ADC PG-Flex FRL-842, Руководство пользователя

Страница: 16 / 152

SCP-FRL842-013-01H April 22, 2003
4 ADC Telecommunications, Inc.
HDSL T
RANSMISSION
The system uses HDSL 2B1Q technology to transport 24 DS0s plus signaling over two copper pairs. The HDSL
circuits can be used without repeaters or loop conditioning. Adaptive equalization, scrambling, and a four-level
2B1Q line coding scheme are used to maximize distance and minimize crosstalk.
Table 1 shows the maximum distance between the COT and RT for various wire gauges with or without doublers in
the circuit. These distances are shown for a cable temperature of 68º F (20º C). As the temperature of the cable
increases, the distance decreases.
Table 1. HDSL Distances
Wire Gauge
HDSL Distance (6 dB Margin / 35 dB Loss / 68º F)
Analog Drop
(530
Ω
) No Doubler 1 Doubler 2 Doublers
26 AWG
0.4 mm
9.0 kft
2.8 km
18.0 kft
5.6 km
27.0 kft
8.4 km
6.3 kft
1.9 km
24 AWG
0.5 mm
12.3 kft
3.8 km
24.6 kft
7.6 km
36.9 kft
11.4 km
10.2 kft
3.1 km
22 AWG
0.6 mm
16.1 kft
5.0 km
32.2 kft
10.0 km
48.3 kft
15.0 km
16.3 kft
5.0 km
19 AWG
0.9 mm
22.8 kft
7.0 km
45.6 kft
14.0 km
67.4 kft
21.0 km
32.9 kft
10.0 km
When the RT is powered from the COT, two auxiliary power pairs are required between the COT and RT
for each doubler installed in the HDSL circuit. Refer to the COT Shelf or RT Enclosure technical practice
for additional information on the power pairs.