Alcatel Speed Touch 591s, Technical User'S Manual

Page: 52 / 184

4 — Configuring generic node parameters
4-8 Speed Touch 591s Technical Practices
90-8785-01 February 2001
4.2 Configuring the network port
Since the Speed Touch 591s is a slave to the CO device at the other end of the
SHDSL line, the majority of network port parameters are configured by the CO
device.
The CO device can configure, enable, or disable the following parameters on the
network port on the Speed Touch 591s:
•
SHDSL line rate (192, 384, 512, 768, 1024, 1152, 1536, 2048, or 2304 kb/s)
•
signal-to-noise margin threshold
•
power backoff
•
loopbacks
•
PSD mask used on the SHDSL line (European or North American, symmetric or
asymmetric)
The only network port parameter that can be configured locally on the Speed Touch
591s NMTI is power backoff.
Power backoff
The power backoff feature automatically reduces the power transmitted by the
network port over the SHDSL line. During the line training phase, the transmitted
power is compared with the strength of the signal received at the other end of the line.
If possible, transmit power is then reduced to a level that is sufficient for the signal
to be correctly received at the other end of the line while still maintaining a maximum
BER of 10
-7
.
On short or relatively loss-free lines, this feature reduces the risk of crosstalk being
generated on neighboring lines by unnecessarily strong signals when a lower signal
strength would still produce a clean signal at the receiver.
Procedure 4-12 Configuring power backoff
CONFIG — OBJECT — PORT — <N>
↵
— LINE_CFG — ENABLE_PBO/DISABLE_PBO
Note —
Power backoff configurations contained in EOC requests
from CO devices at the other end of the SHDSL line override any
local NMTI power backoff configurations on the Speed Touch 591s.