Maintenance strategy
Signaling
Maintenance Procedures
41
December 2003
Table 16, Quantization distortion loss,
on page 41 lists the quantization distortion loss in the system for
analog port-to-digital port and digital port-to-analog port.
Impulse noise
On 95% or more of all connections, the impulse noise is 0 count (hits) in 5 minutes at +55 dBrnC
(decibels above reference noise with C-filter) during the busy hour.
ERL and SFRL talking state
Echo-Return Loss (ERL) and Single-Frequency Return Loss (SFRL) performance are usually dominated
by termination and/or loop input impedances. The system provides an acceptable level of echo
performance if the ERL and SFRL are met, as follows:
Table 15: Quantization distortion loss (analog port-to-analog port)
Signal level
Distortion loss
0 to -30 dBm0
>33 dB
-40 dBm0
>27 dB
-45 dBm0
>22 dB
Table 16: Quantization distortion loss
1
1 Terminating Impedance: 600 Ohms nominal
Trunk balance impedance (selectable): 600 Ohms
nominal or complex Z [350 Ohms + (1 k Ohms in
parallel with 0.215uF)]
Signal level
Distortion loss
0 to -30 dBm0
>35 dB
-40 dBm0
>29 dB
-45 dBm0
>25 dB
Table 17: ERL and SFRL performances by connection type
Type of connection
ERL and SFRL performance
Station-to-station
ERL should meet or exceed 18 dB
SFRL should meet or exceed 12 dB
Station to 4-wire trunk connection
ERL should meet or exceed 24 dB
SFRL should meet or exceed 14 dB
Station to 2-wire trunk connection
ERL should meet or exceed 18 dB
SFRL should meet or exceed 12 dB
4-wire to 4-wire trunk connection
ERL should meet or exceed 27 dB
SFRL should meet or exceed 20 dB
Summary of Contents for CMC1
Page 1: ...Maintenance Procedures 555 245 103 Issue 1 1 December 2003 ...
Page 14: ...Contents 14 Maintenance Procedures December 2003 ...
Page 416: ...Additional maintenance procedures IP Telephones 416 Maintenance Procedures December 2003 ...
Page 426: ...Index X 426 Maintenance Procedures December 2003 ...
