Chapter 9: Upstream Cable Access Modules (UCAMs)
STANDARD Revision 1.0
C4® CMTS Release 8.3 User Guide
© 2016 ARRIS Enterprises LLC. All Rights Reserved.
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you choose a number that is already in use, then the existing modulation profile will be overwritten by the new one. There
is almost no limit to the number you can create.
Each user-defined modulation profile is defined by a channel type, such as tdma, and a modulation type, such as 16QAM.
The user-defined profile defines most of the parameters for that modulation and channel type. For example, if you want to
use the user-defined profile for TDMA and 16QAM to create modulation profile 20, enter the following command:
configure cable modulation-profile 20 tdma qam-16
Modulation profile 20 as defined by the above command:
Interval Chan Mod Pre Dif FEC FEC Scr Max Guar L Scr ---Atdma--- Prea -----Scdma-----
Usage Type Type Len Enc CW amb Bur Time C amb Int Int mble TCM Int Sp Sub
Code En Len Seed Siz Size S En Depth Block Type En Size En Cod
---------------------------------------------------------------------------------------------
1 request tdma qpsk 56 F 0 16 338 0 8 F T - - - - - - -
3 initial tdma qpsk 640 F 5 34 338 0 48 F T - - - - - - -
4 station tdma qpsk 384 F 5 34 338 0 48 F T - - - - - - -
5 short tdma q16 168 F 6 78 338 23 8 T T - - - - - - -
6 long tdma q16 192 F 8 220 338 0 8 T T - - - - - - -
Basically, user-defined modulation profiles allow the user to specify the channel type and the modulation rate for the data
IUCs and the rest of the information for the modulation profile is filled in with recommended values. These recommended
values are generic values that should work across a wide variety of plants. Users may want to optimize these values to the
specific needs of their cable plant.
The following channel types are currently supported:
atdma
- Use preconfigured ATDMA modulation profile
scdma
- Use preconfigured SCDMA modulation profile
tdma
- Use preconfigured 12U CAM TDMA modulation profile
tdma-atdma
- Use preconfigured TDMA-ATDMA modulation profile
These user-defined modulation profiles are controlled by the CMTS software. These modulation profiles may evolve and
change slightly with different software versions.
configure cable modulation-profile 100 ?
atdma - Use preconfigured ATDMA modulation profile
iuc - IUC type
scdma - Use preconfigured SCDMA modulation profile
tdma - Use preconfigured CAM TDMA modulation profile
tdma-atdma - Use preconfigured TDMA-ATDMA modulation profile
configure cable modulation-profile 100 atdma ?