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All I’m working on it and reviewing what should be more important ones tied to how OFDM may in fact work in an HFC network. So far the basis for the parameters centers around 3 areas and distinct network models: Overlay: The key elements for overlay are some of what you have indicated below plus the RF side of the node parameters which would also include: (the assumption is this is standalone optical to RF amplifier coupled into a section of RF plant which maybe after some type of cascade) 1. Symbol rate and power per Hertz for desired normal operation 2. Effective RF channel width for desired capacity a. RF band usage needs, requirements and capacity definitions in specified bandwidths at normal and points of limited operation 3. Effects of positive and negative tilt 4. Cable attenuation 5. Cable impedance and passive mismatch viewed as reflections 6. Distortions – this should be low for a single RF drive amplifier at the optical to RF transition for EPoC however the overlay section will be impacted by all other devices a. CIN in the overlay will be affected by the existing plant lasers and any cascade of HFC RF amplifiers. b. CTB in the overlay as above c. CSO in the overlay as above 7. Group delay 8. Ingress from non-authorized and authorized sources for forward plant and forward plant as a return plant in the TDD environment a. Impact by micro reflection, passive network performance as a result of residential subscribers actions 9. RF requirements for EPoC a. Transmission levels for acceptable operations and co-existence of residential scribers b. Receive level requirements c. Filtering and protection requirement to protect co-existent services \ 10. Filtering requirements at a point outside any physical equipment. Node + “X”: the key elements for this scenario are mostly the same as the above but where the EPoC signal is implemented into the existing laser system at the head end or distribution hub and sent to an existing fiber node just as the residential HFC network does today. In this case the predominant operational and distortion impact is in the optical transport and must be factored into the RF portion of the network whether in the N+”x” configuration or the corner case where one leg out of a node may be where the EPoC signal is deployed. 1. Symbol rate and power per Hertz for desired normal operation 2. Effective RF channel width for desired capacity a. RF band usage needs, requirements and capacity definitions in specified bandwidths at normal and points of limited operation 3. Effects of positive and negative tilt 4. Cable attenuation 5. Cable impedance and passive mismatch viewed as reflections 6. Distortions – this should be low for a single RF drive amplifier at the optical to RF transition for EPoC however the overlay section will be impacted by all other devices a. CIN in the overlay will be affected by the existing plant lasers and any cascade of HFC RF amplifiers. b. CTB in the overlay as above c. CSO in the overlay as above 7. Group delay – multiple areas where this will come into play depending on design criteria and actual network implementation. 8. Ingress from non-authorized and authorized sources for forward plant and forward plant as a return plant in the TDD environment a. Impact by micro reflection, passive network performance as a result of residential subscribers actions 9. RF requirements for EPoC a. Transmission levels for acceptable operations and co-existence of residential scribers b. Receive level requirements c. Filtering and protection requirement to protect co-existent services 10. Added requirements may make node change outs a requirement because of increased filtering needs to protect the internal fiber components Hybrid of the above 2 examples: This is where the optics may be on separate fibers or wavelengths and combined at and in an existing fiber node. This would increase the performance in the optical segment for the EPoC system but would then have to be combined with the existing channel load whereby the improved optical performance for EPoC may take an added hit in the RF portion of the network. This deals with all of the above in both models and may introduce other elements for a converged network not fully understood. This was the outline I devised for myself which I was going to expand on for the group. Should I send this “as is” for talking points? Tom From: Garavaglia, Andrea [mailto:andreag@xxxxxxxxxxxx] Resending as seems did not went through. Thanks, Andrea From: Garavaglia, Andrea Hi Jorge, all, Please find attach few slides to report our progress on the EPoC performance model, for tomorrow’s call. We like to briefly touch on what we have been doing (5 min. status update) and discuss in larger group the questions listed on slide 6. Thanks, Andrea – on behalf of the team -----Original Appointment----- When: Occurs every Monday from 10:00 AM to 12:00 PM effective 7/23/2012. (UTC-05:00) Eastern Time (US & Canada) NA Dial-In: 1 (866) 427-3611 International: +1-702-599-4015 Passcode: 833773 Screen Sharing: http://training.comcast.net/comcast833773 ________________________________ |