ADC MM702G, User Manual

Page: 67 / 168

Chapter 6: Configuring DSL Parameters
MM701G and MM702G User Manual 59
•
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.
•
Annex-B_ANFP for operating conditions that include the Annex B standard with
Access Network Frequency Plan Pulse Spectral Density (PSD) mask.
•
Auto_ANFP for automatically negotiating the Annex A or B standard with Access
Network Frequency Plan Pulse Spectral Density (PSD) mask.
Startup 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. Possible values are
-10dB
through
10dB
, or to completely
Disable
the
margin.
Bit Rate Mode
Bit rate mode indicates how the modem synchronizes with the device to which it is
attached in either a
Fixed or Adaptive mode. The default for the MM702G modem is
Fixed mode. The default for the MM701G modem is Adaptive 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 61 ), 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 Click Apply .