Re: [8023-10GEPON] [Channel link model ad-hoc]

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Marek,

The impact of the RF overlay may be modeled (in zero approxiamtion) as increased loss at data signal wavelength since Raman scattering will transfer energy from digital signal to video signal.

In the next order approximation one has to take into account transfer of the modulation.

I can help you with taking into account zero approximation.

SergeyFax +1 607 974 4354

-----Original Message-----
From: Hajduczenia, Marek [mailto:marek.hajduczenia@SIEMENS.COM]
Sent: Wednesday, January 03, 2007 11:14 AM
To: STDS-802-3-10GEPON@listserv.ieee.org
Subject: [8023-10GEPON] [Channel link model ad-hoc]

Dear all,

since there was no activity in the said ad-hoc for some time, I decided to run the first update of the channel link model spreadsheet (please find it attached in a zipped form - 10GEPON-D.0.0.zip). The main changes included in this release are as follows:

the examined target range is always limited from L_start to Target reach, with the granularity depending on the Target reach value. The formula used to calculate the individual steps in column [A18:A34] is defined as follows: =(($L$3-$L$4)/16*(ROW($A18)-ROW($A$18))+$L$4)
the resulting chart for power penalties versus distance has now the auto ranges for X and Y /top value/ enabled - this way the chart auto adjusts to the selected range
L_step was removed since the granularity is auto adjusted ...
the "Add Ins Loss" parameter is now calculated based on the split count for the PSC module used in the EPON system. Cell L5 contains the split count (Split_count parameter). The cell L8 value is calculated using the following formula: =10*LOG(L5)+$AM$121*LN($L$5)+$AN$121, where the theoretical loss for N way splitter are summed with the approximated excess loss, based on the approximation curves estimated for typical, commercially available splitters (Cell range [Y69:AL130]). The curve coefficients for average expected splitter parameters are as follows: $AM$121 (A=0.5636) and $AN$121 (B=0.3979) with the approximation curve of logarithmatic type: A*ln(N)+B

To be added, if required: changing the average splitter type into worst/best case scenario values - preferably with the switch variables defined in the spreadsheet (may be tough to find some space for that though :-9)

As for the other parameters in the spreadsheet: as Dawe suggested previously, we should probably examine the "TP4 offset cell" (T8) which currently follows "Tx mask top" (G14) in similar style to 10GEPBud3_1_16a.xls. Dawe thinks that this cell needs a thorough review and we should adjust its value in such a way that it compensates for the upstream channel burst mode transmission.

Additionally, we should try to numerate the impact of the optional video overlay channel on the overall power budget. Is anyone willing to help me with that ?

Thank You for Your time and attention

Best wishes

Marek Hajduczenia (141238)
SIEMENS Networks S.A. - IC COM D1 R
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