Re: [8023-10GEPON] Comment #44

[Seiji Kozaki <Kozaki.Seiji@xxxxxxxxxxxxxxxxxxxxxxxxxxx>]

Tibi-san, and all

I agree with Hamano-san's opinion.
In the meeting of Sept/2008, TF defined Rj value in UIp-p,
which is calculated by using RMS value.
Thus, the unit of specifications for Tj and Rj are should be UIp-p.

Regards,
Seiji Kozaki


Hiroshi Hamano さんは書きました:
> Dear Dr. Galambos,
>
> As indicated in 3av_0809_kozaki_2.pdf, RJ numbers in the Tables are 
> not rms, but DJ aligned value to calculate TJ.  Even though RJ does 
> not have the peak-jitter nature, I still think DJ, RJ, and TJ numbers 
> should all be described in UIp-p.
>
> Best regards,
> Hiroshi Hamano
> Fujitsu Labs. Ltd.
>
> %% Tibi Galambos <Tibi_Galambos@xxxxxxxxxxxxxx>
> %% [8023-10GEPON] Comment #44
> %% Sun, 7 Jun 2009 09:49:52 +0300
>
>   
> > 	The proposal for comment #44 is to remove "p-p" from the headers
> > of tables 75C-1 and 75C-2 altogether. This is not correct.
> >
> > 	The "p-p" attribute has to be removed from the TJ and RJ columns
> > only. The headers of both tables have to look as follows:
> > 	
> > Reference point	DJ (UI p-p)	RJ (UI )	TJ (UI )	
> >
> > 				
> > 	Justification:
> >
> > 	The jitter budget is built upon the following assumptions:
> > a.	Jitter is represented assuming the DJ to have an equi-probable
> > bimodal distribution and RJ to be Gausian.
> > b.	All sources of random jitter are assumed independent therefore
> > RJ rms values can be added by squares.
> > c.	All sources of DJ are assumed to be correlated (this is a worst
> > case assumption, meaning that all DJ components will be either together
> > at max value or together at min value, with equal probability for the
> > min and the max to occur)
> > 	Under these assumptions, RJ and TJ are defined @ BER while DJ is
> > defined by it's peak to peak value and then the following calculation
> > holds:
> > 			TJ (@ BER) = DJ p-p + RJ (@ BER)
> >
> >
> >
> >
> > Tibi Galambos 
> > Principal Engineer AFE (Analog Front-End)
> > FTTH BU
> > PMC-Sierra
> > Tel: +972-9-9628000 Ext. 473
> > Email: tibi_galambos@xxxxxxxxxxxxxx
> > <mailto:itibi_galambos@xxxxxxxxxxxxxx>
> >     
>
> ---
> -----------------------------------------
> Hiroshi Hamano
> Network Systems Labs., Fujitsu Labs. Ltd.
> Phone:+81-44-754-2641 Fax.+81-44-754-2640
> E-mail:hamano.hiroshi@xxxxxxxxxxxxxx
> -----------------------------------------
>