Arris C4C - Optimizing a Modulation Profile

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. 311
qam-8 - Default ATDMA QAM-8 modulation profile
qam-16 - Default ATDMA QAM-16 modulation profile
qam-32 - Default ATDMA QAM-32 modulation profile
qam-64 - Default ATDMA QAM-64 modulation profile
qpsk - Default ATDMA QPSK modulation profile
configure cable modulation-profile 100 scdma ?
qam-8 - Default SCDMA QAM-8 modulation profile
qam-16 - Default SCDMA QAM-16 modulation profile
qam-32 - Default SCDMA QAM-32 modulation profile
qam-64 - Default SCDMA QAM-64 modulation profile
qpsk - Default SCDMA QPSK modulation profile
configure cable modulation-profile 100 tdma ?
qam-16 - Default TDMA QAM-16 profile
qpsk - Default TDMA QPSK modulation profile
configure cable modulation-profile 100 tdma-atdma ?
qpsk - Default TDMA-ATDMA QPSK modulation profile
qam-8 - Default TDMA - QPSK for data IUCs and ATDMA - QAM8 for data IUCs
qam-16 - Default TDMA - QAM16 for data IUCs and ATDMA - QAM16 for data IUCs
qam-32 - Default TDMA - QAM16 for data IUCs and ATDMA - QAM32 for data IUCs
qam-64 - Default TDMA - QAM16 for data IUCs and ATDMA - QAM64 for data IUCs
Displaying Modulation Profiles
Use the following command to view a modulation profile:
show cable modulation-profile n
Where n = the number of the desired profile.
Optimizing a Modulation Profile
This section is meant to serve as a guide to some of the issues that are involved in optimizing a modulation profile.
Optimizing a modulation profile involves many factors; this document does not claim to explain them all.
What you are really trying to do is to optimize throughput in the upstream channel connected to the CMTS and still
maintain an acceptable packet error rate. This distinction is important because noise on the upstream channel plays a big
role in determining the best modulation profile to use. Additionally, noise on an upstream channel is not consistent over