Appendix; Rf Specifications - Cisco UBR7225VXR Hardware Installation Manual

RF Specifications

Information in the following tables is from the DOCSIS and EuroDOCSIS Radio Frequency Interface
Specification, and should be considered minimum recommended performance criteria for reliable data
transmission on cable networks. The full specification may be found at the CableLabs website
(http://www.cablemodem.com), and additional Euro-DOCSIS information may be found at ComLabs
website (http://www.tcomlabs.com).
• NCTA—"NCTA Recommended Practices for Measurements on Cable Television Systems, 2nd
Edition"- National Cable Television Association, Washington DC, revised October 1993
• CableLabs1—"Two-Way Cable Television System Characterization," Cable Television
Laboratories, Inc., April 12, 1995
CableLabs2—"Digital Transmission Characterization of Cable Television Systems," Cable
•
Television Laboratories, Inc., November, 1999
Raw data rate in Table B-1 and Table B-2 includes nominal data throughput plus overhead.
Note
Table B-1
Modulation Format
QAM-64
QAM-256
QAM-64
QAM-256
Table B-2
Symbol Rate,
ksym/sec
160
320
640
OL-17309-01
Downstream Channel Data Rates
Channel Symbol Rate,
Bandwidth, MHz Msym/sec
6 5.056941
6 5.360537
8 6.952
8 6.952
Upstream Channel Data Rates
Channel QPSK Raw
Bandwidth, Data Rate,
MHz Mbps
0.20 0.32
0.40 0.64
0.80 1.28
Cisco uBR7225VXR Universal Broadband Router Hardware Installation Guide
A P P E N D I X
Raw Data Rate,
Mbps
30.34
42.88
41.71
55.62
QPSK Nominal QAM-16 Raw
Data Rate, Data Rate,
Mbps Mbps
~0.3 0.64
~0.6 1.28
~1.2 2.56
B
Nominal Data
Rate, Mbps
~27
~38
~37
~50
QAM-16
Nominal Data
Rate, Mbps
~0.6
~1.2
~2.3
B-1