Juniper Networks G10 CMTS manual 177, Upstream RF Channel Transmission Characteristics

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	<= 0.800 msec (typically much less)
CM or CMTS
Carrier-to-noise ratio	Not less than 25 dB
Carrier-to-ingress power (the sum of discrete and	Not less than 25 dB2
broadband ingress signals) ratio
Carrier- to-interference (the sum of noise, distortion, common-path	Not less than 25 dB
distortion and cross-modulation) ratio
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 cases3,4,5
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).

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Radio Frequency (RF) Specifications 177