ZyXEL Communications IES-1248-71, Руководство пользователя

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Chapter 41 Diagnostic
IES-1248-71/73 User’s Guide
269
41.4 ToneDiag Parameters
The following table lists the tone diagnostic parameters that display, see the ITU-T’s G.992.3
for more information.
farEndActatp:
This is the upstream and downstream Far End Actual Aggregate Transmit
Power (in 0.1 dBm)
i
This is the index number of the DMT sub-carrier.
li.rl
The channel characteristics function is represented in linear format by a scale
factor and a complex number. This is the real part of the complex number used
in producing the channel characteristics function for this sub-carrier.
li.im
The channel characteristics function is represented in linear format by a scale
factor and a complex number. This is the imaginary part of the complex number
used in producing the channel characteristics function for this sub-carrier
log
This is a format for providing channel characteristics. It provides magnitude
values in a logarithmic scale. This can be used in analyzing the physical
condition of the ADSL line.
QLN
The Quiet Line Noise for a DMT sub-carrier is the rms (root mean square) level
of the noise present on the line, when no ADSL signals are present. It is
measured in dBm/Hz. The QLN can be used in analyzing crosstalk.
SNR
This is the upstream and downstream Signal-to-Noise Ratio (in 0.1 dBm). A
DMT sub-carrier’s SNR is the ratio between the received signal power and the
received noise power. The SNR can be used in analyzing time dependent
changes in crosstalk levels and line attenuation (such as those caused by
temperature variations and moisture).
Table 88 LDM Test Parameters (continued)
LABEL DESCRIPTION
Table 89 ToneDiag Parameters
LABEL DESCRIPTION
number_of_
subcarries
Discrete Multi-Tone (DMT) modulation divides up a line’s bandwidth into sub-
carriers (sub-channels) of 4.3125 KHz each.
This number indicates how many upstream and downstream DMT sub-carriers
the ADSL connection is using.
hlinScale:
The channel characteristics function is represented in linear format by a scale
factor and a complex number. This is the maximum upstream and downstream
scale factor used in producing the channel characteristics function.
latn:
This is the upstream and downstream Line Attenuation (in dB).
satn:
This is the upstream and downstream Signal Attenuation (in dB).
snrm:
This is the upstream and downstream Signal-to-Noise Ratio Margin (in dB). A
DMT sub-carrier’s SNR is the ratio between the received signal power and the
received noise power. The signal-to-noise ratio margin is the maximum that the
received noise power could increase with the IES-1248 still being able to meet
its transmission targets.
attndr:
This is the upstream and downstream Attainable Net Data Rate (in bit/s).
farEndActatp:
This is the upstream and downstream Far End Actual Aggregate Transmit
Power (in dBm)
i
This is the index number of the DMT sub-carrier.