ADTRAN 1247026L1, Руководство по установке и обслуживанию

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HDSL T200 HTU-R, Span Powered, 60 mA Installation and Maintenance Practice
6 61247026L1-5A
Recommended maximum local loop loss information for PIC cable at 70°F, 135
Ω
resistive
termination is provided in Table 4 .
An approximation for the maximum amount of wideband noise on an HDSL local loop as
measured by a 50 kb filter is
≤
31 dBrn.
An approximation for the maximum level of impulse noise as measured using a 50 kb filter on
an HDSL loop is
≤
50 dBrn.
NOTE
These approximations are to be used as guidelines only and may
vary slightly on different loops. Adhering to the guidelines should
produce performance in excess of 10
-7 BER.
Table 3. HDSL Loss Values
(200 kHz cable loss in dB/kft at 135 Ω )
Cable Gauge Cable Type
Temperature
68° 90° 120°
26 PIC 3.902 4.051 4.253
26 Pulp 4.030 4.179 4.381
24 PIC 2.863 2.957 3.083
24 Pulp 3.159 3.257 3.391
22 PIC 2.198 2.255 2.333
22 Pulp 2.483 2.45 2.629
19 PIC 1.551 1.587 1.634
19 Pulp 1.817 1.856 1.909
Table 4. Loop Insertion Loss Data
Frequency (Hz) Maximum Loss (dB)
3000 12.00
10000 15.00
50000 25.50
100000 30.00
150000 32.75
196000 35.00
200000 32.25
250000 37.50
325000 42.00