Quote:
Originally Posted by vm_tech
I know of an area that will be going to 6 upstream frequencies in the very near future. That's 6 individual not aware of how the bonding is going to be just yet, but I imagine it's with one eye on 4x bonding. A few of the nodes need the transmitters changing as they struggle with the 6 carriers.
|
There are a bunch with 3 or 4 DOCSIS 2.0 carriers already. The problem is that when you go from 2 to 3 or 4 bonded channels you lose 3dB of maximum transmit power. You've doubled the range of the power so it's spread across a wider band.
Any modems that are transmitting at over 51dB right now will max out if they're taken to 3 or 4 bonded channels.
This might be remedied by a feature called extended upstream transmit power which puts the maximum back at 54, however that comes with the price of higher load on the upstream lasers and risks clipping.
As far as I know they're going to try it in a few areas with DFB transmitters and see how it goes. Remaining nodes with F-P transmitters are going to have the transmitters replaced with DFBs if they're field replaceable else the whole thing will have to come out.