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Cisco uBR7100 Series and Cisco uBR7100E Series Universal Broadband Router Hardware Installation Guide
OL-5916-01
Appendix A System Specifications
RF Specifications
RF Specifications
DOCSIS Upstream and Downstream Specifications
The recommended settings listed in the following tables are based on a hybrid fiber-coaxial cable (HFC)
network in which the digital signal is carried 10 dB below the adjacent analog video channel. If the
digital signal on your network is carried 6 dB below the adjacent analog video channel, add 4 dB to the
recommended settings in Table A-5 and Table A-6.
Table A-3 Typical RF Upstream Bandwidth and Modulation
Upstream Bandwidth QPSK Data Throughput 16 QAM Data Throughput
200 kHz 0.3 Mbs 0.6 Mbs
400 kHz 0.6 Mbs 1.2 Mbs
800 kHz 1.2 Mbs 2.3 Mbs
1600 kHz 2.3 Mbs 4.5 Mbs
3200 kHz 4.6 Mbs 9.0 Mbs
Table A-4 Typical RF Downstream Modulation
Downstream Bandwidth 64 QAM Data Throughput 256 QAM Data Throughput
6 MHz 27.0 Mbs 38.0 Mbs
8 MHz 38.0 Mbs 56.0 Mbs
Table A-5 DOCSIS Cable Upstream RF Specifications
Specification DOCSIS Specifications
1
Minimum Settings
2
Your Headend Settings
System/Channel
Frequency range 5 to 42 MHz 5 to 42 MHz
Transit delay, CMTS to furthest
customer
< 0.800 µsec < 0.800 µsec
Carrier to noise ratio > 25 dB (QPSK
3
)
4
> 25 dB (16 QAM
5
)
4
> 21 dB (QPSK)
4
> 24 dB (16 QAM)
4
Carrier to ingress power ratio > 25 dB > 25 dB
Carrier to interference ratio > 25 dB (QPSK)
4
> 25 dB (16 QAM)
4
> 21 dB (QPSK)
4
> 24 dB (16 QAM)
4
Carrier hum modulation < –23 dBc
6
(7%) < –23 dBc (7%)
Burst noise < 10 µsec < 10 µsec
Amplitude ripple 0.5 dB/MHz 0.5 dB/MHz
Group delay ripple 200 ns/MHz 200 ns/MHz
Micro reflections (single echo) –10 dBc @ < 0.5 µsec
–20 dBc @ < 1.0 µsec
–10 dBc @ < 0.5 µsec
–20 dBc @ < 1.0 µsec