ZyXEL Communications IES-2000, Руководство пользователя

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IES-2000/3000 User’s Guide
27-6 VDSL-Related Commands
Table 27-5 VDSL Channel Status Counters
FIELD DESCRIPTION
RSTSTAT Reset Status indicates the reason for the most recent system reset.
FAILCNT This field displays VDSL Fail counter information.
DS and US The following parameters apply to both upstream and downstream VDSL.
QAM Constellation shows the modulation method and speed. The constellations are QAM
4, QAM 8, QAM 16, QAM 64, QAM 256 where QAM (Quadrature Amplitude
Modulation) defines how many bits there are per symbol; for example QAM 4 means 2
bits per symbol (2
2
), QAM 8, 3 bits (2
3
) per symbol and so on.
Int Int (Interpolation) defines how fast the symbols go through the line. It is equal to
25.0MHz / baud rate, so for example, Int 8 = 25.0 / 8 Mbaud.
Rate This is the VDSL raw speed.
Fc This is the carrier frequency
SNR The higher the SNR (Signal-to-Noise Ratio) number, the better. SNR (Signal-to-Noise
Ratio is the ratio of the amplitude of the desired signal to the amplitude of noise
signals at a given point in time).
MSE This is the Minimum Square Error. The minimum mean-square error (also known as
MMSE) performance measure is a popular metric for optimal signal processing.
RS_ERR This is the count of bit errors detected and corrected by Reed-Solomon code. Reed-
Solomon codes are block-based error correcting codes and are used to correct errors
in many systems.
Power Parameters:
MIN_PSD This is the mimimum Power Spectrum Density (power divided by bandwidth).
MAX_PSD This is the maximum Power Spectrum Density (power divided by bandwidth).
TXPWR This field displays transmission power information in hexadecimal format.
POCO Port Output Control registers provide the control bit information.
PSD This is the Power Spectrum Density (power divided by bandwidth).
27.2.7 VDSL Patch Command
Syntax:
vdsl patch [lt|nt]
This command makes the VLC1012 load new VDSL modem code into the VLC1012 (LT) or VDSL subscriber
modem (NT). If
lt
is specified, the VLC1012 will load the VDSL modem code into the VLC1012. If
nt
is
specified, the VLC1012 will load the VDSL modem code into the VDSL subscriber modem (P841). The VDSL
connection should automatically reconnect after the new VDSL modem code has been successfully loaded.