System information

FCD 901 48
Issue R2A, 07.2009
XMP1 Release 5.5 System Description
SDSL in XMP1
Aastra Proprietary Information Page 5-1
Chapter 5
SDSL in XMP1
5.1 General
SDSL (international designation: SHDSL) is a further development of the
HDSL technology introduced some years ago. The SDSL TC-PAM16 line
code standardized by both ETSI and ITU permits nearly the same
transmission range on one copper pair as HDSL on two pairs. With two pairs
and high-quality cables, SDSL can span longer distances than HDSL.
Advantages of SDSL:
• Good spectral compatibility with other services in the same cable;
• Management of up to 8 repeaters (1 pair or 2 pairs) on one line section;
• Improved jitter/Wander behavior for series switching of line sections;
• Transmission of sub-bit rates (nx64, n=3...32) for a further increase in
the transmission range.
In case of short line sections, the implemented power backoff function
automatically reduces the transmit power to a value ensuring that
interferences affecting neighboring services can be kept as low as possible.