Dear all,
I would like to start discussion on the
issues related with Task 3 of our ad hoc. I am interested mainly in the
following information.
- What kind of sensitivity can we expect from commercially available 10G PIN diodes. I saw figures in the presentations given in the 10GEPON TF ranging from -14 to -18, which makes me wonder where the truth lies. This is a very important factor since it impacts our overall link budget in the downstream channel. Are we likely to operate closer to -14 with standard devices rather than -18 ? Does anybody have any experience with that that they could share with us?
- What about development/research in terms of PIN diodes for 10G systems ? In 2-3 years, when the standard is accepted, there may be some progress in terms of low cost PIN diodes for 10G systems. Is anybody aware of such development?
- Are -16/-18 PIN diodes for ONUs economically feasible, meaning - are they sufficiently mature and is there sufficient production capacity to assure reasonable cost? I am asking this because perhaps it is less expensive to use a port-amplifiers at the OLT side and increase the launch power rather than invest into higher sensitivity detectors on the ONU side, while ONU module price should be kept as low as possible?
- What about low grade APDs for ONUs ? Any ideas regarding the price comparison for low grade APD versus good quality PIN ? Where is the trade-off point?
- Regarding the OLT RX modules - there is little doubt that we need an APD. What sensitivities can we obtain with good quality APDs in the burst mode ? What kind of burst mode penalty do we observe in the upstream channel at 10 G ? Does anybody have any reasonable data on that ?
- Again, what about progress in terms of APD diode sensitivity ? I heard about some research going on in terms of QD (Quantum Dots) APDs, though it is considered still largely immature and probably it will not become commercially available within the next 2-3 years. I may be mistaken here. Does anybody have any more precise information on this topic ?
- The issue of transmitters for OLT and ONU. In the OLT we will probably need to have an externally modulated laser, possibility with a post-amplifier if we want to have increased split ratio at standard transmission distances. What kind of amplification technologies do You see as viable for 10GEPON systems ? EDFA's may proove too expensive, Raman amplifiers are bulky so we are generally left with SOAs, unless I missed something. Does anybody have any data / presentation / would like to prepare a short review of the existing amplification techniques and laser sources for the OLT side ?
- The same goes for the ONU side - we need to know what type of lasers we can use in the ONU in the light of the increased loss budget of >= 29 dB for high split ratios and standard 10/20 km transmission reach. Are we limited to ONU side amplifiers or should we rather concentrate on the OLT side preamplifier ? What is Your opinion ?
I would appreciate some discussion on these
topics, especially from manufacturers of RX/TX equipment. Please avoid corporate
pitches if possible. Thank You
Best wishes
Marek
Hajduczenia (141238)
(PhD
Student - COM RD1)
SIEMENS Networks S.A. - IC
Rua
Irmãos Siemens, 1
Ed. 1, Piso 1
Alfragide
2720-093
Amadora
Portugal
*
Marek.Hajduczenia@siemens.com
http://marekhaj.easyisp.pl/index.php
(+351.21.416.7472 4+351.21.424.2082
