1 256-QAM - SCTE - Alaska
1 256-QAM - SCTE - Alaska
1 256-QAM - SCTE - Alaska
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
DOCSIS Checklist<br />
Headend (downstream) CMTS or upconverter output<br />
Test performed Parameter<br />
Parameter value Measured value/comments<br />
<br />
CMTS downstream IF output +42 dBmV 1<br />
Digitally modulated carrier<br />
amplitude at upconverter<br />
input<br />
Digitally modulated carrier<br />
amplitude at upconverter<br />
output<br />
Digitally modulated carrier<br />
center frequency<br />
Carrier-to-noise ratio<br />
Modulation error ratio<br />
(MER) 3<br />
Pre-FEC BER 4<br />
Post FEC BER 5<br />
Amplitude ripple (in-channel<br />
flatness)<br />
Group delay ripple<br />
Constellation evaluation<br />
+25 to +35 dBmV 2<br />
+50 to +61 dBmV<br />
91-857 MHz<br />
Not less than 35 dB<br />
64-<strong>QAM</strong>: 27 dB minimum<br />
<strong>256</strong>-<strong>QAM</strong>: 31 dB minimum<br />
N/A<br />
Less than or equal to 10 -8<br />
3 dB 6<br />
75 ns maximum<br />
Look for evidence of gain compression;<br />
phase noise; I-Q imbalance; coherent<br />
interference; excessive noise; and<br />
clipping<br />
<strong>256</strong>-<strong>QAM</strong><br />
© 2003, Cisco Systems, Inc. All rights reserved.<br />
30
Change language