User's Manual

illustrates a four-sector system that utilizes the ABAB frequency pattern and one downstream
logical channel, which is split ultimately to all four sectors. This system has an aggregate raw
downstream capacity of 10 Mbps, when utilizing QPSK modulation, and 20 Mbps when using
16-QAM modulation.
W-CMTS
Downstream 1
Upconverter freq-A
Upconverter freq-B
2-way splitter
Trans/Ant 1
Trans/Ant 3
2-way splitter
Trans/Ant 2
Trans/Ant 4
2-way splitter
Figure 4-3: Four-Sector ABAB System with 1 downstream data stream, total 10 Mbps.
Figure 4-4, below, illustrates a four-sector system that utilizes the ABAB frequency pattern and
two
downstream logical channels that are split ultimately to all four sectors. This system has an
aggregate raw downstream capacity of 20 Mbps, when utilizing QPSK modulation, and 40 Mbps
when using 16-QAM modulation.
June 2003 Page 4-5