RAD Data comm ASMi-52 manual Configuring the Power Spectral Density, Configuring Line Probing

Installation and Operation Manual Chapter 4 Configuration

Configuring the Power Spectral Density

By configuring the power spectral density, you define the amount of power applied to the spectrum of frequencies that carry the information signal in order to achieve a satisfactory level of signal strength at the receiving end of the circuit.

The power spectral density can be configured for the ASMi-52 units with the line probing set to fixed.

The power spectral density value depends on the selected modems’ compatibility: Annex A or Annex B. The possible values are:

•Symmetric, supported in both Annex A and Annex B modes.

•Asymmetric, supported in Annex A at 768 kbps and in Annex B at 2048 kbps.

To configure the power spectral density:

1. From the SHDSL Local Port menu, select Asym PSD (Main menu >

	Configuration > SHDSL Configuration > SHDSL Local Port > Asym PSD) to
	choose the power spectral density value: symmetrical or asymmetrical.
	The display is refreshed and a new value appears.
	2. Select Save to save the changes.
Note
	•
	Remote ASMi-52 units automatically detect the line power density. This parameter
	is permanently set to Sym/Asym Enable and cannot be changed.

Configuring Line Probing

By configuring this parameter, you force ASMi-52 to perform line probing in order to find the best possible rate of transmission – adaptive rate. Or you command the modem to skip the rate adaptation phase – fixed rate.

Only central ASMi-52 units with the 2-wire line interface support fixed and adaptive rates, remote units operate with adaptive rate only.

ASMi-52 units with the 4-wire line interface support only fixed rate.

To configure line probing:

1. From the SHDSL Local Port menu, select Line Prob (Main menu > Configuration > SHDSL Configuration > SHDSL Local Port > Line Prob).

The display is refreshed and a new value appears. 2. Select Save to save the changes.

Setting the Loop Attenuation Threshold

Loop attenuation is different (in dB) between the power transmitted from the ASMi-52 modem and the power received by the unit operating at the other side of the application. By setting the threshold, the modem is instructed to generate minor alarm (LOOP ATTN. OVER LINE A/B) when the selected loop attenuation threshold value is exceeded.

To set the loop attenuation threshold:

1. From the SHDSL Local Port/SHDSL Remote Port/SHDSL Repeater menu, select Loop attenuation threshold (Main menu > Configuration > SHDSL

ASMi-52 Ver. 2.5 Configuring the Physical Ports 4-25