SAGEM 3P@C
DS indicates Downstream
1.1.1.58Related Parameters of ADSL Voice Splitter
The copper wire bears the original voice signals and the new ADSL signals, because the voice signal takes the form of
~1.1MHz.To prevent the high frequency signals from impacting on the voice signals and to ensure the quality of communication, the front end of the PSTN switch and the line of the subscriber line end are added with the voice splitter. The voice splitter is in fact a Low Pass Filter (LPF), which only permits the voice signals to pass and blocks the high frequency ADSL signals. The ADSL voice splitter has the following
Figure
The voice splitter uses the passive devices, connected on the line in series, so it has a high reliability, but with the time elapse, it will also be of aged deterioration, mainly reflecting in the following respects:
The increase of the DC loop resistance affects the connection rate of the ADSL line.
Aging of capacitance affects the communication quality and the ADSL service.
The reference values of the main parameters of the voice splitter is shown in the table below:
Table
Test item | Condition | Reference index | |
|
| ||
DC resistance (Ω) | Line A and B | = 25Ω | |
|
| Open DC resistance = 5MΩ | |
Reflection | |||
18dB | |||
attenuation (dB) | |||
> | |||
| |||
Longitudinal | 58 dB | ||
balance (dB) | 53 dB |
1.1.1.59Conditions for ADSL central office end setting
The Central office terminal of ADSL is the equipment featured by easy management and operation, it can meet the demands for different service types through the setting of some
3P@C Installation Manual
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