Nortel Networks 1000 - Manual (Page 142)

142 NT1R20 Off-Premise Station Analog Line card
These factors must be considered when planning applications using the
OPS analog line card. They are important when considering configurations
other than the traditional OPS application as shown in
Figure 90
"NTCK80AA/AB/AC/AD" (page 332) . The following provides basic
transmission planning guidelines for various OPS applications.
Port-to-port loss
Loss is inserted between OPS analog line card ports and other ports in
accordance with the loss plan. This plan determines the port-to-port loss
for each call.
When a port is configured for CLS OPS, loss is programmed into the
OPS analog line card on a call-by-call basis. When configured for CLS
ONS, an OPS analog line card port is programmed to a value that is fixed
for all calls. The loss in the other port involved in the call can vary on a
call-by-call basis to achieve the total loss scheduled by the plan.
For satisfactory transmission performance, particularly on connections
between the public network and an OPS termination, it is recommended
that facilities conform to the following:
•
Total 1 kHz loss from the local serving CO to the OPS terminal should
not exceed 7.0 dB. The total loss in the facility between the PBX and
the terminal must not exceed 4.5 dB. See
Figure 24 "Traditional OPS
application configuration" (page 138) .
The following requirements are based on historic Inserted Connection
Loss (ICL) objectives:
— PBX – CO trunk: 5 dB with gain; 0 – 4.0 dB without gain
— OPS line: 4.0 dB with gain; 0 – 4.5 dB without gain. In recent times
economic and technological considerations led to modifications
of these historic objectives. But since the loss provisions in the
PBX for OPS are constrained by regulatory requirements as well
as industry standards, they are not designed to compensate for
modified ICL designs in the connecting facilities.
•
Nortel recommends that the attenuation distortion (frequency response)
of the OPS facility be within ±3.0 dB over the frequency range from
300 to 3000 Hz. It is desirable that this bandwidth extend from 200 to
3200 Hz.
• The terminating impedance of the facility at the OPS port be
approximately that of 600 ohms cable.
If the OPS line facility loss is greater than 4.5 dB but does not exceed 15
dB, line treatment using a switched-gain Voice Frequency Repeater (VFR)
extends the voice range.
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 02.06 Standard
27 August 2008
Copyright © 2003-2008 Nortel Networks
.