

According to Solarflare's Nov. 2002 tutorial presentation (pg.17) their
proposed launch power is 10-12dBm. During his Jan. 2003 presentation

http://www.ieee802.org/3/10GBT/public/jan03/jones_1_0103.pdf

Bill Jones mentions 9.5 dBm launch power (pg.5). After Jan. 2003 meeting
Bill sent the following e-mail to the reflector and provided detailed
analysis for coming up with their peak-to-peak launch voltage. That is
where I got the 3.134Vpp launch voltage number for Solarflare.

Joseph N. Babanezhad
Plato Labs.
////////////////////////////////////////////////////////////////////////
////
/////////////////////////////////////////////////////
      Date: Mon, 13 Jan 2003 14:13:18 -0800
      From: "William Jones" <wjones@solarflare.com>
      To: <stds-802-3-10gbt@ieee.org>
      Subject: [10GBASE-T] clarification on voltage level    All headers

      In response to some questions at last weeks meeting (and to
stimulate some reflector activity), I wanted to clarify the launch
voltage level

      For 10 dBm, ideal PAM10 (random data and PSD ~sinc^2) and 100 ohm
load

      Vrms = sqrt(P*R) = 1 V

      Vpeak = Vrms*sqrt(3*(M-1)/(M+1))  where M is the number of PAM
levels
               = 1.57 V

      Vpp = 2*Vpeak = 3.13 V

      For 9.5 dBm

      Vrms = .944 V

      Vpeak = 1.48 V

      Vpp = 2.96 V

      Note: this is based on an ideal PAM signal, any filtering in the
transmit path will change the PAR and peak voltages.

      regards
      Bill

      William W. Jones, Ph.D.
      Director of Systems Engineering
      SolarFlare Communications, Inc.
      949-581-6830, ext. 2550
      mobile: 619-405-2445
      fax: 949-581-4695
      wjones@solarflare.com


////////////////////////////////////////////////////////////////////////
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----- Original Message -----
From: "Sanjay Kasturia" <SKasturia@TERANETICS.COM>
To: <STDS-802-3-10GBT@listserv.ieee.org>
Sent: Thursday, May 13, 2004 2:08 PM
Subject: [SPAM] Re: [10GBT] Transmit power levels


> George,
>
> Thanks.
>
> Sanjay
>
> sanjay@teranetics.com
> cell (650) 704-7686
> office (408) 653-2235
>
> -----Original Message-----
> From: stds-802-3-10gbt@IEEE.ORG [mailto:stds-802-3-10gbt@IEEE.ORG] On
> Behalf Of George A. Zimmerman
> Sent: Thursday, May 13, 2004 2:07 PM
> To: STDS-802-3-10GBT@LISTSERV.IEEE.ORG
> Subject: Re: [10GBT] Transmit power levels
>
> No , at the time of Joseph's presentation we noted it was  not
correct.
> I can't answer  in  detail now (I'm on my mobile ), but we will at the

> meeting or before.
>
> George A. Zimmerman
> cell: 310 920 3860
> (sent from my mobile)
>
> -----Original Message-----
>     From: "Sanjay Kasturia"<SKasturia@TERANETICS.COM>
>     Sent: 5/13/04 1:46:33 PM
>     To:
>
"STDS-802-3-10GBT@LISTSERV.IEEE.ORG"<STDS-802-3-10GBT@LISTSERV.IEEE.ORG>
>     Subject: [10GBT] Transmit power levels
>       A quick scan through past presentations reveals a few different
>     proposals for transmit power levels.
>
>     http://www.ieee802.org/3/10GBT/public/mar03/babanezhad_1_0303.pdf
> , a
>     March 2003 presentation by Joseph Babanezhad of Plato Labs,
> proposes 2v
>     peak to peak and also has a table on slide 16 that lists other
prior
>     proposals: 2v peak to peak from a proposal from Cicada and 3.134v
> peak
>     to peak for a proposal from Solarflare.
>
>     A subsequent presentation from George Zimmerman of Solarflare,
> gives a
>     range of  TX power, > 6dBm to <10dBm though there is no mention of
>     actual peak to peak voltages. If I assume that the 3.134v peak to
> peak
>     corresponds to 10dBm then the 6dBm number will be about 2v peak to

> peak.
>
>     Joseph, Vivek (Cicada) and George - is my interpretation of each
> of your
>     proposals correct? Were there any other proposals on transmit
power?
>
>     Thanks,
>
>
>     Sanjay
>
>     sanjay@teranetics.com
>     cell (650) 704-7686
>     office (408) 653-2235
>