ADC MM702G, Руководство пользователя

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120 MM701G and MM702G User Manual
Standard Annex
Type 2 then select one of the following Annexes:
•
1 — Annex-A for operating conditions typically found in the North American
implementation of G.shdsl
•
2 — Annex-B for operating conditions typically found in the European
implementation of G.shdsl. This is the default mode for the MM701G modem.
•
3 — Auto for automatically negotiating the Annex A or B standard by which this
modem, and the device to which this modem is attached, can operate. This is the
default mode for the MM702G modem.
•
4 — Annex-B_ANFP for operating conditions that include the Annex B standard with
Access Network Frequency Plan Pulse Spectral Density (PSD) mask.
•
5 — Auto_ANFP for automatically negotiating the Annex A or B standard with
Access Network Frequency Plan Pulse Spectral Density (PSD) mask.
Startup Margin
Type 3 then select a number from 1 to 21 for possible values between -10dB through
10dB , or select 22 to completely Disable the margin.The target signal-to-noise margin,
in decibels, that the modem must achieve with a BER of 10
-7
or better to successfully
complete synchronization. The default margin value is 6 dB. A lower margin may
result in a higher data rate, but it can increase noise on the line.
Bit Rate Mode
Type 4 then select either 1 for Adaptive or 2 for Fixed mode. Bit rate mode indicates how
the modem synchronizes with the device to which it is attached. The default for the
MM702G modem is
Fixed mode. The default for the MM701G modem is Adaptive
mode. The following provides more description for each mode.
•
Fixed mode indicates that the modem will synchronize with the other end (a
DSLAM or another modem) at a fixed bit rate through negotiation. The modem
will synchronize at the best rate, up to the data rate specified (page 122), that can
be achieved by both ends.
•
Adaptive mode indicates that prior to modem negotiating a rate, the modem
performs an adaptation phase during which it determines a best possible rate based
on conditions of the line. After adaptive mode, the modem will then negotiate the
best rate that can be achieved with the other end, based on the adaptation results.
3 Type 5 to Apply new configuration for the G.shdsl settings.