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Table 48, Upstream rf channel transmission characteristics – Juniper Networks G10 CMTS User Manual

Page 193

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Radio Frequency (RF) Specifications

177

Radio Frequency (RF) Specifications

Table 48: Upstream RF Channel Transmission Characteristics

Parameter

Value

Frequency range

5 to 42 MHz edge to edge

Transit delay from the most distant CM to the nearest

CM or CMTS

<= 0.800 msec (typically much less)

Carrier-to-noise ratio

Not less than 25 dB

Carrier-to-ingress power (the sum of discrete and

broadband ingress signals) ratio

Not less than 25 dB

2

Carrier- to-interference (the sum of noise, distortion, common-path
distortion and cross-modulation) ratio

Not less than 25 dB

Carrier hum modulation

Not greater than -23 dBc (7.0%)

Burst noise

Not longer than 10 msec at a 1 kHz average rate for most cases

3,4,5

Amplitude ripple

5-42 MHz: 0.5 dB/MHz

Group delay ripple

5-42 MHz: 200 ns/MHz

Micro-reflections -- single echo

-10 dBc @ <= 0.5 m sec
-20 dBc @ <= 1.0 m sec
-30 dBc @ > 1.0 m sec

Seasonal and diurnal signal level variation

Not greater than 8 dB min to max

1. Transmission is from the CM output at the customer location to the headend.
2. Ingress avoidance or tolerance techniques MAY be used to ensure operation in the presence of time-varying discrete ingress signals that

could be as high as 0 dBc [CableLabs1].

3. Amplitude and frequency characteristics sufficiently strong to partially or wholly mask the data carrier.
4. CableLabs report containing distribution of return-path burst noise measurements and measurement method is forthcoming.
5. Impulse noise levels more prevalent at lower frequencies (< 15 MHz).