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Chapter 54 ADSL Commands

IES-612-51 User’s Guide

347

54.4.10 SELT Diagnostic Set Command Example

The following example starts a SELT test on ADSL port 1.

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-612-51 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.

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. It is measured in dB. 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. The QLN can be used in analyzing crosstalk.

SNR This is the upstream and downstream Signal-to-Noise Ratio (in dB). 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 139 Line Diagnostics Get 992.3 Command (continued)

LABEL DESCRIPTION

Figure 166 SELT Diagnostic Set Command Example

ras> adsl linediag setselt 1

1 2 ... 342 343 344 345 346 347 348 349 350 351 352 ... 413 414

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