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3. Configuration
3-20
NOTE:
The range of allowed speeds based on spectrum management
requirements as defined in either ANSI T1.417 or BT Access Network
Spectrum standards are calculated and displayed on the DSL Port
Configuration screen. If Spectrum Management is set to Disable on the
Spectrum Management screen (menu selection A-A-G) (see
Spectrum Management (Models 8355 and 8385)
Allowed Speeds field will display all applicable speeds based on the
Region Setting selected on the Specrum Management screen and the
PSD Mask selection on the DSL Port Configuration screen.
For . . .
Enter . . .
PSD Mask
The type of Power Spectral Density (PSD) mask used as
specified in G.992.1, Annex A or Annex B
(Default = Symmetric).
In Asymmetric mode, the transmit power of the CO unit is
set to 16.8 ± 0.5 dBm and the transmit power of the CPE is
set to 16.5 ± 0.5 dBm when in data mode. In Symmetric
mode, the transmit power of the CO and CPE units are set
to 13.5 dBm when in data mode. So, for longer reach the
transmit power of the CO and CPE units are increased to
help with crosstalk issues. Due to this increase in power,
the power levels between the CO and CPE units are
asymmetric.
Asymmetric – The asymmetric PSD mask is used. Select
Asymmetric when the remote unit transmit power level (is
higher than the CO transmit power level. This selection is
not available if Country Code is set to UK on the Spectrum
Management screen (menu selection A-A-G).
Symmetric – The symmetric PSD mask is used. Select
Symmetric when the remote unit transmit power level is set
to the same value as the CO transmit power level.
EWL (Estimated
The estimated length of the line in kilofeet, or NoLoad for
Working Length)
no load loops. This value is usually specified by the carrier.
This option is available only if Spectrum Management is set
to Enable and Region is set to Annex A on the Spectrum
Management screen (menu selection A-A-G).
EWL = L26 + 3(L24)/4, where L26 is the total length of the
26-gauge cable in the loop excluding any bridged tap and
L24 is the total length of 19, 22, or 24-gauge cable in the
loop excluding any bridged tap.
NOTE: The EWL may have more than one range, for
example, EWL = 8.5 kft – (range 2056 kbps to 832 kbps) in
64 kbps increments.
February 2003
Setting
on page 3-4), then the
8335-A2-GB20-70
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