Re: [8023-10GEPON] PIN-PD Power Budget
Dear Sirs,
Thank you for discussing the power budget table in 3av_0705_takizawa_1.pdf.
For your interest, I copied again the E-mail discussion with Dr.Effenberger
below.
You can also find it in the E-mail reflector archive.
http://www.ieee802.org/3/10GEPON_study/email/msg00644.html
Best regards,
Hiroshi Hamano
------- Forwarded Message
%% Hiroshi HAMANO <hamano.hiroshi@JP.FUJITSU.COM>
%% Re: [8023-10GEPON] [POWER BUDGET] resolving differences over PIN vs. APD
%% Tue, 10 Jul 2007 20:48:35 +0900
Dear Dr. Effenberger,
I cannot understand why you say that there exists unfairness between PIN
and APD sensitivities. I believe both the RX sensitivities are quite
fair enough with regard to production feasibility.
No such arguments arise among vendors here, because they always think
about both receiver types seriously and check both budget tables.
If the RX-type will be once decided, all the vendors have to put the one
in production anyway, even though their RX preference is the other.
If you think that PIN-RX sensitivity in our vendor summary looks conservative,
same as Dr. Frank Chang thought that APD-RX looks so --- he pointed that out
at the last Geneva meeting ---, I understand somewhat both of your feelings,
considering such a tight Class B++ power budget.
But please understand the 10G transceiver production facts, for instance, XFPs.
It is not the laboratory experiments or single ROSA performance.
Vendors also have to spend a lot care for product deviations, especially
for ONU, to avoid yield which makes its cost jump up.
Besides, as it is the specification of ONU sensitivity, additional unknown
WDM filter loss onto the bare transceiver cannot be ignored, which Takizawa
always comments on his power budget presentation.
I once suggested that a slight change (0.5dB) for RX sensitivity, and got
a strong booing from all the vendors.
So, the vendors cannot change their RX sensitivities of both PINs and APDs
at moment.
Best regards,
Hiroshi Hamano
---------------------
%% Bidyut Parruck <Bidyut@CORTINA-SYSTEMS.COM>
%% Re: [8023-10GEPON] PIN-PD Power Budget
%% Wed, 29 Aug 2007 16:59:41 -0700
>
>
>
> Hi Frank,
>
>
>
> Thanks for clearly stating the issue. The datasheets I'm "casually
> looking on the web" are from "major" vendors.
>
>
>
> Both examples I showed had a sensitivity of -21 dBm for BER of 1x10E-12.
> I can understand 2-3 dB of margin - our current equations are using 5
> dB. I do understand, initially, this could increase the cost of PIN-PD.
> But in the long run the same companies will innovate and bring the cost
> down. I think we should revisit this subject.
>
>
>
> Regards,
>
>
>
> Bidyut
>
>
>
> From: Frank Effenberger [mailto:feffenberger@HUAWEI.COM]
> Sent: Wednesday, August 29, 2007 4:16 PM
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: Re: [8023-10GEPON] PIN-PD Power Budget
>
>
>
> All,
>
>
>
> The 1e-12 BER PIN sensitivity that is being used in the slide below is
> -16 dBm.
>
> The slide says that the 1e-4 BER sensitivity is -19 dBm.
>
> The slide says that the 1e-3 BER sensitivity is -20 dBm.
>
>
>
> What Bidyut is noticing is that many receivers he is casually looking at
> on the web seem to have a much better sensitivity curve than what this
> slide says. The typical sensitivity numbers are -20dBm, and I'd believe
> that the 'hard spec' would be about -18 dBm. I've been saying the same
> thing for many months. But "team PIN" seems convinced on -16 dBm, for
> reasons of economy and yield, I've been told. But that is a matter of
> how aggressive you want to be with the specification....
>
>
>
> Sincerely,
>
> Frank E.
>
>
>
>
>
>
>
> ________________________________
>
> From: Bidyut Parruck [mailto:Bidyut@CORTINA-SYSTEMS.COM]
> Sent: Wednesday, August 29, 2007 6:05 PM
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: Re: [8023-10GEPON] PIN-PD Power Budget
>
>
>
> Hi Ryan,
>
>
>
> I'm not sure where the FEC numbers are baked in. Here's the slide 8 from
> 3av_0705_takizawa_1.pdf.
>
>
>
> Bidyut
>
>
>
>
>
>
>
> From: Ryan Hirth [mailto:ryan.hirth@TEKNOVUS.COM]
> Sent: Wednesday, August 29, 2007 2:10 PM
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: Re: [8023-10GEPON] PIN-PD Power Budget
>
>
>
> Bidyut,
>
> The additional gain from operating at BER 10E-12 to 10E-3 in your
> example is the FEC optical gain. You cannot increase the receiver
> sensitivity and add gain for FEC since this would be adding in the same
> gain factor twice.
>
> Regards,
>
>
>
> Ryan Hirth
>
> Director of ASIC Engineering
>
> Teknovus Inc.
>
>
>
> ________________________________
>
> From: Bidyut Parruck [mailto:Bidyut@CORTINA-SYSTEMS.COM]
> Sent: Wednesday, August 29, 2007 1:31 PM
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: [8023-10GEPON] PIN-PD Power Budget
>
>
>
> I have been looking at publicly available 10Gbps PON photodiode
> datasheets from major suppliers. For the receiver sensitivity, they all
> claim -21 dBm for BER of 1x10E-12. The typical characteristics curve
> suggests a BER of 1x10E-3 for input power level of -25 dBm.
>
>
>
> With input BER of 1x10E-3, we can find FEC algorithms which would
> provide output BER of 1x10E-12 or better. Excuse my ignorance of the
> subject, but why can't we use -24 dBm as the receiver sensitivity for
> PIN-PD receivers? That will give us an additional 4 dB.
>
>
>
> Here are some examples:
>
>
---
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HIROSHI HAMANO Network Systems Labs.
FUJITSU Labs. Ltd., Kawasaki, 211-8588 JAPAN
TEL: +81-44-754-2641 FAX: +81-44-754-2640
E-mail: hhlsi@flab.fujitsu.co.jp
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