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Re: [8023-10GEPON] Downstream wavelength review



Dear Frank,

Thank you for your response and proposal.
It is only my concern.

I think it depends on the decision of the power budget plan because:
-If we use a PIN-PD for a PX/20 ONU receiver, I think an OLT transmitter 
will need cooled system because of its high out-put power more than 5 dBm.
-Moreover, if we use an APD for PX30 and a PIN-PD for PX10, each OLT has 
almost the same output power range.
So I thought the full wavelength window for PX10/20 was a good 
compromise to eliminate the dependency on the power budget plan.

But, I feel your additional compromise is good for me as well.

Best regards,
Ken-Ichi

At 2007/08/31 0:16 Frank Effenberger wrote:
> Dear Ken-Ichi, 
> 
> I have a question about your idea:  Why would somebody want to make an OLT that supports PX10-20-30?  
> 
> The whole point of making a PX10 or PX20 is to make a cheaper OLT.  If you make an OLT that supports PX30, you will have already spent the extra cost to make the high-power OLT...  You don't gain anything to down grade it.  
> 
> If you are thinking about just being able to say, "My OLT complies with PX10/20/30 optical specs,"  well, I doubt you will ever be able to do that.  We haven't finalized the entire power budget yet, but it seems that in most proposals the PX10/20 are considerably lower in power.  Are you going to try to implement power control?  That's more cost, to make an OLT that does less! 
> I don't think it is an attractive feature.  
> 
> Marek correctly pointed out that the use of a band from 1580 to 1600 is very attractive for the reason that it coincides with the CWDM band plan.  I worry that if we define the PX10 and PX20 band to be the 'odd' 1574 to 1600nm, then it confuses the issue.  
> 
> Toward a compromise, would you accept a situation where we specify the PX10 and PX20 Tx bands to be 1580 to 1600nm, but we add a note like: 
> 
> Note: Deviations of the PX10 and PX20 Tx wavelength down to 1574nm are permissible.  
> 
> 
> You may think this sounds strange, but I really think it adds value, in that the nominal wavelengths remain the 'normal sounding' 1580 to 1600 values, yet it gives you the latitude that you want.  
> 
> How about that? 
> 
> Sincerely,
> Frank E.
> 
> 
> 
> 
> -----Original Message-----
> From: Ken-Ichi Suzuki [mailto:kenyichi@ansl.ntt.co.jp] 
> Sent: Thursday, August 30, 2007 4:37 AM
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: Re: [8023-10GEPON] Downstream wavelength review
> 
> Dear Marek and all,
> 
> Thank you for your answer.
> So I believe we should not limit the wavelength range of PX10/20
> transmitters considering both the use of CWDM grid and compatibility
> to PX30 cooled-lasers, if there are no reasons for that limitation.
> 
> Best regards,
> Ken-Ichi
> 
> At 2007/08/30 17:23 Hajduczenia, Marek wrote:
>> Dear Otaka-san, 
>> >From what I gather from the presentations provided so far, the OLT transmitters required for PR30 systems have different requirements than PR10/PR20 ones - for once, they require (most likely) cooling which is not required (at least that is what I gather) for PR10s and PR20s. I would like to learn the opinions of components vendors - they are more likely to be familiar with market availability of 1580 - 1600 nm devices meeting PR10/20 requirements. 
>> Please note also that the ONU receiver remains a universal device, with the sensitivity window spanning between 1574 and 1600 nm, thus covering both PR10/20 and PR30 devices on the other end of the link. The only differentation here would be the OLT transmitter, nothing else. 
>> Any other comments ? 
>> Thank You for Your feedback 
>>
>> Marek Hajduczenia (141238)
>> NOKIA SIEMENS Networks S.A., Portugal - R
>> Rua Irmãos Siemens, 1
>> Ed. 1, Piso 1
>> Alfragide
>> 2720-093 Amadora
>> Portugal
>> * Marek.Hajduczenia@siemens.com
>> http://www.marekhajduczenia.info/index.php
>> (+351.21.416.7472  4+351.21.424.2082
>> "C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg." - Bjarne Stroustrup 
>>
>> -----Original Message-----
>> From: Akihiro Otaka [mailto:ootaka@ansl.ntt.co.jp] 
>> Sent: quinta-feira, 30 de Agosto de 2007 9:18
>> To: Hajduczenia, Marek; STDS-802-3-10GEPON@listserv.ieee.org
>> Subject: Re: [8023-10GEPON] Downstream wavelength review
>>
>> Dear Marek and all.
>>
>> Thank you for your prompt comment.
>> This is Akihiro Otaka.
>>
>> I think if there are someone who try to realize B++ and PX20/10
>> OLT with identical device (it may be a cooled device), the superset
>> band idea is better for them.
>>
>> Are there no such requirement in practice?
>>
>> Best regards,
>> Akihiro Otaka
>>
>>
>> At 16:18 07/08/30, Hajduczenia, Marek wrote:
>>  >Dear Suzuki-san,
>>  >
>>  >I believe I may answer this question since Frank is probably still at night
>>  >time (Frank, please confirm if I what I am saying is OK) ...
>>  >The main reason why Frank proposes to have PR10/PR20 PMDs use the 1580 -
>>  >1600 nm window in the downstream is the compatibility with the CDWM
>>  >wavelength grid and the availability of uncooled transmitters centered
>>  >around 1590 nm with the power putput sufficient to cope with these
>>  >particular power budgets. You are right that it does little harm to expand
>>  >the band to 1574 - 1600 though the big question is whether it will be used
>>  >in practice. I do not see a reason to block part of the band which will not
>>  >be used by the PMDs anyway.
>>  >
>>  >Hope that answers Your question
>>  >
>>  >Marek Hajduczenia (141238)
>>  >NOKIA SIEMENS Networks S.A., Portugal - R
>>  >Rua Irmテ」os Siemens, 1
>>  >Ed. 1, Piso 1
>>  >Alfragide
>>  >2720-093 Amadora
>>  >Portugal
>>  >* Marek.Hajduczenia@siemens.com
>>  >http://www.marekhajduczenia.info/index.php
>>  >(+351.21.416.7472  4+351.21.424.2082
>>  >"C makes it easy to shoot yourself in the foot; C++ makes it harder, but
>>  >when you do, it blows away your whole leg." - Bjarne Stroustrup
>>  >
>>  >-----Original Message-----
>>  >From: Ken-Ichi Suzuki [mailto:kenyichi@ansl.ntt.co.jp]
>>  >Sent: quinta-feira, 30 de Agosto de 2007 8:00
>>  >To: STDS-802-3-10GEPON@listserv.ieee.org
>>  >Subject: Re: [8023-10GEPON] Downstream wavelength review
>>  >
>>  >Dear Frank
>>  >
>>  >Thank you for your proposal.
>>  >Basically, I agree to your proposal.
>>  >But I have a comment on Option D.
>>  >
>>  >I believe the full wavelength range of 1574 to 1600 nm can be used
>>  >for PX10 and PX20 in Option D.
>>  >If someone wants to use the range of 1574 to 1580 for PX10 and PX20
>>  >as well as the range of 1580 to 1600 nm, I think we should not limit
>>  >the wavelength range of Option D.
>>  >
>>  >So I would like to confirm whether we should limit the wavelength
>>  >range because I believe that the specifications should be accepted
>>  >by as many people as possible (although I do not have a strong
>>  >opinion to PX10 and PX20).
>>  >
>>  >Best regards,
>>  >Ken-Ichi
>>  >
>>  >At 2007/08/29 0:07 Frank Effenberger wrote:
>>  >> Dear All,
>>  >>
>>  >>
>>  >>
>>  >> I have put together some slides that review the downstream wavelength issue,
>>  >> and put forward a solution that I think may have some common support.
>>  >>
>>  >>
>>  >>
>>  >> Please give me your comments, and if you would like to support it, let me
>>  >> know that, also.
>>  >> 
>>
>>
>>
> 
> 


-- 
Ken-Ichi Suzuki
NTT Access Network Service Systems Labs.
E-mail:kenyichi@ansl.ntt.co.jp
Tel:+81-43-211-3189/Fax:+81-43-211-8250