Crocus SHDSL G703.pdf - FTP Directory Listing

8 Crocus SHDSL G703 Chapter 1
User manual
Introducing the Crocus SHDSL G703
1.4 Power back-off
The Crocus SHDSL G703 features power back-off. Power back-off is a part of the ITU-T G.991.2 SHDSL
recommendation. It reduces the maximum transmit power level if the line conditions are sufficiently good
to operate at a lower transmit level.
Power back-off is performed by default (no configuration attribute). During the ITU-T G.994.1 handshake,
the two sides of the line mutually agree on the transmit level. The transmit level is lowered
between 0 and 6 dB in steps of 1dB.
Important remark
When 2 devices are connected point to point using the lowest speeds, an attenuation is always needed
to get into data state, despite the power back-off mechanism. Connecting the devices with a cable of 1
meter for instance will not work.
For the lowest speeds, a minimum distance of 2 kilometers (simulated or not) is required between the
devices.