ZyXEL Communications IES-1248-51 Podręcznik Użytkownika Pobierz pdf (Strona 499)

100

101

Chapter 64 ADSL Commands

IES-1248-51V User’s Guide

499

The following table lists the line diagnostics test parameters that display, see the

ITU-T’s G.992.3 for more information.

Table 190 Line Diagnostics Get 992.3 Command

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.

The first number is the total number of DMT sub-carriers the ADSL

connection is using. The second number indicates how many

upstream 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. These are the maximum

upstream and downstream scale factors 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-1248-51V 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).

1 2 ... 494 495 496 497 498 499 500 501 502 503 504 ... 653 654

Komentarze do niniejszej Instrukcji

Brak uwag

ZyXEL Communications IES-1248-51 Podręcznik Użytkownika Strona 499

Komentarze do niniejszej Instrukcji

Powiązane produkty i podręczniki dla Networking ZyXEL Communications IES-1248-51