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How to Increase VDSL Upstream Power Level

We've got a customer with an 887VA who is on VDSL2 and is experiencing very poor upstream sync rates.  Downstream sync rate is good.

Looking at the modem stats the upstream power level looks really low, only 3dBm.

Are there some commands I can insert under the controller configuration to force the power level higher?  We used to be able to do this on the 877's with ADSL.

(config-controller)#?

Controller configuration commands:

  bitswap      Bit swap

  default      Set a command to its defaults

  description  Controller specific description

  diagnostics  Diagnostics DELT

  exit         Exit from controller configuration mode

  firmware     Active firmware file name

  help         Description of the interactive help system

  modem        vdsl modem configuration

  no           Negate a command or set its defaults

  operating    Configure auto or specific VDSL operating mode

  shutdown     Shutdown vdsl controller

  sra          Seemless Rate Adaption

  sync         xDSL sync preferences

  training     Dsl firmware training log

Here are the line stats:

Attainable Rate:          18272 kbits/s                     560 kbits/s

Actual Power:                     12.7 dBm                      3.3 dBm

Per Band Status:                 D1           D2           D3           U0           U1           U2           U3

Line Attenuation(dB):   24.2          74.6          N/A          N/A          59.8          N/A          N/A

Signal Attenuation(dB): 24.2          74.6          N/A          N/A          57.2          N/A          N/A

Noise Margin(dB):       12.4          0.0          N/A          N/A          11.9          N/A          N/A

  • WAN Routing and Switching
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New Member

We have similar numbers on a

We have similar numbers on a 2911 router with an ehwic-va-dsl-a:

Attainable Rate:        14600 kbits/s            462 kbits/s
Actual Power:             9.2 dBm                 5.9 dBm
Per Band Status:        D1      D2      D3      U0      U1      U2      U3
Line Attenuation(dB):   27.7    89.4    102.3   8.9     68.6    64.7    N/A
Signal Attenuation(dB): 27.7    N/A     N/A     8.9     0.0     0.0     N/A
Noise Margin(dB):       6.3     N/A     N/A     5.4     N/A     N/A     N/A

 

We figured it was just line conditions, we're about 1000m from the street cabinet but still think upstream could do better.

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