Huawei MA5833-BS60 Commissioning Manual page 24

MA5833-BS60
Hardware Commissioning Guide
Run the cable rf-power frameid downstream command to set the adjustment mode to
manual, and configure values of ATT1–ATT3 and EQ1–EQ2. The following table describes
the parameters.
Parameter
adjust-mode adjust-mode
docsis--attenuation docsis-attenuation
catv-attenuation catv-attenuation
main-att main-att
main-first-eq main-first-eq
main-second-eq main-second-eq
In the upstream direction
To ensure the normal operation of the amplifier in the upstream direction, you can plan the
input power of the RF port and adjust the attenuation based on the noise power ratio (NPR)
curve.
Formulas of calculating the attenuation
l
l
Issue 01 (2018-12-12)
NOTE
When configuring a total EQ, you are advised to configure EQ1 before configuring EQ2. For example, if
the total EQ is 18 dB, EQ1 is generally set to 8 dB, and EQ2 is set to 10 dB.
ATT4 (or ATT5) = Input power of the RF port – Rx power of the DOCSIS module +
Gain from the RF port to US
ATT6 (or ATT7) + ATT4 (or ATT5) = Optimum input power of the RF port on a single
channel – Tx optimum receive power on a single channel + Gain from the RF port to
Tx
NOTE
l Input power of the RF port:
l
If a reverse amplifier is installed on a line: Input power of the RF port = Output value of the
reverse amplifier – Attenuation from the reverse amplifier to the RF port of the MA5833-BS60
l If no reverse amplifier is installed on a line: Input power of the RF port = Tx power of the CM
– Attenuation from the CM to the RF port of the MA5833-BS60
l In general, the Rx power of the DOCSIS module is 6 dBmV.
l Gain from the RF port to the US = –6 dB; ATT4 (or ATT5) = 0
l Obtain the optimum input power of the RF port on a single channel based on the NPR curve of Tx
link signals. In the above formula, Optimum input power of the RF port on a single channel =
Optimum input power of Tx link signals – 10 x lg (number of upstream channels) + ATT4 (or ATT5)
Copyright © Huawei Technologies Co., Ltd.
6 Configuring Intelligent RF Adjustment
Adjustment Item
Set it to manual for manual adjustment.
ATT1
ATT2
ATT3
EQ1. Value range: 0.0–8.0
Unit: dB
Default value: 8.0
EQ2. Value range: 0.0–14.0
Unit: dB
Default value: 10.0
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